Green Roofs Report 2.07.05 by dandanhuanghuang


									                            Green Roofs
                        Benefits and Cost

                                In association with

Sustainable Eastside is a project supported by:
                         GREEN ROOFS
            Benefits and cost implications

Eastside Sustainability Advisors

Birmingham City Council Eastside 18th Floor The McLaren Building 35 Dale
End Birmingham B4 7LN
                                                   GREEN ROOFS
                                                   Benefits and cost

                 7, Dartmouth Grove
                      SE10 8AR
                  T - 020 8692 2109
                                A Report for
              in association with
                                                        Sustainable Eastside
                    PO Box 13313
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        E -
          W –

                  Dusty Gedge and Mathew Frith
Final – v1
                5 March 2004
                                    Approved by
                                     John Newton
                                                                March 2004

1.0     Introduction ........................................................................... 4

2.0     Green Roofs – Introduction ................................................... 5

3.0     Definitions ............................................................................. 7

4.0     Benefits of Green Roofs ...................................................... 11

5.0     Cost Benefits of Green roofs ............................................... 22

6.0     Costs ................................................................................... 24

7.0     Barriers to Green roofs........................................................ 28

8.0     Policy Framework for Green Roofs ..................................... 31

Case Studies ................................................................................ 38
Green Roofs – Benefits and cost implications
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1.0 Introduction

          Sustainable Eastside commissioned and Ecology
          Consultancy Ltd to undertake a cost benefit analysis of green roofs and
          green/brown roofs, compared to conventional roofing systems.

          This report follows a preliminary report that established the scope of
          research and provided an overview of green roofs. It extends that
          earlier report to provide a comprehensive analysis of green/brown roofs
          in terms of their benefits and cost implications.

          This report provides evidence that green/brown roofs provide the
          potential to improve visual amenity/biodiversity habitats and thermal
          insulation. They can be installed on new buildings and incorporated in
          the conversion and retro fitted on existing structures where appropriate.
          However, there is widespread ignorance of green roof technology with
          the professions involved in urban regeneration and this has lead to
          some misconceptions of the technology. It is widely believed that they
          are expensive [true in some cases] to establish, costly and difficult to
          maintain, and can increase the risk of leakage [the former could not be
          further from the truth as a green roof installed properly actually provides
          added protection to the waterproofing element]. This report aims to
          provide details of both the advantages and disadvantages of green

          Green roofs can vary from roof gardens with access, shrubs and trees,
          to roofs rich in biodiversity, or monocultures of sedums that provide an
          instant green effect at the expense of biodiversity.

          A roof’s primary function, whether it is green or grey, is to provide
          protection from the elements, especially water, to the building it is part
          of. Green roofs have the advantage of providing this, and further
          protection to waterproofing layers, with the added benefits to the
          environment as laid out in this report.

          This report provides

                         •    Definitions of various green roof systems
                         •    Green/Brown roofs – their differences and similarities
                         •    Benefits
                         •    Cost benefits
                         •    Researched costs
                         •    Published costs
                         •    Barriers
                         •    Policy framework
                         •    Case Studies
                         •    Conclusions & Ecology Consultancy Ltd                                               4
Green Roofs – Benefits and cost implications
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2.0 Green Roofs – Introduction

2.1       Overview

          Green roofs are vegetated roof surfaces. They have been around for
          centuries as used on domestic houses in Northern and Western
          Europe. In the late 20th century, innovation in design in Germany and
          concerns over the environmental impacts of buildings in both urban and
          rural locations led to green roofs becoming a legal requirement in
          certain countries and areas of Europe. Germany leads the way and
          now has a green roof industry worth £37 million. 10% of flat roofs in
          Germany are now green. Developers and owners are given incentives
          whereby they are allowed a reduction in business rates as they are
          deemed to be providing a service to the community.

          In Switzerland green roofs are a legal requirement in many cantons
          although the amount of roof space required to be green does vary. In
          the UK there are no such policies at a government level. However,
          there is now a growing interest in their use and the authors of this
          report have been led to believe that there has been a 300% growth in
          approaches to the green roof industry in the last year. Some of this has
          been down to a growing interest in green roofs by conservationists,
          especially in London, in a belief that such systems can help meet
          regional and local biodiversity action plan targets.

          The environmental benefits of green roofs and their long-term benefits
          to building owners are not widely known in the UK. However, they are
          tangible and offer a long-term sustainable solution on a number of
          counts. The problem has been that the majority of green roofs are to be
          found on landmark buildings or environmental centres designed by
          innovative architects and developers. As yet they are not mainstream,
          and the main barrier is perceived to be their initial capital cost.

2.2       Green roofs in the UK and the West Midlands

          Green roofs are appearing throughout the UK for a variety of reasons.
          The largest green roof in the country was recently installed on the new
          Rolls Royce factory in Chichester, West Sussex [40,000m2]. The fact
          that Rolls Royce is now owned by BMW suggests that this roof is partly
          down to the fact that most BMW factories in Germany now have green
          roofs. Large areas of green roofs are already present and planned for
          in London.

          In the West Midlands the authors are aware of a number of green roofs:
          Walsall Bus Garage, Wolverhampton University and Birmingham
          Children’s Hospital. The new Fort Dunlop development in Birmingham
          is to include a green roof within the development brief, in part in
          response to concerns over the conservation of the black redstart, a & Ecology Consultancy Ltd                                            5
Green Roofs – Benefits and cost implications
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          protected bird species. This particular issue has been a key lever in
          London for green roof establishment. Fiveways and Edgbaston
          Shopping Centres are considering green roofs in their renewal
          schemes & Ecology Consultancy Ltd                                         6
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3.0 Definitions

          Green roofs fall in to two general categories: intensive and extensive. In
          between these two generic types there are a number of other green
          roof solutions including semi-intensive and semi-extensive.

3.1      Intensive green roofs

         Intensive green roofs have a deep growing medium, which allows the
         use of trees and shrubs. Some city parks are in fact intensive green
         roofs, such as the parks within the Canary Wharf Estate at Canada
         Square and West Ferry Circus, and the roof of Cannon Street Station in

                                                                                G. Kadas

         The depth of the growing medium places extra loading requirements on
         the building structure and requires a complex irrigation system for
         maintenance. As a result, intensive roofs are generally quite costly and
         require extra structural design to the building.

3.2       Extensive Green Roofs

          Extensive green roofs have a thin growing medium and require minimal
          maintenance, and in general do not require irrigation [some require
          irrigation initially]. They are generally less costly to install than intensive
          green roofs.

          There are 3 types currently used in the UK: & Ecology Consultancy Ltd                                                   7
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          1. Sedum mats1 - mats of sedum plants rolled out on to the roof
             membranes usually on about 2cm of growing medium. Such roofs
             give an instant green effect. Though this system has intrinsic nature
             conservation value as a green space, the benefit to biodiversity is
             less than the other 2 systems described below.

                                                                               G. Kadas

1 Sedums are succulents widely used in green roofs as they absorb rain water & Ecology Consultancy Ltd                                                 8
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          2. Substrate based roof - 7cm of crushed recycled brick is placed on
          the green roof system and plug planted with sedums or with sedum
          mats applied. There is a misconception that green roofs are made of
          turf. Although some green roofs are made of turf this is not generally
          the case.

                                                                        D. Gedge & Ecology Consultancy Ltd                                          9
Green Roofs – Benefits and cost implications
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          3. Green/Brown roofs for biodiversity – these are similar to the latter, but
          can in some cases use recycled aggregate from site and are generally
          left to colonise naturally or are seeded with an annual wildflower mix or
          local seed source. & Ecology Consultancy Ltd                                                10
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4.0 Benefits of Green Roofs

          Green roofs provide a number of important environmental benefits.
          These benefits can help to off set the initial installation costs in certain

               •    Green roofs provide thermal insulation and therefore energy
                    costs savings and consequent reduction in carbon dioxide
               •    Plant activity on green roofs reduces the amount of carbon
                    dioxide in the atmosphere.
               •    Green roofs can help to reduce the production of ozone by
                    reducing the heat island effect and by absorbing airborne
               •    Green roofs act as noise barriers and are sufficient to provide
                    noise insulation for buildings under flight paths and around
               •    Green roofs, if designed appropriately, can provide valuable
                    wildlife habitat in cities and help meet local, regional and
                    national biodiversity targets
               •    Green roofs reduce the effect of the urban heat island effect
               •    Green roofs significantly reduce storm water run off from
               •    Green roofs provide visual amenity to green space
               •    There is evidence that access to visual green space can have
                    positive effects on health.
               •    Innovation in the UK in the use of recycled secondary
                    aggregates as growing mediums can help meet targets to
                    reduce secondary aggregate waste.

4.1      Energy Conservation – improved thermal performance

          Green roof systems are recognised as providing greater thermal
          performance and roof insulation for the buildings they are laid on. This
          can vary depending on the time of the year, and the amount of water
          held within the system.

          Cooling [summer] – poorly protected and insulated roofs can lead to
          substantial overheating of spaces beneath them. This can lead to the
          need for increased air-conditioning. A green roof not only acts as an
          insulation barrier, but the combination of plant processes
          [photosynthesis and evapotranspiration] and soil processes [evapo-
          transmission] reduces the amount of solar energy absorbed by the roof
          membrane, thus leading to cooler temperatures beneath the surface.

          Research by Nottingham Trent University has shown the following: & Ecology Consultancy Ltd                                                11
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                    Mean daily temperature                                 18.4°C
                    Temperature beneath membrane of normal roof            32.0°C
                    Temperature beneath membrane of green roof             17.1°C

          A study conducted in Chicago, USA, recently estimated that building
          energy savings to the value of $100,000,000 could be saved each year
          if all roofs were greened, as the need for air conditioning would be

          Thermal Insulation [winter] – green roofs can help to reduce heat loss
          from buildings during the winter when root activity of plants, air layers
          and the totality of the specific system create heat and thereby provide
          an insulation membrane. However, the efficiency of green roofs as
          thermal barriers is dependent on the amount of water held within the
          system. Water retention can increase the amount of heat lost through
          the system and therefore any efficiency gains are dependent on daily
          conditions. Therefore, it is difficult to provide accurate figures on the net
          effect of green roofs on energy efficiency during the winter months.

          The study at Trent University on the temperatures under membranes of
          standard roofs and those under green roofs also showed that green
          roofs appear to have a positive effect in winter.

                    Mean Temperature                                       0.0oC
                    Temperature under membrane standard roof               0.2oC
                    Temperature under membrane green roof                  4.7oC

          This shows that green roofs do have the ability to affect the
          temperature and insulation properties of roofs, though this varies
          according to the daily condition of the roof. The potential for the cooling
          and thermal insulation properties of green roofs can have costs benefits
          for building owners/managers [See Cost Benefits].

4.2      Reduction in Carbon Dioxide

          Reducing the fuel costs of the buildings that have green roofs will lead
          to a reduction in the production of carbon dioxide. This reduction could
          be further increased if solar panels were installed on the roof. Green
          roofs are known to increase the efficiency of solar panels by acting as a
          cooling agent.

          Furthermore, the plants on a green roof also reduce the amount of
          carbon dioxide in the atmosphere through their biological activity.

4.3       Air Quality

          Extensive planting within cities is now widely recognised as a means of
          improving air quality. Green roofs contribute to the reduction of a & Ecology Consultancy Ltd                                                 12
Green Roofs – Benefits and cost implications
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          number of polluting air particles and compounds not only through the
          plants that are present, but also by deposition on the growing medium.

          •    Plants through photosynthesis reduce carbon dioxide in the
               atmosphere and produce oxygen;
          •    Green roofs reduce the heat island effect, which is the main cause
               of ozone production;
          •    Plant roofs remove heavy metals, airborne particles and volatile
               organic compounds;
          •    Being absorbed into the green roof system these polluting particles
               do not enter the water system through surface run off leading to
               improvement in water quality.

4.4       Noise and sound Insulation

          The combination of soil, plants and trapped layers of air within green
          roof systems can act as a sound insulation barrier. Sound waves are
          absorbed, reflected or deflected. The growing medium tends to block
          lower sound frequencies whilst the plants block higher frequencies.

          The amount of sound insulation is dependent on the system used and
          the substrate depth. A green roof with a 12 cm substrate layer can
          reduce sound by 40dB and one of 20 cm by 46-50dB. A study by Kalzip
          [] compared sound insulation of their standard
          unvegetated roof system with that of the Kalzip vegetated ‘Nature

                 Standard unvegetated               33dB

                 Vegetated [dry]                    41dB

                 Vegetated [wet]                    51dB

                 100mm Concrete Wall                43dB

          This suggests that a green roof can reduce sound by 8dB compared
          with a conventional roof system. This could be particularly important in
          areas of high noise pollution, for example, on the approaches to
          airports as the reduction in levels is sufficient to provide noise
          insulation to buildings under aircraft flight paths.

4.5       Biodiversity and Wildlife

          Green roofs are intrinsically of greater benefit to biodiversity than more
          traditional roofing methods. Many green roof manufacturers promote
          green roofs as benefiting wildlife, but with little evidence to demonstrate
          this. Of course ‘off the shelf’ green roof systems do provide benefits for
          wildlife compared to non-green roofs, but research in Switzerland and & Ecology Consultancy Ltd                                               13
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          in London shows that green roofs need to be designed to meet specific
          local biodiversity conservation objectives.

          Swiss research
          Detailed research into biodiversity and green roofs has been
          undertaken since 1997. This research was specifically driven by
          concern over the impacts of new developments on brownfield land in
          the city. Such land has been recognised as important for a number of
          national scarce beetles and rare spiders. These species were originally
          associated with Rhineland alluvial gravel habitat, little of which remains;
          consequently they found refuge on brownfield sites in Northern
          Switzerland. Could green roofs be better designed to provide refuge for
          such species as new developments encroached on their habitats?

          A number of design principles were arrived at:

            i. The use of local substrates as growing mediums on green roofs
               helped replicate the conditions at ground level.
           ii. Varying the depth of the substrate provided microhabitats for rare
               spiders and beetles associated with brownfields in the city.
          iii. Planting with a local seed mix.
          iv. The placing of objects associated with natural habitats such as
               dead wood and old branches increased the biodiversity of the roofs.

          Around the same time the term ‘brown’ roof was coined to ensure that
          where green roofs are to be placed in developments as mitigation for
          brownfield biodiversity issues, these roofs would not use ‘off the shelf’
          solutions but be designed specifically for the biodiversity that was to be
          mitigated for.

                                                                            D. Gedge & Ecology Consultancy Ltd                                               14
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          The design of such roofs is based on the research undertaken by Dr.
          Brenneisen in Basel and continuing investigations in to roofs in London.
          Much of the work in London has arisen as a result of the London
          Biodiversity Partnership’s black redstart action plan. The plan estimates
          that an area greater than 100,000m2 of roofs is to be built as mitigation
          for this species. In many cases ‘off the shelf’ solutions are to be used.
          However, a number of roofs are being designed specifically to meet the
          needs of the black redstart.


          Research in London since 2002 has also shown that some green roofs
          in London are providing refuge for a number of nationally rare and
          scarce species. However, ‘off the shelf’ systems are not, as yet,
          providing the ecological requirements to mitigate for brownfield habitats
          and other well-drained low nutrient habitats.

          Interestingly, research from 2003 has shown that a green roof with a
          sedum mat on 75mm crushed brick is more species diverse than roofs
          with just sedum mats, and that the species diversity is closer to that of
          a nearby brownfield habitat.

          Research in the UK on biodiversity is continuing and a more detailed
          assessment of how different green roof systems perform in terms of
          biodiversity should be available in the next few years. This has
          demonstrated the need for many more bespoke roofs to be designed in
          order to meet specific biodiversity benefits. In addition, there is a
          growing body of research that shows these roofs may also provide
          better environmental benefits for some situations.

          It is likely that green roofs can be designed to meet a number of
          national, regional and local biodiversity action plan targets. Skylark
          (Alauda arvensis) a UK Biodiversity Action Plan [BAP] species are
          known to breed on green roofs in Germany along with other notable
          species such as oystercatcher (Haematopus ostralegus), ringed plover
          (Charadrius hiaticula), little ringed plover (Charadrius dubius) and
          common tern (Sterna hirundo). & Ecology Consultancy Ltd                                             15
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          In a Birmingham context there are a number of local BAP habitats and
          species plans that could benefit from green roofs: grasslands,
          heathland, wall butterfly, dingy skipper, skylark, little ringed plover and
          black redstarts. The latter has been the driving force in many ways for
          green roofs for biodiversity in London. Green roofs will only meet the
          specific conservation requirements with appropriate design.

4.6       Urban Heat Island Effect [albedo effect]

          The urban heat island effect is the difference in temperature between
          urban areas and the surrounding countryside. In large cities this can as
          much as a 5oC difference between the city centre and the rural
          environs. Urban areas have large areas of hard surfaces that absorb
          solar radiation and reflect this heat back into the atmosphere. This is
          referred to as the albedo effect. Any reduction in this effect can have a
          positive effect on smog and airborne particles in the atmosphere.

          Roof areas are a significant part of urban hard surfaces. Plants on
          green surfaces absorb heat and utilise it through evapotranspiration.
          Therefore, green roofs play an important role in reducing urban
          temperatures, and subsequent improvements in air pollution/smog, as
          associated with the albedo effect.

          In Tokyo the albedo effect increases the humidity within the urban area
          and this, with increased air pollution, is one of the main reasons for the
          growing tendency for very complex intensive green roofs on many
          buildings in that city.

          In many parts of the USA there is growing interest in this benefit of
          green roofs. Research by NASA in Atlanta has compared temperatures & Ecology Consultancy Ltd                                               16
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          of different surfaces. On a typical Atlanta day with maximum air
          temperature of 25°C (77°F) the following temperatures were recorded:

               •    Tree shaded grass               28°C
               •    Tree canopy                     21°C
               •    Asphalt in full sun             50°C
               •    Membrane roof surface           52°C

          Research at Trent University has found on a typical day with a
          temperature of 18.4oC a normal roof surface temperature was 32oC
          while that of a green roof was 15oC.

          The reduction in the protection of photochemical smog and subsequent
          improvements in air quality needs to be recognised as a powerful
          planning ‘tool’ and potential mitigation for polluting developments. Local
          Authorities may include green roof plans as part of their commitment to
          Air Quality Management Areas [AQMA].

4.7       Storm water Amelioration

          Green roofs store rainwater in plants and their growing medium, and
          evaporate water into the atmosphere. The amount of water that is
          stored on a green roof and evaporated back is largely dependent on
          the growing medium, its depth, and the type of plants used. In summer
          green roofs can retain 70-80% of rainfall and in winter they retain
          between 25-40%.

          In Germany, the world leader in green roofs, 25 million m2 of green
          roofs were installed between 2000 and 2001. This is primarily a result
          of legal requirements in certain ‘landers’ for roofs to be installed for
          their benefits in alleviating storm water run off. In Portland, Oregon –
          one of the leading cities in USA for installing green roofs – green roof
          policies are being driven over concerns of storm water run off and the
          consequences of it on water quality in rivers, and consequently the
          continued health of rivers for salmon [a key cultural indicator].

          Green roofs also reduce and delay run off during times of heavy and
          prolonged precipitation. A study in Germany has shown that during a
          10mm rainstorm, 200 litres of rainwater fell on an 18m2 extensive green
          roof and only 15 litres actually passed from the roof to the ground.

          Green roofs, therefore, reduce the impact of run-off on the storm water
          drainage system, and reduce the likelihood of local flooding.

4.8       Green space

          The value of green spaces to people living and working in towns and
          cities has increasingly been recognised by Government. The work of
          the Urban Green Spaces Taskforce (Green Spaces, Better Places, & Ecology Consultancy Ltd                                              17
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          2002) demonstrated the various benefits that green space provide,
          such as ecological function, visually softening the built environment,
          supporting biodiversity, aiding people’s mental and physical health, and
          providing a communal focus and sense of place. Government has
          subsequently launched a raft of new policies, initiatives and funding to
          promote the good design and management of green spaces.

          English Nature has published research that suggests that an
          accessible natural green space should be no more than 300 metres
          from where anyone lives in order to meet people’s needs for contact
          with nature. Evidence suggests that regular direct contact with natural
          green space (and elements of the natural world such as birdsong and
          seasonal colour change) is good for people’s health (see below).

          There is a need for increased densities in urban residential
          development (>30 dwellings per hectare), which could result in
          terrestrial green space being reduced or lost. In the urban core the
          provision of green space is usually already severely limited, partly
          through historical circumstances, and more recently because of very
          high land values; this makes the creation of new green space important
          but difficult. Given the nature and pressures of urban regeneration, the
          creation of new spaces has to meet a number of interests; these
          generally result in highly formal spaces with little ecological benefit.
          Creating low-maintenance, terrestrial, naturalistic green spaces in the
          urban core is not popular; green roofs may provide one solution.

          Green roofs can provide both visually and physically accessible green
          space. Roofs are largely visually ‘dead’ and unappealing and their
          appearance to those overlooking them can be softened by vegetation.
          There are instances where the sole justification of a green roof
          installation is for visual aesthetics. Areas of green roofs can also
          provide accessible space for people to enjoy, and some can be
          landscaped to extend existing green space, for example at Canary
          Wharf station on the Isle of Dogs, London.

          Roof gardens and terraces are options for smaller buildings and have
          some historical ancestry. The Berlin roof gardens of the 19th century,
          have been adopted on similar housing blocks in Britain (for example,
          Peabody Trust’s Balderton Flats in Mayfair) and were one of the
          inspirations for the first modern green roof in the UK, at Derry & Toms,
          Kensington, 1938, which still serves as a garden, albeit with limited
          public access. Roof gardens are increasingly being proposed for new
          office and housing developments.

          Large areas of accessible green roof space can be created if the
          building is large enough, for example, above Cannon Street Station in
          the City of London [intensive], and at Chicago City Hall [extensive].
          More ‘extreme’ examples include a golf course on a roof in the USA.

          The key issues that need to be considered in providing accessible open
          space are health & safety (the need for a external rail or fence), over- & Ecology Consultancy Ltd                                            18
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          looking neighbouring properties (a material planning consideration),
          access to and from the roof-space, load-bearing (if the proposed
          numbers of people are to be more than a few), and management. The
          existence of green roofs that provide this function suggest that these
          issues can usually be easily addressed.

4.9       Health

          There is a growing body of evidence that the visual and physical
          contact with natural greenery provides a range of benefits to people.
          These include both mental benefits (such as reduction of stress) and
          physical benefits (including the provision of cleaner air). Access to
          green space can bring about direct reductions in a person’s heart rate
          and blood-pressure, and can aid general well-being. A Texan study of
          post-surgery recovery in hospitals demonstrated that recovery was
          quicker and with less chance of relapse if patients could look out onto
          green space. A number of American hospitals have subsequently been
          redesigned to bring these benefits to patients, and have been rewarded
          with greater patient ‘through-put’. A roof on the Kanton Hospital in
          Basel was redesigned 20 years ago by vegetating it, because it was felt
          that patients in intensive care would benefit from looking out onto this
          rather than the grey-space of before. A few community hospitals in the
          UK are now being designed with a greater consideration of green-
          space provision, and the good-practice work on hospital design being
          developed by Commission for Architecture and the Built Environment
          [CABE] is likely to further this.

          The thermal benefits that green roofs provide may also have indirect
          benefits for people living or working within the buildings. This has not
          been researched, but anecdotal evidence from Germany in the late
          1990s is of interest. In a survey of staff absence from sickness at the
          Bundepost offices in Stuttgart, it was shown that staff in one building
          demonstrated significantly lower absences than those in others. The
          only change in the 4-year period that could be identified was that one of
          the buildings was given a green roof; this building supported lower staff
          sickness levels. It is possible that the green roof reduced the fluctuation
          of daily mean temperatures within the upper levels of the building,
          and/or the vegetation helped cool and moisturise in-going air near
          ventilation ducts.

          In the past 2-3 years, possibly picking up on the increasing interest in
          green roofs and Government’s interest in green space, developers are
          increasingly showing green roof space as a component of their new
          commercial development proposals. The provision of accessible green
          roof space for future workers appears to be gaining currency, and could
          help off-set the likely constraints of green space provision on the
          ground. & Ecology Consultancy Ltd                                               19
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4.10      Recycled Materials

          A number of materials used in green roofs, such as the membranes
          and growing mediums, are from recycled sources and include crushed
          brick. In London, uniquely, there has been a move to use recycled
          secondary aggregate as the growing medium, preferably from the
          original site.

          This reduces the need for waste disposal to landfill and reduces the
          transport miles/distances for used for disposal of waste. This meets UK
          government targets for the reuse of secondary aggregates and where
          reuse from site can reduce the impact of lorries in terms of importation
          and exportation of materials.

4.11      Use of Sustainable Building Materials in Green Roofs

The scope for inclusion of sustainable building products or environmentally-
friendly building materials is considerable. Bearing in mind that materials from
recycled sources are now widely and easily available it is not difficult to
minimise the overall environmental impact of the construction of a green roof
itself. This is done through using materials from reused or recycled routes
and those that contain low-embodied energy (the energy contained in a
product which was put in through the manufacturing process, the lower being
less environmentally damaging).

Eastside has a website resource set up at: www.birmingham-, where a contractor, designer, architect can search
for these materials, which are also locally available. The local availability of
materials is important in reducing transport distance of materials, fuel use and

The following options need to be considered in the materials selection and
specification: -

Timber for roof decking should all be FSC certified (that is validated by the
Forest Stewardship Council as from a managed forest), or reclaimed.

Vapour barriers, root barriers and drainage trays are available in recycled
plastics materials that have less environmental impact that newly
manufactured plastics.

Any rubble and crushed brick used should be sourced from demolition sites or
a local secondary recycling plant.

Insulation materials such as cellulose fibre are preferable as being naturally
sources rather than manufactured polystyrene, mineral wool or glass fibre

Waterproofing layer materials (i.e., Hydrotech) are also sourced from recycled
materials. & Ecology Consultancy Ltd                                            20
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In addition designers and architects should consider whole-life costs of the
roof, not just using the cheapest available materials at the time. Those
materials that are selected to last the “whole-life” of the roof (i.e., they may be
initially more expensive but as they need replacing less, and are more durable
they outlast the cheaper products).

The following resources will be of use:- (see links page)

Green Building Handbooks 1 & 2 by Woolley, Kimmins and Harrison.
BRE’s Green Building Guide to Specification. & Ecology Consultancy Ltd                                             21
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5.0 Cost Benefits of Green roofs

          Although green roofs are more expensive to install at the outset, the
          benefits of such roof systems can provide substantial economic
          benefits over time and therefore have a positive effect on whole life
          costs. As whole life costing for new development is emerging as an
          important tool for sustainability, the fiscal benefits of a green roof
          during the life of a building after construction are likely to become more

5.1       Extended Roof Life

          Green roof systems provide protection to roofing membranes from the
          effects of UV light and frosts, and therefore lead to a longer material life
          span. It is generally accepted that a greened roof can double the
          material life. ‘Derbigum’, a commercial waterproofing system, has a 30-
          year life; with an extensive green roof system [cross brick/sedums] this
          would have a 60-year life. This results in a cost benefit to the client over
          the years.

5.2       Fuel Savings

          Green roofs have a positive effect in terms of thermal insulation
          through their ability to cool buildings and insulate them during the
          winter [dependent on daily conductance of the green roof].
          The German Green roofing manufacturer Zinco International has
          estimated that green roofs can contribute to savings in fuel heating
          costs of 2 litres of fuel oil/m2/year in Germany and an industrial plant in
          Frankfurt [Possman Cider Cooling and Storage Facility], which had a
          green roof installed recovered the cost of the green roof in 2-3 years
          through the savings in heating and cooling costs, and the reduction in
          industrial equipment associated with these activities.

          A conversation with a building services manager in London revealed
          that the application of a retrofitted green roof on a building had reduced
          the need for cooling/heating of industrial plant in the floor beneath.
          Since the green roof has been installed, cooling and heating fans have
          not been used. It is estimated that about 25.9 MW per year is being
          saved. Using current electricity rates this is approximately a £4,300
          saving per year. If the green roof had been installed as part of the
          original design of the building and the ability of the green roof to reduce
          cooling and heating requirements had been known, there would have
          been a potential saving of £10,000 due to reduction in the need to
          replace heating and cooling equipment in the floor in question. & Ecology Consultancy Ltd                                                22
Green Roofs – Benefits and cost implications
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  5.3 Reduction in costs of drainage

          There are potential savings for developers and owners in that a green
          roof installation could reduce the number of drainage outlets. A number
          of developers and green roof manufacturers have pointed out that
          quantity surveyors are unlikely to factor in these cost benefits, as they
          tend to separate the costs of roofs and drainage. However, depending
          on the size of the roof and the height of the building, the cost benefit of
          drainage outlet savings could significantly offset the cost of a green

          In out of town developments the reduction of storm water drainage
          solutions at ground level could also be reduced, though industrial
          lightweight buildings are unlikely to be structurally able to take a green

5.4       Cost savings through the re use of secondary aggregates.

         The reuse of local aggregates can provide a cost saving during the
         construction of roofs within a development. The cost of growing media
         is in the region of £10 -£15/m2. Although there will be a cost incurred if
         materials such as brick and concrete are used from site in terms of
         crushing to the required grade, screening and transportation within site
         this will be minimal. A 1000m2 green roof could potentially save the
         developer £10,000 off the cost of the materials needed on the roof.
         Inverted roofs require hard landscaping to weigh down floating
         insulation. This is replaced by the growing medium if a green roof is
         used. The re-use of local aggregates can mean that green roofs are
         competitively priced with conventional inverted methods. & Ecology Consultancy Ltd                                               23
Green Roofs – Benefits and cost implications
March 2004

6.0 Costs

          Although there a number of published costs in documents available on
          the internet, a number of agents of leading green roof manufacturers
          were interviewed during the course of the research into this report to
          provide a more comprehensive picture of contemporary costs. The
          following costs are ball-park figures as the cost per metre is dependent
          on a number of factors. The costs include the most important element
          of a green roof system; the waterproofing element. Most published
          costs do not necessarily relate to standard roofing costs. All the costs
          presented here must be considered as ball-park figures.

6.1       Factors affecting cost

          Costs for green roofs are notoriously difficult to assess, as there are a
          number of factors affecting price per metre. These are:

          1. Size of roof. There is an economy of scale here as small roofs can
             be very expensive. Such an example is a small roof in the centre of
             London, which cost £185/m2. The larger the area the cheaper the
             roof will cost [see case study 2: £55-60/m2.

          2. Height of the roof. This will affect the price in terms of the cost of
             raising the elements to roof level

          3. Type of green roof required. In terms of extensive green roofs an
             instant green effect though the use of sedum mats will be more
             expensive than planted sedum plug plants. The cheapest option is
             generally hydro seeding but this will take time for the plants to
             establish the ‘green’ effect. Roofs designed for biodiversity may well
             be cheaper as they will generally be seeded with an appropriate
             seed mix or allowed to establish their vegetation through natural

          4. Initial maintenance and establishment costs. Though sedum plug
             planted systems can cost less per m2 there will be a cost in terms of
             establishing the roof over the first 2 years in terms of irrigation and
             weeding etc.

          5. Type of waterproofing and insulation used. Different waterproofing
             systems require different applications and therefore there is a
             difference in labour costs.

          6. Other factors. Roof elements that intrude above the roof such as
             outlets, roof lights and industrial plant and other additions such as
             access hatches, safety lines can lead to increase in price per metre
             squared. & Ecology Consultancy Ltd                                              24
Green Roofs – Benefits and cost implications
March 2004

          7. Involvement of manufacturers and contractors. Too often green
             roofs are inaccurately priced as suppliers and contractors are not
             given detail plans at an early stage or the roof has already been
             structurally designed. The latter limits which system can be applied
             and therefore can increase cost.

          8. Installation methods. There is often a need to ensure that
             installation is properly supervised and monitored to ensure that
             specific design and specifications are followed. This is particularly
             important where roofs have been designed specifically for

6.2       Ball park figures for costs

          The product and installation costs presented here have been gained
          through interviews with representatives of four of the leading green roof
          suppliers. There are other forms of roofs such as steel roofs [see case
          study 8] but the basic roof system that most green roofs are applied to
          are either single ply or inverted. Single ply roofs generally have the roof
          insulation beneath the waterproofing and inverted roofs above the
          waterproofing. In this case the insulation is weighed down by a hard
          landscaping element or a green roof element.

          Single Ply
                                                                               Green Roof
          Components             Standard Low   Standard High Green Roof Low      High
          Standard                    35             50             35             50
          Moisture mat etc                                          15             30
          Plants                                                    10             30
          Total                         35           50             60            110

                                                                               Green Roof
          Components             Standard Low   Standard High Green Roof Low      High

          Waterproofing                 20           25            20             25
          Insulation                    15           16            15             16
          Landscaping                   12           25
          Growing Medium                                           10             12
          Plants                                                   10             30

          Total                         47           66            55             83 & Ecology Consultancy Ltd                                                   25
Green Roofs – Benefits and cost implications
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          Biodiversity Design Inverted Green Roof using site sourced growing

          Components           Standard Low    Standard High Green Roof Low Green Roof High

          Waterproofing                20           25             20             25
          Insulation                   15           16             15             16
          Landscaping                  12           25
          Fleece                                                   1               5
          Seeds                                                     ?              ?
          Total                        47           66             36             46

          This shows that the cost of green roofs on an inverted roof system,
          especially when designed along biodiversity design guidelines, is not
          necessarily economically prohibitive and can actually be cheaper than
          using conventional hard landscaping finishes.

6.3       Published Costs

          There are number of publications that list the various costs of green
          roofs. This section gives an initial overview of these costs. It provides
          details of a number of green/brown roof projects in London and
          highlights potential savings. It also provides details of interviews with a
          number of green roof company representatives to establish the average
          costs of different green roof systems depending on size. These costs
          will provide only a benchmark, as every roof needs to be assessed on
          an individual basis.

          This section also compares these costs with more conventional roofing
          methods. The focus of this costs comparisons will be on commercial
          building blocks with flat roofs

          Corporation of London, Green Roof Advice Note
          In 2003 the Corporation of London published a green roof advice note.
          This document provides the costs of 4 sedum roofs.
          The average cost of the roofs was approximately £121/m2. More
          information can be found at:


          English Nature Report
          ‘Green Roofs: their existing status and potential for conserving
          biodiversity in urban areas’ was published by English Nature in 2003.
          The report provides an overview of the average costs in a number of
          countries. The costs are for extensive sedum matted green roofs. & Ecology Consultancy Ltd                                                     26
Green Roofs – Benefits and cost implications
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                    USA                        $150[£100] - $200[£133] /m2
                    Germany                    20-40 Euros/m2
                    UK                         £85 - £93/m2

          The variation of costs is generally down to the size of the roof: the
          larger the roof the lower the costs. More information can found at:

          Black redstart website, London Biodiversity Partnership
          The only published costs of a green/brown roof currently available are
          published on the London Biodiversity Partnership’s black redstart
                 Laban Dance Centre                       £26.86/m2

          The website also points out that the cost could have be £21.58/m2 if the
          roof had been applied at an earlier date and therefore not incurred the
          cost of a crane specifically for the installation of the green/brown roof
          growing medium. More information can be found at:

6.4       Conclusions

          As the above demonstrates there is a degree of variety in costs per
          metre due to the factors outlined. It is worth noting the costs for
          individual projects in the case studies outlined in Section 9. & Ecology Consultancy Ltd                                             27
Green Roofs – Benefits and cost implications
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7.0 Barriers to Green roofs

          There are a number of perceived problems regarding green roof
          installation aside from the capital costs. A study in London in 2002
          identified a number of these by interviewing a number of professionals
          and interested parties.

7.1       Structural Issues

          One of the perceived barriers against green roofs is the structural
          implication to the building. The London study contacted a number of
          professionals and asked them to agree with the statement: ‘the physical
          structure of the many buildings prevents the establishment of green
          roofs.’ These were the responses:

                     OCCUPATION                      % AGREED
                     Environmentalist                   67
                     Architects                         40
                     Planners                           33
                     Engineers                          27
                     Developers                         92
                     Ecologists                         13
                     Other                              50

          What is interesting here is that 92% of developers had concerns
          compared with only 27% of engineers? A number of structural
          engineers the author of this report has talked to have noted that it is not
          much of a problem in theory, but that many engineers are unfamiliar
          with green roofs and tend not to want to deal with things they are not
          familiar with.

          Any landscape feature on a roof will have loading implications and the
          saturated weight of any such features must be used to calculate the
          structural load. Below is a table of saturated weights of various
          landscape elements including green roof systems. This have been
          obtained from Zinco International and calculated according to
          standards outlined in ‘German National Standard DIN 1055 – Design
          Loading for Buildings. The load values are for saturated weights.

                     Gravel Surface               90-150 Kg/m2
                     Paving slabs                 160 –220 Kg/m2
                     Vehicle Surface              From 550 Kg/m2
                     Extensive Green roof         60 –150 Kg/m2
                     Intensive green Roof         200 –500 Kg/m2

          It is interesting to note that many inverted roofs are covered in paving
          slabs [hard landscaping] in order to ballast out the insulation. The use & Ecology Consultancy Ltd                                               28
Green Roofs – Benefits and cost implications
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          of an extensive green roof system would have a negligible effect on the
          structural load in this instance.

          Recently a structural report for a current commercial building in London
          allowed for an extensive green roof to be applied on top of the paving
          slabs of an inverted roof without any negative structural implications.
          The depth of substrate to be used is between 2-8cm.

          Roofs designed as single ply are likely to be less structurally robust
          than inverted systems. Unless such systems are structurally
          strengthened, a simple extensive sedum mat may well be the only

7.2       Maintenance

          Another perceived barrier is the cost of maintaining a green roof. This
          cost though is relative to what kind of green roof is installed and how
          the owner wishes it to be used. Intensive green roofs can generally be
          considered as elevated parks and therefore require similar
          maintenance. Extensive green roofs require less maintenance and in
          general this can add only about £1/m2 per year more to the cost of
          maintaining a standard roof.

          However, it is worth noting that in Germany most companies stop green
          roof manufacturers’ recommended maintenance regimes after a
          number of years as they have fulfilled the planning criteria and have let
          the roofs go ‘wild’. They merely visit the roof once a year to ensure that
          problematical shrubs and trees that could impact on the membranes
          have not colonised. This is generally a safety precaution, as green
          roofs are installed with root membranes and as they have shallow
          growing mediums, such plants would wither in time.

          In general therefore extensive green roofs should be reasonably self-
          maintaining unless the client requires the roofs to look ‘manicured’.

7.3       Guarantees

          There is an issue of guarantee and warranty. Green roof manufacturers
          provide a guarantee for the waterproofing, but also provide a guarantee
          in terms of the green roof, specifically for plant survivability. Roofs
          designed for biodiversity will, generally, not be given a guarantee in
          regard to the green roof system. Often this is worded in such a way as
          to suggest the roof will not be guaranteed, implying that neither the
          waterproofing nor the green roof will be guaranteed. In fact it is the
          green roof, i.e. plant survivability that is not being given a guarantee.
          However, the wording can incline a developer or architect to be
          persuaded to purchase the whole system. It is important to establish
          what is guaranteed and what is not. & Ecology Consultancy Ltd                                              29
Green Roofs – Benefits and cost implications
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7.4       Guidance and Support

          The London study also identified that most professionals were keen to
          see more green roofs, but many respondents to the survey cited as a
          barrier a lack of public guidance, information and government support.
          Understanding of green roofs is generally limited to the individual
          companies and a few enthusiasts. Independent advice is not easy to
          come by.

          In Britain there are no government incentives or other support for green
          roofs and this is a major barrier [Kortright, 2002]. In Germany there are
          direct incentives and financial investment, which has seen the industry
          grow by 10-15% annually over the past decade.

7.5       Aesthetics

          Although not mentioned in the London Study, a key concern within the
          green roof industry and development professions is aesthetics. Green
          roofs are intrinsically ‘living roofs’. This can give architects and
          developers cause for concern in knowing what they are going to get in
          terms of look from a green roof. Green roofs will never always look like
          the glossy images taken on a perfect spring day, even if they have the
          highest maintenance. However, as has been pointed out above, in
          general, once an extensive green roof has been established concerns
          about aesthetics become less of a factor. More often than not, in
          Germany, roofs are left very much to natural processes.

7.6       Other Issues

          As in many other situations the failure to predict the impacts of actions
          can lead to inappropriate activities being undertaken. A case the
          authors are aware of is a green roof that was not as green as it should
          have been. The roof was covered in fertiliser [chicken manure].
          However, the water run off from the roof was being reused as grey
          water. The consequent build up of bacteria in the grey water prohibited
          its reuse. & Ecology Consultancy Ltd                                             30
Green Roofs – Benefits and cost implications
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8.0 Policy Framework for Green Roofs

8.1       Introduction

          There are no specific planning or building policies to encourage the
          design and implementation of green roofs in the UK. National planning
          policy neither directly refers to green roofs, nor implicitly encompasses
          them in its directives and objectives to deliver development.

          Conversely there are no policies that are directed towards preventing
          the design and installation of green roofs, and the emerging emphasis
          on sustainable development is bringing about a revision of planning
          policies that further the principles behind green roofs. In addition the
          Government’s urban agenda, and its focus on high-density, quality-
          designed development, with an increasingly environmental sensitivity,
          makes green roofs more likely to make an important contribution
          towards meeting a number of these objectives.

          The work of and others is focussing on the policy deficit
          on green roofs, and will be advocating for the need to develop and
          adopt policies to enable their installation, both for new development
          and existing buildings. In parallel is our recognition for the need to
          develop standards for green roofs, to ensure that quality design and
          performance objectives are met. Green roof design standards are still
          developed by a largely unmonitored industry furthering a ‘product’ with
          which most people are unfamiliar. It is not easy for clients and planners
          to be able to refer to any existing standards, or to establish criteria for
          the design of green roofs in development plans. The larger green roof
          manufacturers in the UK meet the German FLL Standards, but no one
          from outside the industry is monitoring these (or is able to) or the green
          roofs installed by any other manufacturer.

          At a time when the desire for green roofs is likely to increase
          exponentially over the next few years, the need to prevent systems
          failing (and thereby affecting the concepts and benefits of green roofs)
          is an issue we take seriously. Building Regulations need to take
          account of green roof systems, and the need to establish minimum
          industry standards or certification are issues that is to
          pursue in the near future.

8.2       National Planning Policy Guidelines

          Although there is no national guidance on green roofs for local
          authorities to work to, there are a few tangential hooks on which to
          hang green roof proposals. The strongest of these, ironically, are found
          within PPG9 (Nature Conservation) and PPG25 (Development and
          Flooding), although PPG3 (Housing) has some useful references. In
          Appendix 1 we detail the policy statements of relevance. & Ecology Consultancy Ltd                                               31
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          It is clear that the continuing review and revision of planning policy
          guidance (to shorter statements, and more detailed accompanying
          guidance) is beginning to take stronger account of sustainable
          development principles, and that through consultation there are
          opportunities to advocate specific references to green roofs.

8.3       Urban Policy

          Britain’s population is rising. Emigration from our cities to the
          countryside is more than matched by inward immigration from outside
          Britain. With an estimated 3.8m households to be accommodated by
          2021, there is concern about where these will be located. Added to this
          the wide disparities in wealth across society, the collapse of heavy
          industry, the legacy of poor planning in the 1950s-70s, and the
          demands of an increasingly urban, mobile, individualistic and multi-
          cultural population, the Government of 1997 recognised that a profound
          step-change was required to manage these tensions. It set up the
          Urban Task Force to set the ball rolling, headed up by the architect
          Richard Rogers. In 1999 they delivered a landmark report Towards an
          Urban Renaissance.

          The Government published Our Towns and Cities (the first Urban White
          Paper for over 20 years) in response in 2000. It has subsequently
          established a number of initiatives and targets to improve the quality of
          life within our towns and cities, and limit further damaging development
          in the countryside. This ‘urban renaissance’ places great emphasis on
          the development of previously developed land (‘brownfields’), of urban
          design quality, of an increase in skills, of deeper community capacity
          building, and the creation of new legislation, guidance, and fiscal tools
          to aid delivery.

          There is no reference to green roofs within the White Paper. But the
          following statements are of use: & Ecology Consultancy Ltd                                             32
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March 2004

         Better planning                 4.12 Where there is a need or opportunity for new
         and design                           development in towns and cities we must
                                              ensure that it is of the highest quality. In
                                              particular we must ensure that it:
                                           • makes the best use of the land we have
                                              available; and
                                           • is built in a sustainable way that is sensitive
                                               to the needs of people and the impact urban
                                               living has on the environment.
         The way forward                 4.20 We need an approach to the design and
                                              development of urban areas which:
                                           • makes efficient use of the available land and
                                              buildings and reduces the demand for
                                              greenfield development;
                                           • provides homes which are attractive and
                                              environmentally friendly;
                                           • encourages well laid out urban areas with
                                              good quality buildings, well designed streets,
                                              and good quality public open spaces;

8.4       Housing

          Within the mainstream, the Housing Corporation (the Government’s
          housing regulatory agency) has recently shown leadership in following
          up the Government’s Construction Task Force’s report and promoting
          innovation in the sector. The Housing Corporation has established an
          Innovation & Good Practice grant fund. Importantly this has funded the
          Sustainable Homes project, which promotes awareness of sustainable
          development issues for housing associations. It has developed the
          EcoHomes rating for environmental performance, which forms part of
          the Building Research Establishment (BRE) suite of environmental
          assessment tools. Sustainable Homes (SH) has published a Guide to
          EcoHomes, and further work into environmentally friendly housing
          during construction and occupation is to be carried out.

8.5       Parks and Open Spaces

          Government has, belatedly, started to make amends and hence the
          political profile of parks and green spaces has risen significantly.
          Subsequent to a number of Inquiries, research reports and the work of
          an Urban Greenspaces Task Force (2001-02), it has published new
          guidance, allocated monies, and established a new unit within its
          architectural and urban design watchdog, the Commission for
          Architecture and the Built Environment (CABE). The CABE Space unit
          was launched in May 2003, and is undertaking further research,
          promoting good practice, and seeking to enhance open space within
          the context of the urban renaissance. The anchoring of this & Ecology Consultancy Ltd                                                      33
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          championing unit within CABE offers the possibilities of demonstrating
          the role of green roofs across the architectural and green space

8.6       Biodiversity

          In 1994 the nature conservation sector in Britain entered a new
          paradigm in response to the Government’s signing of the Convention
          on Biological Diversity at the Rio Earth Summit in 1992; the UK
          Biodiversity Action Plan (UK BAP) process. Biodiversity action planning
          is a wide-ranging, cross-sectoral, targeted and costed approach to the
          conservation of priority habitats and species. It involves setting and
          delivering objectives at the national, regional and local level through
          multi-sectoral partnerships. Local Biodiversity Action Plans (LBAPs)
          should establish locally relevant objectives as well as aim to help meet
          regional and national targets.

          Birmingham & Black County Biodiversity Action Plan
          The Birmingham & Black County Biodiversity Action Plan (B&BCBAP)
          published in July 2000, is the region's response to the UK's National
          BAP. It focuses on aspects of the local wildlife resource – species and
          habitats – which are in need of protection or conservation. The
          B&BCBAP sets out a number of targets and methods for ensuring the
          continued presence of wildlife in the city and surrounding environs into
          the 21st century.

          Three key Action Plans within the B&BCBAP are of direct relevance.
          The Black Redstart action plan is one of only three LBAPs that
          addresses the rarity of this species and its distributional focus in urban
          areas (the others are in London and Reading). It has two relevant
            • Maintain existing breeding population and range in Birmingham
               and the Black Country
            • Increase the breeding population from the existing 5-12 pairs, to
               20 pairs by 2006.

          There is a Buildings & the Built environment action plan (the first LBAP
          in the UK to recognise the importance of buildings), which has four
          relevant targets:
            • Enhance the quality of the built environment for priority species
            • Raise public awareness of the importance of building and the built
               environment for biodiversity
            • Establish partnerships with landowners, the business community
               and public sector to establish ways of protecting and managing
               the built environment for biodiversity
            • Encourage sustainable treatment of groundwater, surface run-off
               and water courses

          The Urban Wastelands action plan promotes the biodiversity value of
          many post-industrial sites, some of which will be important for & Ecology Consultancy Ltd                                              34
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March 2004

          regionally and nationally scarce species (e.g. black redstart). Although
          the Action Plan contains no targets with direct relevance to green roofs,
          the provision of rooftop habitats that are analogous to the wastelands it
          seeks to conserve could help towards meeting its objectives.

          Black redstart
          Without the black redstart as a flagship, we may have got nowhere.
          This bird, which is rare in Britain, is subject to full legal protection
          during the breeding season under the Wildlife & Countryside Act 1981
          (as amended). This means that developers of the urban brownfield
          sites in which it is found to be exhibiting breeding behaviour, and the
          planning authorities to which developers have to respond, are subject
          to the conditions of the Act. Construction and/or demolition can be
          stopped if it’s found to disturb the bird in its behaviour, and developers
          should mitigate for any loss or damage of its habitat. There are
          weaknesses in the Act, and in its enforcement, but the focus on black
          redstarts in London since 1997 now means that developers and
          planners are increasingly aware of the issues and act accordingly.

8.7       Regional policy context

          The planning policy context for Birmingham and the West Midlands has
          being going through a period of review, to reflect national planning
          policy guidance. The Draft Regional Planning Guidance (RPG) for the
          West Midlands is due to be adopted shortly, replacing RPG 11 of 1993.
          It adopts a significant shift towards the principles of sustainable
          development, and although there is no mention of green roofs within it,
          there are Policies and targets for which the installation of green roofs
          can contribute.

          The Birmingham Plan, the spatial development strategy for Birmingham
          City is similarly undergoing a review. Likewise it demonstrates a
          significant shift in thinking. Policies for which are relevant to green roofs
          are listed in Appendix 2.

          The City Council has also published two other relevant strategies; a
          Nature Conservation Strategy (1997), and a Sustainable Development
          Strategy and Action Plan 2000-2005 (2000), which have
          Supplementary Planning Guidance status (see below). Both these
          acknowledge the environmental and ecological importance of the city
          centre, and the need to protect and enhance the existing resources and
          capacity wherever possible. Green roofs can make a significant
          contribution towards meeting some of these Strategies’ objectives.

8.8      The role of new regional governments

         Although there is only one regional government at present, the Greater
         London Authority, this serves as an example of how the role of such
         governments could implement the use of green roofs. The & Ecology Consultancy Ltd                                                 35
Green Roofs – Benefits and cost implications
March 2004

         circumstances in which the authors and have been
         operating have provided a vehicle to establish new policy tools to
         promote green roofs.

         The Mayor of London, who heads the GLA, has a number of unique
         duties and powers. He must prepare strategies for London on economic
         development, transport, biodiversity, energy, noise and other themes –
         and his strategies must be consistent with each other as well as the
         principles of health, equalities and sustainable development.

         The Mayor is in a unique position to help mainstream green roofs, and
         has already begun to emphasise their potential benefits across a range
         of policy areas; particularly biodiversity, energy, open space and visual

         The Mayor’s Biodiversity and Draft Energy Strategies contain specific
         policies that aim to encourage, support and drive the establishment of
         green roofs. The Draft Energy Strategy, for example, states that the
         Mayor expects planning applications referable to him to incorporate
         passive solar design, natural ventilation, borehole cooling and
         vegetation on, and adjacent to, buildings wherever site conditions make
         them feasible. He also expects all 33 London boroughs to do likewise.

         The GLA is also the strategic planning authority for London and has just
         published the London Plan, regional planning guidance that will enact
         the planning-related policies of the Mayor’s other strategies. It is a legal
         requirement that London borough Unitary Development Plans are in
         accordance with the policies in the London Plan, which states for
         example that ‘Wherever appropriate, new development should include
         new or enhanced habitat, or design (e.g. green roofs) [their
         parentheses] and landscaping that promotes biodiversity, and provision
         for their management.’

         The opportunity for individuals and organisations promoting best
         practice in sustainable development provide the first regional
         government is likely to be mirrored elsewhere in the country when
         those opportunities arise.

8.9       Local policy guidance

          Planning legislation allows local authorities to prepare Supplementary
          Planning Guidance (SPG) on matters, which it feels have relevance to
          development within their areas. With a noticeable shift from
          Government in respect of sustainability, a number of local authorities
          are preparing SPGs on sustainable building, to address issues such as
          thermal efficiency, energy & water use, construction materials, car-
          parking densities, drainage, etc.

          Supplementary Planning Guidance in Birmingham is location based,
          and includes that for Eastside (Eastside Development Framework, & Ecology Consultancy Ltd                                               36
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          2001). In London, Westminster City’s Sustainable Building SPG (2003)
          makes specific reference to green roofs, and Lewisham Council’s
          revised Unitary Development Plan (2002) contains a specific green roof
          policy. Others are beginning to take notice.

8.10      Building Regulations and Standards

          Building Regulations make no direct reference to green roofs, only to
          the construction and standards of roof construction. Neither are there
          any British industry standards to which a client may refer. Local
          authorities still require guidance to advise developers, and from which
          to make decisions. At present, retailers and various individuals have
          supplied this as circumstances dictate. A version of the German FLL
          guidelines written for a British context would be a start, but this may
          simply maintain a simplistic type of green roof, with not all of the
          benefits another type of green roof could provide if the circumstances
          could allow it.

          However, concerns have been raised from some retailers that the lack
          of British standards is allowing sub-standard systems to be installed at
          a cheaper cost, with the danger that their reputation and that of green
          roofs will be damaged. There is no British trade association of green
          roof manufacturers/retailers nor is there a single source of information
          that can signpost people to the range of systems and suppliers.
          Consequently, a new British green roof website is currently being
          established by; it is hoped that this may act as a
          catalyst for an embryonic trade association, which could act as a potent
          vehicle to establish working standards, and ultimately Government
          recognition through guidance and, if needs be, incentives. & Ecology Consultancy Ltd                                            37
Green Roofs – Benefits and cost implications
March 2004

9.0 Case Studies

          The following cases studies have been draw from the experience of
 and Ecology Consultancy Ltd in London. A number of
          these roofs could be considered so-called ‘brown’ roofs. The green
          roofs have been selected to demonstrate the variety of possible
          systems and the reasons for their installation. Wherever possible a
          break down of the roof, its cost, total and comments by building owners
          and/or developers and/or contractors has been included.

          All of these roofs have already been installed or are about to be
          installed. Projects, which are as yet incomplete, have been included as
          they specifically highlight issues associated with the brown/green roof
          subject. The authors were unable to get details of the few green roofs
          in the West Midlands and all of the roofs included, other than Rolls
          Royce case study, are in London. This is primarily a result of the
          authors’ familiarity and access to these projects. The term brown roof
          originated out of work on the London Biodiversity Partnership’s black
          redstart action plan [which the authors are involved with] and a number
          of these roofs have been established or are about to be established in
          the London area. The authors are keen stress that these so-called
          ‘brown’ roofs are still green roof systems [see 4.5].

          Case Studies 11 and 12 are development briefs/zones which have
          green roofs as part of their ‘vision’ or are constrained to include them in
          their master plans. & Ecology Consultancy Ltd                                               38
Green Roofs – Benefits and cost implications
March 2004

Case Study 1

Deal’s Gateway, Deptford, London SE8

                                                                   D. Gedge

Type of development
Private housing development

Reason for Green Roof
Planning condition has mitigation for nature conservation issues

Type of roof
Single Ply

Size of Green Roof
2000m2 –900m2 currently complete

Build up of Roof
Insulation [extruded polystyrene]
Hydrotech waterproofing membrane
Drainage/Irrigation mat with built in fleece
Crushed brick 80 concrete, 1cm of topsoil
Colonisation & Ecology Consultancy Ltd                                     39
Green Roofs – Benefits and cost implications
March 2004

Details of Green Roof Element
The growing medium is 80% crushed brick and 20% sourced from a local
secondary aggregate recycling company. This has been laid at a depth of
75mm covered with 1cm of locally sourced topsoil, which should filter through
into the growing medium to provide some organic element to speed up
colonisation. On to this will be placed wood, hessian rope and boulders.

The green roofs have been marginally more expensive than the other roofs on
site. It has been estimated that the green roofs cost 20% more. There is a
positive benefit of the green roof from a construction point of view, as ongoing
works on the development require construction items to be placed on the roof
temporarily. On a standard roof there would be concerns of having a negative
impact on the waterproofing system. The green roof element provides
protection for the waterproofing and therefore eases such concerns.

The roofs were completed in January 2004. One of the roofs is to be seeded
with an annual wildflower mix and the other left to colonise. & Ecology Consultancy Ltd                                          40
Green Roofs – Benefits and cost implications
March 2004

Case Study 2
New Providence Wharf, Isle of Dogs, London

                                                                    D. Gedge
Type of development
Private housing development
Reason for Green Roof
Believed to be a planning condition for nature conservation [black redstarts]
Type of roof
Size of Green Roof
Build up of Roof
Flora drain fd25,
Filter sheet,
75mm extensive soil,
Sedums plug p7s
As this roof is inverted paving slabs would have had to be used if there was no
green element above the insulation. This would not have been that much
cheaper than a green roof.
Details of Green Roof Element
An extensive soil consisting of crushed recycled porous clay brick at 75mm
depth plug planted with sedums.

The green element should be installed by the end of March 2004. & Ecology Consultancy Ltd                                         41
Green Roofs – Benefits and cost implications
March 2004

Case Study 3

New Providence Wharf 2, Isle of Dogs, London

                                                                          D. Gedge
Type of development
Private housing development
Reason for Green Roof
Planning condition for reasons of nature conservation [black redstarts]
Type of roof
Single Ply
Size of Green Roof
Build up of Roof
Waterproofing – Hydrotech
50mm mineral soil
Sedum mat
Details of Green Roof Element
Sedum mat sits on mineral soil 50mm deep.
The green roof is being installed on the top of a 19 storey high block and
should be completed by the end of March 2004. & Ecology Consultancy Ltd                                            42
Green Roofs – Benefits and cost implications
March 2004

Case Study 4

Laban Dance Centre

                                                                       D. Gedge

                                                               D. Gedge/D. Brown

Type of development
Prestigious Dance Centre – the building won the 2003 Stirling Award for
Architecture see .

Reason for Green Roof
Planning condition for reasons of nature conservation

Type of roof

Size of Green Roof

Build up of Roof
These details are only for the green roof element as details of waterproofing
and insulation not available. & Ecology Consultancy Ltd                                          43
Green Roofs – Benefits and cost implications
March 2004

Insulation and Protection layer
Approximately 15cm of crushed rubble from site

Details of Green Roof Element

The green roof element consists of crushed demolition waste from the site
mixed and applied to the roof. This has been left to self colonise.

‘It is worth noting that we could have reduced costs further had the works
been better co-ordinated with the original roof installation. In particular, if we
had used the original mobile crane hire period to lift the material up to the roof
instead of hiring one specially,’
Rob Leslie-Carter, Project Manager Ove Arup, Laban Dance Centre

The roof was installed in the late summer 2002 and was the first of its kind. & Ecology Consultancy Ltd                                            44
Green Roofs – Benefits and cost implications
March 2004

Case Study 5

Chingford Pumping Station, Enfield, London

                                                                 Thames Water
Type of development
New Pumping Station facilities, 2 buildings to have green/brown roof
Reason for Green Roof
Added benefit for wildlife in a triple SSI area
Type of roof
Green/brown roof treatment
Size of Green Roof
Two roofs 626m2 in total area
Build up of Roof
Protection and moisture fleece
Crushed brick/concrete /subsoil growing medium
Details of Green Roof Element
The growing medium will vary in depth from 30mm –150mm

Client should get positive publicity when the roofs are complete and fits into
the company’s biodiversity action plan. The roofs are due to be built in 2004. & Ecology Consultancy Ltd                                        45
Green Roofs – Benefits and cost implications
March 2004

Case Study 6

Canary Wharf Estate, Isle of Dogs

                                                                       D. Gedge

Type of development
Office blocks

Reason for Green Roof
Canary Wharf wanted a green element to be viewed from main tower, 5
extensive green roofs and 3 intensive green roofs.

Type of roof
Inverted Roofs

Size of Green Roof
Between 5000 –6000m2

Build up of Roof
Building FC4/South Colonnade – Sedum mats on fleece
Retail – Sedum mats on 2cm gravel
Canada Place – Sedum mats on 75cm extensive crushed brick soil

The company has got publicity from the roofs. Planners, architects and other
professionals regularly visit the roofs. The first roof was constructed in 2000. & Ecology Consultancy Ltd                                          46
Green Roofs – Benefits and cost implications
March 2004

Case Study 7

St Martins in the Field School, Tulse Hill, London

Type of development
New Sports Hall

Reason for Green Roof
Building looks onto park. Visual amelioration as roof constructed of steel.

Type of roof
Curved steel framed acoustic standing seam aluminium roof

Size of Green Roof

Build up of Roof
Extensive soil
Two-thirds sedum plugs
One-third sedum mats

Details of Green Roof Element

As the roof is curved the lower area has had to be planted with sedum mats.
The rest is plug planted.

The client is very pleased with the roof. The green element is to be installed in
late March 2004. & Ecology Consultancy Ltd                                           47
Green Roofs – Benefits and cost implications
March 2004

Case Study 8

Mast Pond Quay, Woolwich, London

                                                       Nigel Upchurch Associates
Type of development
Private housing development

Reason for Green Roof
Provision of green roofs required to provide ecological mitigation in order to
secure Environment Agency necessary to achieve planning consent.

Type of roof

Size of Green Roof

Build up of Roof
Drainage layer, protection fleece, crushed aggregate sourced from the site
during demolition

Details of Green Roof Element
The material for the growing material has been collected from site and graded
in situ.
This development has just commenced and the roofs should be in place by
2005. & Ecology Consultancy Ltd                                          48
Green Roofs – Benefits and cost implications
March 2004

Case Study 9

Rolls Royce Factory, Chichester, West Sussex

Type of development

Reason for Green Roof
No direct contact with the company but is likely to be due to visual
amelioration. Also Rolls Royce is owned by BMW, which commonly uses
green roofs on its buildings in Germany. Believed to have a zero energy

Type of roof
Not known

Size of Green Roof
40,000m2 check

Build up of Roof
Extensive soil
Two-thirds sedum plugs
Hydro seeded

This is the largest block of green roofs in the country and was completed in
2003. & Ecology Consultancy Ltd                                      49
Green Roofs – Benefits and cost implications
March 2004

Case Study 10

Lillie Road, Fulham, London SW 6

                                                                   M. Frith
Type of development
Social housing [The Peabody Trust]

Reason for Green Roof
Contribution towards reducing surface water run-off

Type of roof
Probably single ply

Build up of Roof
Sedum mats

‘An example of high quality architectural design that is sensitive to its
surroundings and is environmentally sustainable, the design concept for
Peabody's new development in Lillie Road, Fulham, has won the RIBA
Housing Design Award 2001.

The Lillie Road scheme comprises 65 dwellings, including 14 key worker
homes, together with a mix of shared ownership and social housing, as well
as a community centre and car parking. Replacing a former school building,
which was demolished in 1998, the new homes are designed to be energy-
efficient. & Ecology Consultancy Ltd                                     50
Green Roofs – Benefits and cost implications
March 2004

This will be one of the first developments of its kind that will incorporate
structures that have been prefabricated off-site in modular form to incorporate
new technology and engineering techniques, whilst providing low energy
buildings with minimal end user costs.

As this scheme is adjacent to an existing Peabody housing project, which is
itself in a Conservation Area, the design for the new development had to be
sensitive to the local environment, both in terms of architectural style and use
of materials.’

The green roof was specifically designed to reduce rainwater run off. & Ecology Consultancy Ltd                                          51
Green Roofs – Benefits and cost implications
March 2004

Case Study 11

Wood Wharf, Isle of Dogs, London E14

                                                                British Waterways

Type of development
Multi use development scheme

Reason for Green Roof
Biodiversity is a key issue as black redstarts have bred on the current site for
a number of years. British Waterways, the owners of the site, are a partner in
the London Biodiversity Partnership and are aiming to meet objectives and
targets as laid out in the Partnership’s Black Redstart Action.

Wood Wharf is to be developed over the next 5 years and is only at the Master
Plan Stage and seeking investors. & Ecology Consultancy Ltd                                           52
Green Roofs – Benefits and cost implications
March 2004

Case Study 12

King’s Cross Regeneration Area, London, NW1

                                                           Argent St. George

Type of development
Multi use development scheme

Reason for Green Roof
The developers of King’s Cross Regeneration Area, Argent St. George are
constrained by London Borough of Camden to provide 15% green/brown roofs
for black redstarts and other nature conservation issues
The first specific planning application will include green roofs for black
redstarts & Ecology Consultancy Ltd                                      53
Green Roofs – Benefits and cost implications
March 2004

          Green roofs offer significant environmental benefits in terms of
          sustainable development in urban regeneration schemes. Although the
          initial costs of installation are higher than more conventional systems,
          green roofs are economic in the long term over a 25-year period. As the
          case studies show they can be used on various types of buildings with
          differing uses. In fact many of the owners/developers contacted, though
          they had real concerns at the early stages, commented that the
          installation of the green roofs had been positive for a number of
          reasons, whether it was aesthetic, prestige, or protection of vulnerable
          roofing membranes during construction.

          Experience elsewhere in the country has shown that, although there is
          a policy vacuum at present, local initiatives have proved effective in
          getting green roofs installed, especially in terms of biodiversity
          conservation. This is also an issue in Birmingham and could provide
          the lever to encourage developers to consider the use of green roofs in
          new design and build operations.

          Green roofs have a real and effective role to play in sustainable
          development in both urban and rural situations, not merely for the
          benefits outlined above, but also as a catalyst for changing mindsets on
          how new buildings should be designed. By creating functional green
          space on buildings, green roofs, whether that function is for
          biodiversity, storm water attenuation or public amenity, can provide a
          catalyst for a healthy and sustainable Eastside. To do this all agencies
          and statutory bodies need to act in concord to ensure that developers
          are encouraged or, if need be, constrained to embrace this growing
          technology in their schemes. & Ecology Consultancy Ltd                                            54
Green Roofs – Benefits and cost implications
March 2004


          •    Experience elsewhere in the country has demonstrated the need for
               developers and their architects to actually see differing green roof
               systems. It is therefore recommended that an exhibition roof is
               located, which can hold a number of ‘samples’ of different types of
               green roofs.
          •    The installation of a full green roof in the Eastside Area on a new
               build as soon as possible to provide impetus within the regeneration
               area and elsewhere in Birmingham for green roofs on new
          •    Further research should be commissioned into what and how green
               roofs can meet Birmingham City Council’s Targets for Carbon
               Dioxide Reduction, Secondary Aggregate Re use and other relevant
          •    Gather baseline data on typical buildings in Birmingham that are
               representative of the type of new developments likely to happen in
               the Eastside area.
          •    Produce a Vision Statement on Green Roofs in Eastside and ensure
               that they are included in any master plans.
          •    Produce a Green Roof Guide for developers setting out the different
               types of green roofs, costs and Birmingham Eastside’s aspirations
               in terms of sustainable targets. & Ecology Consultancy Ltd                                             55
Green Roofs – Benefits and cost implications
March 2004


          This report would not have been written without the help and
          commitment of Jill Goddard and other members of the Creekside
          Ecology Team, Stephan Brenneisen, G.Kadas, James Farrell, Pete
          Massini, the London Wildlife Trust and others in the London
          Biodiversity Partnership.

          The authors are indebted to a number of professionals involved in
          Green Roofs, particularly Peter Allnutt and Alun Rhys Tarr but also Nick
          Ridout, Mike Jones, Mark Harris, Alan Roofing, Performance Deck and
          Fenland Roofing. & Ecology Consultancy Ltd                                            56
Green Roofs – Benefits and cost implications
March 2004


National Planning Policies
Planning Policy Guidance 1: General policy and principles
This, the umbrella guidance for the Government’s planning policies,
establishes the principles and context for planning in England. The following
are of interest:

Introduction                             1. A key role of the planning system is to enable the provision of homes
                                         and buildings, investment and jobs in a way which is consistent with the
                                         principles of sustainable development. It needs to be positive in
                                         promoting competitiveness while being protective towards the
                                         environment and amenity.
Sustainable development                  4. Sustainable development seeks to deliver the objective of achieving,
                                         now and in the future, economic development to secure higher living
                                         standards while protecting and enhancing the environment. The
                                         Government is committed to the principles of sustainable development
                                         set out in Sustainable Development: The UK Strategy (1994).
                                         7. Urban regeneration and re-use of previously-developed land are
                                         important supporting objectives for creating a more sustainable pattern
                                         of development. The Government is committed to:
                                          •     concentrating development for uses which generate a large
                                                number of trips in places well-served by public transport,
                                                especially town centres, rather than in out-of-centre locations; and
                                          •     preferring the development of land within urban areas, particularly
                                                on previously-developed sites, provided that this creates or
                                                maintains a good living environment, before considering the
                                                development of greenfield sites.
Design                                   14. For the purposes of this Guidance, urban design should be taken to
                                         mean the complex relationships between all the elements of built and
                                         un-built space. As the appearance and treatment of the spaces
                                         between and around buildings is often of comparable importance to the
                                         design of the buildings themselves, landscape design should be
                                         considered as an integral part of urban design.
                                         19. Design policies and guidance should focus on encouraging good
                                         design and should avoid stifling responsible innovation, originality or
                                         initiative. Such policies and guidance should recognise that the qualities
                                         of an outstanding scheme may exceptionally justify departing from
                                         them. & Ecology Consultancy Ltd                                                                57
Green Roofs – Benefits and cost implications
March 2004

Planning Policy Guidance 3: Housing (2000)

Creating Sustainable                     46. To promote more sustainable residential environments, both within
Residential Environments                 and outside existing urban areas, local planning authorities should
                                          • a greener residential environment;
                                          • greater emphasis on quality and designing places for people; and
                                          • the most efficient use of land.
Greening the residential                 52. The Government attaches particular importance to the 'greening' of
environment                              residential environments. Greening initiatives can enhance quality,
                                         assist the permeability of land for storm drainage and contribute to bio-
                                         diversity. Well designed layouts can also contribute to the energy
                                         efficiency of new housing. Landscaping should be an integral part of
                                         new development and opportunities should be taken for the retention of
                                         existing trees and shrubs, and for new plantings.
                                         53. Local planning authorities should have clear policies for the
                                         protection and creation of open space and playing fields, and new
                                         housing developments should incorporate sufficient provision where
                                         such spaces are not already adequately provided within easy access of
                                         the new housing. Developing more housing within urban areas should
                                         not mean building on urban green spaces.
Designing for quality                    54. Good design and layout of new development can help to achieve
                                         the Government's objectives of making the best use of previously-
                                         developed land and improving the quality and attractiveness of
                                         residential areas. Local planning authorities and developers should
                                         think imaginatively about designs and layouts which make more
                                         efficient use of land without compromising the quality of the
                                         56. New housing development of whatever scale should not be viewed
                                         in isolation. Considerations of design and layout must be informed by
                                         the wider context [including] the townscape and landscape of the wider
                                         locality. The local pattern of streets and spaces, building traditions,
                                         materials and ecology should all help to determine the character and
                                         identity of a development, recognising that new building technologies
                                         are capable of delivering acceptable built forms and may be more
                                         efficient. Local planning authorities should adopt policies which:
                                          •     create places and spaces with the needs of people in mind, which
                                                are attractive, have their own distinctive identity but respect and
                                                enhance local character; and
                                          • promote the energy efficiency of new housing where possible.

Better places to live by design: a companion guide to PPG3 (2001)

Chapter 6 Space             in   and     External space to the rear requires similar analysis whether this is
around the home                          private, communal or a mix of both. At ground level, the best solutions
Relating indoor and outdoor              will provide a sharing of space, from the garden into the house and from
space                                    the house into the garden, allowing for a different patterns of living
                                         during the summer and winter months. Above this, the potential for
                                         balconies and roof gardens, both projected and recessed, should be
                                         explored. A key consideration is that balconies should be useable and
                                         not merely decorative. This raises specific issues, not only about size
                                         but also involves thinking about orientation, views, the circulation
                                         patterns of the internal space, massing forms such as stepped
                                         structures as well as construction methods. & Ecology Consultancy Ltd                                                               58
Green Roofs – Benefits and cost implications
March 2004

Planning Policy Guidance 9: Nature conservation (1994)

Introduction                             1 The wildlife of Britain is an integral part of its countryside, towns and
                                         2 The Government's objectives for nature conservation are to ensure
                                         that its policies contribute to the conservation of the abundance and
                                         diversity of British wildlife and its habitats, or minimise the adverse
                                         effects on wildlife where conflict of interest is unavoidable, and to meet
                                         its international responsibilities and obligations for nature conservation.
                                         3 One of the essential tasks for Government, local authorities, and all
                                         public agencies concerned with the use of land and natural resources is
                                         to make adequate provision for development and economic growth
                                         whilst ensuring effective conservation of wildlife and natural features as
                                         an important element of a clean and healthy natural environment. The
                                         conservation of nature is important. Attractive environments, where
                                         attention is given to nature conservation, are essential to social and
                                         economic well-being. With careful planning and control, conservation
                                         and development can be compatible.
Statutory Framework                      7 Successive Governments since 1949 have built up and applied a
                                         framework of statutory measures to safeguard the natural heritage. This
                                         consists of both conservation and planning legislation and has been
                                         strengthened significantly in recent years [including]:
                                         The Wildlife and Countryside Act 1981 strengthened the protection for
                                         SSSIs, provided additional safeguards for particular types of area, and
                                         restricted the killing, taking from the wild and disturbance of various
Nature Conservation                      14 Our natural wildlife heritage is not confined to the various statutorily
Outside Designated Sites                 designated sites but is found… in many urban and coastal areas. Many
                                         urban sites for nature conservation have an enhanced local importance
                                         as a consequence of the relative lack of wildlife sites in built-up areas.
                                         Endangered species protected under the 1981 Act may be found in
                                         many places not notified as SSSIs.
                                         15 Many sites of local nature conservation importance are given
                                         designations by local authorities and by local conservation
                                         organisations. These sites are important to local communities, often
                                         affording people the only opportunity of direct contact with nature,
                                         especially in urban areas. Statutory and non-statutory sites, together
                                         with countryside features which provide wildlife corridors, links or
                                         stepping stones from one habitat to another, all help to form a network
                                         necessary to ensure the maintenance of the current range and diversity
                                         of our flora, fauna, and the survival of important species. Sensitive
                                         landscaping and planting, the creation, maintenance and management
                                         of landscape features important to wildlife, and the skilled adaptation of
                                         derelict areas can provide extended habitats.
                                         18 Local planning authorities should have regard to the relative
                                         significance of international, national, local and informal designations in
                                         considering the weight to be attached to nature conservation interests.
                                         They should only apply local designations to sites of substantive nature
                                         conservation value, and take care to avoid unnecessary constraints on
Nature Conservation and land             19 The Government's general policy on nature conservation is outlined
Use Planning                             in the introduction. Nature conservation objectives should be taken into
                                         account in all planning activities… in urban areas where there is wildlife
                                         of local importance. They should be reflected in regional planning
                                         guidance, structure plans, unitary development plans and local plans.
Regional and strategic                   21 Nature conservation issues are not confined by administrative
planning guidance                        boundaries, and should be addressed on a strategic basis. Regional
                                         planning guidance notes issued by the [ODPM] include nature
                                         conservation issues but the form of that guidance means that the issue
                                         is addressed very generally. Local authorities should aim to ensure that & Ecology Consultancy Ltd                                                                59
Green Roofs – Benefits and cost implications
March 2004

                                         regional nature conservation issues are brought before the regional
                                         planning conferences.
Protection of Species                    44 Part 1 of the Wildlife and Countryside Act 1981 sets out the
                                         protection which is afforded to wild animals and plants. Every five years,
                                         the Schedules to the Act relating to protected animals (Schedule 5) and
                                         plants (Schedule 8) are reviewed. Local authorities are notified of any
                                         amendments and additions to those Schedules as a result of the review
                                         and are bound by the Act to take steps to bring to the attention of the
                                         public… the provisions of Part 1 of the Act. The protection offered by the
                                         Act is additional to that offered by the planning system.
                                         45 Certain plant and animal species, including all wild birds, are
                                         protected under the 1981 Act. Some other animals are protected under
                                         their own legislation. It is an offence to ill-treat any animal; to kill, injure,
                                         sell or take protected species (with certain exceptions); or intentionally
                                         to damage, destroy or obstruct their places of shelter. Bats enjoy
                                         additional protection. It is an offence to kill, injure or disturb bats found
                                         in the non-living areas of a dwelling house (that is, in the loft) or in any
                                         other place without first notifying English Nature.
                                         46 The Conservation (Natural Habitats,&c.) Regulations 1994 (the
                                         Habitats Regulations) implement the requirements of the Habitats
                                         Directive for species listed in Annex IV of the Directive (see Annex G to
                                         this PPG). It is an offence deliberately to kill, injure, take or disturb listed
                                         animal species; to destroy their resting places or breeding sites; or to
                                         pick, collect, cut, uproot or otherwise destroy listed plant species.
                                         47 The presence of a protected species is a material consideration
                                         when a local planning authority is considering a development proposal
                                         which, if carried out, would be likely to result in harm to the species or
                                         its habitat. Local authorities should consult English Nature before
                                         granting planning permission. They should consider attaching
                                         appropriate planning conditions or entering into planning obligations
                                         under which the developer would take steps to secure the protection of
                                         the species, particularly if a species listed in Annex IV to the Habitats
                                         Directive would be affected. They should also advise developers that
                                         they must conform with any statutory species protection provisions
                                         affecting the site concerned. & Ecology Consultancy Ltd                                                                     60
Green Roofs – Benefits and cost implications
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Planning Policy Guidance Note 11; Regional Planning Guidance
10. Biodiversity And Nature              10.1 Biodiversity means the variety of life, among both plants and
Conservation                             animals. Government policies aim to conserve and enhance this
                                         variety. Their success will be a key test of sustainable development.
                                         The Government has set out its general policy in the UK Biodiversity
                                         Action Plan (1994) and it has also broadly endorsed the approach of
                                         the UK Biodiversity Steering Group report (1995). Central to this is the
                                         preparation and implementation of costed action plans for priority
                                         species and habitats. Although these action plans are the key
                                         implementation mechanism, RPG has a role in conserving the existing
                                         wildlife resource and in providing guidance on how structure plans and
                                         Part I UDPs should seek to mitigate adverse effects, foster biodiversity
                                         and protect ecosystems both in rural and urban areas. Advice on how
                                         nature conservation should be taken into account in planning policies
                                         and decisions is set out in PPG9.
                                         10.2 In order for RPG to fulfil these objectives and complement any
                                         regional biodiversity strategies, RPBs should liaise closely with regional
                                         biodiversity for a or equivalent bodies, English Nature and the
                                         Environment Agency, and also with bodies working on sub-regional
                                         initiatives such as management schemes for European marine sites
                                         and integrated plans for coastal zone management. In drawing up the
                                         spatial strategy in RPG it will be important to identify and take account
                                         of the regional distribution and sub-regional concentrations of priority
                                         habitats and species, and the internationally or nationally designated
                                         areas referred to above, to inform the regional spatial strategy. In doing
                                         so the RPB should consider how the distribution of these nationally or
                                         regionally significant species and habitats may change as a result of
                                         climate change. RPG should:
                                         • incorporate biodiversity and nature conservation objectives into
                                                regional development objectives;
                                         • conserve and promote biodiversity at the regional and sub-regional
                                                level including by flagging up the potential for enhancing
                                         • establish regional targets, where appropriate, for community forest
                                                cover and creation of strategic green open spaces in the urban
14. Energy                               14.1 There are two main energy dimensions to RPG; reducing demand
                                         for energy and facilitating the provision of renewable energy.
                                         Regional dimension to energy efficiency
                                         14.2 Energy efficiency underpins a number of Government policies and
                                         initiatives, both environmental and social, such as the reduction of CO2
                                         emissions and fuel poverty. An energy efficient pattern of development
                                         and energy efficient buildings will form an essential part of the UK's
                                         response to international climate change agreements and to
                                         sustainable development strategies. Therefore, RPG should promote
                                         energy efficiency both in the pattern of development proposed in the
                                         spatial development strategy and in the more general advice it may set
                                         out for the preparation of development plans. & Ecology Consultancy Ltd                                                               61
Green Roofs – Benefits and cost implications
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Planning Policy Guidance 17: Planning for open space, sport and
recreation (2002)

These predominantly relate to existing and potential terrestrial open spaces.
However, innovative approaches could feasibly demonstrate the creation of
accessible green roofs could meet policy objectives. The following are the
most pertinent policy statements. The accompanying guide gives details of
how to audit and assess open space requirements and provision in urban
areas; it too has little of direct relevance, but similar principles apply.

Planning Objectives                      Open spaces, sport and recreation all underpin people's quality of life.
                                         Well designed and implemented planning policies for open space, sport
                                         and recreation are therefore fundamental to delivering broader
                                         Government objectives. These include:
                                         • supporting an urban renaissance - local networks of high quality and
                                            well managed and maintained open spaces… help create urban
                                            environments that are attractive, clean and safe. Green spaces in
                                            urban areas perform vital functions as areas for nature conservation
                                            and biodiversity and by acting as 'green lungs' can assist in meeting
                                            objectives to improve air quality.
                                         • promotion of social inclusion and community cohesion - well
                                            planned and maintained open spaces… can play a major part in
                                            improving people's sense of well being in the place they live.
                                         • health and well being - open spaces, sports and recreational
                                            facilities have a vital role to play in promoting healthy living and
                                            preventing illness, and in the social development of children of all
                                         • promoting more sustainable development - by ensuring that open
                                            space (particularly in urban areas) are easily accessible.
Planning For New Open                    General principles
Space And Sports And                     20. In identifying where to locate new areas of open space, sports and
Recreational Facilities                  recreational facilities, local authorities should:
                                              iii. avoid any significant loss of amenity to residents, neighbouring
                                              uses or biodiversity;
                                              iv. improve the quality of the public realm through good design;
                                              v. look to provide areas of open space in commercial and industrial
                                              vi. add to and enhance the range and quality of existing facilities;
                                              viii. meet the regeneration needs of areas, using brownfield in
                                              preference to greenfield sites;
                                              xi. consider the recreational needs of visitors and tourists.
                                         In addition to these general principles, paragraphs 21 - 32 below apply
                                         in respect of specific types of facilities or areas.
                                         Open Spaces
                                         24. In planning for new open spaces and in assessing planning
                                         applications for development, local authorities should seek
                                         opportunities to improve the local open space network, to create public
                                         open space from vacant land, and to incorporate open space within new
                                         development on previously-used land. They should also consider
                                         whether use can be made of land which is otherwise unsuitable for
                                         development, or procure public use of privately owned areas of land or
                                         sports facilities. & Ecology Consultancy Ltd                                                                62
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Assessing needs and opportunities: Planning Policy Guidance 17 companion
guide (2002)

Chapter 8 - Step 5: Drafting             New Provision
Policies                                 8.8 The main opportunities for new provision are likely to include:
Identifying Strategic                     • Areas where comprehensive redevelopment may be proposed,
Options                                      such as run-down former Council housing estates
Identifying Opportunities For             • Derelict land or brownfield land unsuitable for development, for
New, Enhanced Or Relocated                   which open space or sport and recreation provision may be a cost-
Provision                                    effective new use, depending on location and local needs.
                                             However, authorities should not provide important community
                                             facilities on land liable to flooding. Even in areas where there is no
                                             deficiency in provision, converting land unsuitable for development
                                             into open space, and then redeveloping an existing open space
                                             may be a sensible policy option. Such land swaps are allowed by
                                             paragraph 13 of PPG17 and can result in better overall use of land,
                                             significant environmental improvements and higher amenity,
                                             provided the new provision will be at least as accessible to users. & Ecology Consultancy Ltd                                                                63
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Planning Policy Guidance 24: Planning and noise

This directly addresses the policy requirements in respect of noise-creating
development (e.g. industry), rather than how noise reduction can be built into
new development per se.
Development control                      12. Local planning authorities should consider carefully in each case
Noise-sensitive                          whether proposals for new noise-sensitive development would be
development                              incompatible with existing activities. Such development should not
                                         normally be permitted in areas which are - or are expected to become -
                                         subject to unacceptably high levels of noise. When determining
                                         planning applications for development which will be exposed to an
                                         existing noise source, local planning authorities should consider both
                                         the likely level of noise exposure at the time of the application and any
                                         increase that may reasonably be expected in the foreseeable future, for
                                         example at an airport.
Measures to mitigate the                 13. A number of measures can be introduced to control the source of, or
impact of noise                          limit exposure to, noise. Such measures should be proportionate and
                                         reasonable and may include one or more of the following:
                                            I. engineering: reduction of noise at point of generation;
                                                containment of noise generated (eg by insulating buildings
                                                which house machinery and/or providing purpose-built barriers
                                                around the site); and protection of surrounding noise-sensitive
                                                buildings (eg by improving sound insulation in these buildings
                                                and/or screening them by purpose-built barriers);
                                            II. lay-out: adequate distance between source and noise-
                                                sensitive building or area; screening by natural barriers, other
                                                buildings, or non-critical rooms in a building; & Ecology Consultancy Ltd                                                              64
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Planning Policy Guidance 25: Development and flood risk
Flooding And Land-Use                    22. In particular, as part of its strategy for sustainable development, the
Planning - General                       Government wishes to avoid an unnecessary increase in the
Considerations                           requirement to provide artificial defence against flooding. Local
                                         planning authorities should, therefore, consider the information
                                         available on the nature of flood risk and its potential consequences and
                                         accord it appropriate weight in the preparation of development plans
                                         and in determining applications for planning permission and attaching
                                         conditions where permission is granted. They should apply the
                                         sequential approach in paragraph 30 and Table 1 to their plan-making
                                         and development control functions.

                                         35. The Government places great emphasis on the need for urban
                                         regeneration and the redevelopment of previously developed land to
                                         minimise the need for development of green-field land. Because much
                                         past industrial development took place alongside rivers on suitable flat
                                         land, some previously developed land will be vulnerable to flooding. In
                                         making proposals for redevelopment of such land or the re-use of
                                         existing buildings and structures, local authorities should take account
                                         of the risks of flooding, the standards of existing flood defences and the
                                         ability to improve them. Any such redevelopment should avoid
                                         interference with flood plain flows or compromising future shoreline or
                                         river management options. Developers and local planning authorities
                                         should consider what types of new development would be appropriate
                                         to these circumstances. For example, a site may not be sufficiently well
                                         defended to make it suitable for housing over its full area, although it
                                         might still be possible to incorporate housing within a mixed-use
                                         scheme, utilising parts of a site at higher risk of flooding for open space
                                         or other recreational provision. Similarly, the upper levels of converted
                                         structures, eg in former port or warehouse areas, might be appropriate
                                         for housing with public areas and other uses at a lower level. A
                                         balanced flexible approach is required which addresses the risks of
                                         flooding whilst recognising the benefits of recycling previously
                                         developed land and the damage to urban regeneration caused by
                                         under-investment and urban blight. The acknowledged risks of flooding
                                         might be mitigated by confirmed good levels of protection, including
                                         protected access, prudent design of development and effective public
                                         warning mechanisms. Sites vulnerable to rapid inundation should
                                         defences be overtopped or breached are unlikely to be suitable for
                                         those of restricted mobility, whether in conventional, adapted or
                                         sheltered housing or in institutional accommodation.
                                         36. Planning guidance on housing (PPG 3) already advises local
                                         planning authorities to take account of physical and environmental
                                         constraints on the development of land for housing, including flood risk.
                                         The principles in this guidance complement that advice. PPG 3 requires
                                         priority to be given to re-using previously developed land within urban
                                         areas, bringing empty homes back into use and converting existing
                                         buildings in preference to the development of green-field sites. Nothing
                                         in PPG 25 should be taken as departing from this guidance.
Canals and other artificial              38. The implications for development are twofold. Firstly, since the
water bodies                             concept of a flood plain is not applicable, waterside development or
                                         redevelopment of previously developed land may not face the same
                                         flood-risk constraints as development alongside a river. Canals may
                                         thus retain their potential to act as catalysts for urban and rural
                                         regeneration. Secondly, where developments propose to drain into a
                                         canal, due consideration should be given to the level and impact this
                                         drainage would have on the canals ability to store water. The use of
                                         sustainable drainage systems is one way of overcoming concerns
                                         about the impact of development on the canals ability to handle flood
                                         water. However, authorities considering development in the vicinity of & Ecology Consultancy Ltd                                                                65
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                                         canals should not overlook their own capacity to cause localised
                                         flooding, eg where overflow channels fail to operate or where canal
                                         embankments fail or are breached. Dams and reservoirs pose a similar
                                         potential for possibly large-scale flooding. As for river flooding, a
                                         precautionary approach should be adopted at vulnerable locations,
                                         after consultation with the canal operator or dam/reservoir owner.
Appendix E                               E4. Sustainable drainage systems use techniques to control surface
What are sustainable                     water run-off as close to its origin as possible, before it enters a
drainage systems?                        watercourse. This involves moving away from traditional piped drainage
                                         systems to engineering solutions that mimic natural drainage
                                         E5. A wide range of sustainable drainage options is available, from
                                         which promoters, designers, developers, planners, drainage specialists
                                         and civil engineers may choose in preference to piped drainage
                                         systems, including:
                                          •    preventive measures -- eg rain-water recycling, good-practice
                                               design and maintenance;
                                          •    filter strips and swales vegetated landscape features with smooth
                                               surfaces and a gentle downhill gradient to drain water evenly off
                                               impermeable surfaces, mimicking natural drainage patterns;
                                          •    filter drains and permeable and porous pavements permeable
                                               surfaces to allow rainwater and run-off to infiltrate into permeable
                                               material placed below ground to store water prior to discharge;
                                          •    infiltration devices -- below-ground or surface structures to drain
                                               water directly into the ground (soakaways, infiltration trenches,
                                               swales with infiltration and infiltration basins), which may be used
                                               at source or the run-off may be conveyed to the infiltration area in
                                               a pipe or swale; and
                                          •    basins and ponds structures designed to hold water when it rains;
                                               basins are free from water in dry weather, ponds contain water at
                                               all times and are designed to hold more when it rains; examples
                                               include detention basins, balancing/attenuation ponds, flood
                                               storage reservoirs, lagoons, retention ponds and wetlands/reed
                                         E6. Local planning authorities and developers should seek advice from
                                         the Environment Agency, highways authorities and sewerage
                                         undertakers on the techniques available for sustainable drainage and
                                         their suitability for proposed development or redevelopment in specific
Benefits of and constraints              E7. Sustainable drainage systems can help reduce the environmental
on sustainable drainage                  impact of development. Their use provides a significant contribution
systems                                  towards more sustainable development since they:
                                          •    manage environmental impacts at source, rather than
                                          •    manage water run-off rates, reducing the impact of urbanisation on
                                          •    protect or enhance water quality;
                                          •    are sympathetic to the environmental setting and the needs of the
                                               local community;
                                          •    provide opportunities to create habitats for wildlife in urban
                                               watercourses; and
                                          •    can encourage natural groundwater recharge (where appropriate).
                                         E8. Although the benefits of sustainable drainage systems are secured
                                         principally at the river-catchment scale, their early consideration at all
                                         levels of the planning and development process can lead to
                                         opportunities for more imaginative and attractive developments.
                                         Surface water management using sustainable drainage systems can be
                                         implemented at all scales. It may start with prevention or good
                                         housekeeping measures and soakaways for individual premises and
                                         progress through the use of infiltration devices, tank storage or small & Ecology Consultancy Ltd                                                               66
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                                         basins for larger sites to basins and wetlands at the sub-regional scale.
                                         At any level, it can help to reduce the need for investment in flood
                                         management and protection works by mitigating the intrinsic additional
                                         flood risk that new development might otherwise generate. The use of
                                         sustainable drainage systems can in some circumstances allow
                                         development to proceed that would otherwise be refused because of
                                         the increased flood risk caused by run-off.
                                         E9. While there are clear benefits to the use of sustainable drainage
                                         systems, there are also some constraints on the choice of system. The
                                         surface structures that may be needed can take more space than
                                         conventional systems. It is often possible, however, for them to be
                                         integrated into the surrounding land use, eg in public open space or
                                         road verges. & Ecology Consultancy Ltd                                                              67
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The London Plan (2004)

The Spatial Development Strategy for London has reflected the emerging
interest in green roofs by their specific mention and inferred reference in a
couple of policy supporting paragraphs. The Supplementary Planning
Guidance on Sustainable Design & Construction is at draft stage and
expected for public consultation during early 2004.

Policy 4B.6 Sustainable                  The Mayor will, and boroughs should, ensure future developments meet
design and construction                  the highest standards of sustainable design and construction and reflect
                                         this principle in UDP policies.
                                         These will include measures to:
                                          •    re-use land and buildings
                                          •    conserve energy, materials, water and other resources
                                          •    ensure designs make the most of natural systems both within and
                                               around the building
                                          •    reduce the impacts of noise, pollution, flooding and micro-climatic
                                          •    ensure developments are comfortable and secure for users
                                          •    conserve and enhance the natural environment, particularly in
                                               relation to biodiversity
                                          •    promote sustainable waste behaviour in new and existing
                                               developments, including support for local integrated recycling
                                               schemes, CHP schemes and other treatment options (subject to
                                               Policy 4A.1 and 4A.2).
                                          •    Applications for strategic developments should include a
                                               statement showing how sustainability principles will be met in
                                               terms of demolition, construction and long-term management.
                                          •    Boroughs should ensure that, where appropriate, the same
                                               sustainability principles are used to assess planning applications.
                                         4.52 Sustainable design and construction can reduce the consumption
                                         of resources, cut greenhouse gases and contribute to the good health
                                         of Londoners. Sustainable design is based on principles that are
                                         intended to ensure that buildings are efficient in resource use,
                                         recognise the uniqueness of locations, are healthy, adaptable and
                                         responsible in
                                         protecting the environment and make the most of natural systems
                                         including, for example the use of passive solar design or local
                                         ecosystems. Several of these issues are addressed through Building
                                         Regulation requirements and other procedures. This policy should sit
                                         alongside those requirements. The Mayor will work with partners to
                                         produce Supplementary Planning Guidance and to provide further
                                         information on relevant aspirational targets.
Policy 4B.9 Large-scale                  All large-scale buildings including tall buildings should be of the highest
buildings – design and                   quality design and in particular:
impact                                    •    meet the requirements of the View Protection Framework set out
                                               in Policy 4B.15 of this plan
                                          •    be suited to their wider context in terms of proportion and
                                               composition and in terms of their relationship to other buildings,
                                               streets, public and private open spaces, the waterways or other
                                               townscape elements
                                          •    illustrate exemplary standards of sustainable construction and
                                               resource management and potential for renewable energy
                                               generation and recycling
                                          •    be sensitive to their impact on micro-climates in terms of wind,
                                               sun, reflection and overshadowing
                                          •    pay particular attention, in residential environments, to privacy,
                                               amenity and overshadowing & Ecology Consultancy Ltd                                                                68
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Policy 3D.12 Biodiversity and            The Mayor will work with partners to ensure a proactive approach to the
nature conservation                      protection, promotion and management of biodiversity in support of the
                                         Mayor’s Biodiversity Strategy.

                                         The planning of new development and regeneration should have regard
                                         to nature conservation and biodiversity, and opportunities should be
                                         taken to achieve positive gains for conservation through the form and
                                         design of development. Where appropriate, measures may include
                                         creating, enhancing and managing wildlife habitat and natural
                                         landscape. Priority for habitat creation should be given to sites which
                                         assist in achieving the targets in Biodiversity Action Plans (BAPs) and
                                         sites within or near to areas deficient in accessible wildlife sites.
                                         Boroughs, in reviewing UDPs and in considering proposals for
                                         development should accord the highest protection to internationally
                                         designated and proposed sites (SACs, SPAs and Ramsar sites), and to
                                         nationally designated sites (SSSIs) in accordance with government
                                         guidance and the Habitat Regulations, 1994.
                                         Where development is proposed which would affect a site of importance
                                         for nature conservation, the approach should be to seek to avoid
                                         adverse impact on the nature conservation value of the site, and if that
                                         is not possible, to minimise such impact and seek mitigation of any
                                         residual impacts. Where, exceptionally, development is to be permitted
                                         because the reasons for it are judged to outweigh significant harm to
                                         nature conservation, appropriate compensation should be sought.
                                         3.258 The Mayor expects the biodiversity and natural heritage of
                                         London to be conserved and enhanced for the benefit of this and future
                                         generations. He will assist boroughs in doing this with advice on UDP
                                         policies for biodiversity. Planning applications should give full
                                         consideration to the effects, both direct and indirect, of development
                                         upon biodiversity, wildlife habitat and geology. Indirect effects include
                                         increased use and disturbance, hydrological changes, level of noise,
                                         pollution, shading and lighting disturbance. In Policy 3D.12,
                                         compensation is used in the context of reducing and off-setting the
                                         harm caused by development and involves the provision of features to
                                         replace those lost as a result, preferably by like with like. Because most
                                         wildlife habitats are difficult to recreate, the replacement or relocation of
                                         species and habitat should be considered only as a last resort.
                                         3.260 One of the key objectives of the Mayor’s Biodiversity Strategy is
                                         to ensure that all Londoners have ready access to wildlife and natural
                                         green spaces. This is particularly important where there is a shortage of
                                         green space and in Areas for Regeneration. Access can be improved
                                         by making places more attractive and safer, enhancing or creating new
                                         wildlife habitats and opening up access to existing habitats. Wherever
                                         appropriate, new development should include new or enhanced habitat,
                                         or design (such as green roofs) and landscaping that promotes
                                         biodiversity, and provision for their management. & Ecology Consultancy Ltd                                                                 69
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Regional Planning Policies
West Midlands Regional Planning Guidance

The Draft Regional Planning Guidance (RPG) for the West Midlands was
published in 2001, and once approved by the Secretary of State, will replace
the existing RPG (RPG11) of 1998.

The review represents a shift in policy towards sustainability; the principles of
sustainable development now ‘lie at the heart of the Spatial Strategy for the
Region.’ This is spelt outlined in Chapter 2, and spelt out in more detail in
Chapter 8.

The Regional Vision                  Policy SD1
                                     All strategies, plans and programmes of local authorities and
                                     other agencies within the Region should adopt the
                                     Government’s broad objectives for sustainable development
                                     Maintenance of high and stable levels of economic growth and
                                     Social progress which recognises the needs of everyone;
                                     Effective protection and enhancement of the environment; and
                                     Prudent use of natural resources.

Chapter 8, Quality of the Environment, sets out a range of policies that serve
to regard the region’s environment as a major asset, which can support wider
economic and social aspirations, and serve to act as a ‘key component in

Environmental Capital                 Policy QE1
                                      Sustainable development should lead to the enhancement of
                                      the Region’s environmental capital. To ensure a net gain and
                                      to avoid significant losses to any aspect, all local authorities
                                      should identify and evaluate the environmental capital of their
                                      area according to an appropriate appraisal. This should inform
                                      the preparation or review of development plans, other
                                      strategies and development control processes by [including]: b:
                                      helping to identify opportunities to restore degraded areas and
                                      create new environments;
                                      8.14 The wider environment, made up of the natural, built and
                                      historic components, defines the character of an area vital to
                                      the attraction of future investment. Degraded areas depict a
                                      poor image and regeneration will only occur if people and
                                      businesses want to work and live there. Creating new high
                                      quality environments and a positive sense of place must
                                      therefore be a vital component of wider strategies for urban
                                      8.15 Sites in most need of regeneration are often in locations
                                      suffering the worst environments with poor air quality, high
                                      noise pollution, contaminated land and poor visual aesthetics. & Ecology Consultancy Ltd                                                                70
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                                      Policy QE2
                                      Local Authorities, other agencies and local communities should
                                      work together to develop strategies and programmes that
                                      optimise the contribution that the natural, built and historic
                                      environment can make to physical, economic and social
                                      regeneraion of the West Midlands. Regeneration schemes
                                      should capitalise on the quality and distinctiveness of the
                                      Region’s urban and rural environment. Development Plans
                                      and other strategies should [include]:
                                      contain policies that promote environmental improvements as a
                                      means of regenerating areas of social, economic and
                                      environmental deprivation;
                                      promote the restoration… and reuse of buildings. Particular
                                      emphasis should be given to sites which promote urban
                                      regeneration, reduce sources of pollution, renumerate against
                                      environmental impacts, and where they will not adversely
                                      impact upon existing habitats [or] species of recognised
                                      Promote, where appropriate… wildlife habitat creation asa
                                      component of the restoration of… former industrial land,
                                      particularly where it contributes to Local Biodiversity Action
                                      Plan targets.
Creating a high quality built         8.17 Good design can potentially play a key role in… urban
environment for all                   renaissance… it can contrinute to creating high quality
                                      environments where more people want to live, work and invest.
                                      More specifically flagship projects can often change the inage
                                      of an ara with new high quality buildings acting as symbos of
                                      renewed confidence.
                                      Policy QE3
                                      Development Plans and other strategies should promote the
                                      creation of high quality built environments as par of urban and
                                      rural renaissance and the regeneration strategies for the
                                      Region’s cities, towns and villages. Particular attention should
                                      be given to [including]:
                                      Securing a high quality townscape, urban form, building design
                                      and urban spaces, through the use of architecture, urban
                                      design and landscape design, which respects regional and
                                      local character;
                                      Creating and enhancing urban green space networks;
                                      d. Incorporating sustainability considerations such as energy
                                      and water efficiency, sustainable construction and drainage,
                                      building orientation, use of recycled materials, minimisation of
                                      waste, construction materials and maximising the lifespan of
                                      the building.
Protecting, managing and              8.41 Conservation of biodiversity is a key component of
enhancing the Region’s                sustainable development and contributes to our quality of life.
biodiversity and nature               [Its benefits] must be recognised, not viewed as constraints,
conservation resources                and secured by development. All the Region’s development
                                      needs can be accommodated without competing with the tiny
                                      area covered by key biodiversity sites. & Ecology Consultancy Ltd                                                                71
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                                      Policy QE6
                                      All the pans and programmes of local authorities and other
                                      relevant agencies in the West Midlands should [including]:
                                      b. encourage the maintenance and enhancement of the
                                      Region’s wider biodiversity resources, giving priority to i) the
                                      protection and enhancement of specific species and habitats…
                                      of national and sub-regional Encourage importance as
                                      identified in the West Midlands Regional Biodiversity Audit,
                                      Local Biodiversity Action Plans and other BAPs; ii) those that
                                      receive statutory protection.
                                      f. apply measures set out in Policy QE1 for the treatment of
                                      biodiversity… conservation in policies, proposals and
                                      allocations in development plans, development briefs,
                                      environmental assessments, supplementary planning guidance
                                      and planning applications.
The Water Environment                 Policy QE10
                                      Development plan policies and plans of the Environment
                                      Agency and other agencies should be co-ordinated to
                                      b. Manage demand, conserve supply, use sustainable
                                      drainage to reduce wastage and promote local recycling f
                                      water and multiple use of water resources.
Climate Change                        Policy QE14
                                      Development Plans and other strategies should take into
                                      account the land use implications of the predicted climate
                                      change scenarios for the West Midlands. Particular emphasis
                                      needs to be given through policies to meeting the Regional
                                      targets for reducing carbon dioxide and other greenhouse
                                      gases. & Ecology Consultancy Ltd                                                                72
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The Birmingham Plan (1993)

The Plan has been under review; draft Alterations to the Plan were published in 2001
and 2002, the revisions were subject to Inquiry in 2003, and the City Council is to roll
it forward to the year 2011.

Chapter 3                                3.1 The quality of the environment within the City is of fundamental
Introduction                             importance in relation to the quality of life of the City’s residents.
                                         Achievement of the twin objectives of urban regeneration and economic
                                         revitalisation is dependent on creating within the City an attractive and
                                         safe environment, both to benefit existing residents and businesses, and
                                         to ensure that new investment continues to be attracted.
                                         3.4 Nevertheless, it must also be recognised that the City has a number
                                         of serious environmental problems. Its image is still too often that of a
                                         concrete jungle dedicated to the service of the motor car rather than
                                         people. While this image contains much that is exaggerated, it cannot
                                         be denied that the quality of many of the redevelopment schemes
                                         carried out in the 1950s and 60s has proved to be poor, both in terms of
                                         design and construction. Although some progress has been made, some
                                         of the physical legacy of the economic recession of the early 1980s is
                                         also still with us particularly in the inner areas of the City, where access
                                         to quality open space is also often restricted.
                                         3.7A      The UDP environment strategy, together with the corporate
                                         Sustainability Strategy and Local Agenda 21 process, have a central
                                         role in the City Council’s desire to move towards a more sustainable
                                         pattern of development. One aspect of this is a commitment to protect
                                         the significant number of environmental assets which the City already
                                         possesses and to avoid, or at least minimise, the harmful effects of new
                                         development. However, the strategy is not concerned simply with
                                         protection - it is equally concerned with improving quality across the
                                         whole city. A key element in achieving this will be to take advantage of
                                         the opportunities provided by proposals for new development and
                                         redevelopment to create high quality new environments and improve
                                         what already exists. The West Midlands Regional Sustainability Strategy
                                         and Bio-diversity Action Plan provide a context for this. Supplementary
                                         Planning Guidance will be prepared, which will examine in more detail
                                         opportunities to secure more sustainable forms of development.
                                         3.11 Positive action to improve the quality of the environment will also
                                         be required. There are a multitude of initiatives which aim to achieve
                                         this, and past experience has shown that the concentration of activity in
                                         particular areas is likely to produce the best results. Within this context
                                         the following priorities will apply:-
                                         (a) The City Centre.
                                         (b) The remainder of the inner city (including Birmingham Heartlands)
                                               and outlying estates where deprivation is concentrated.
                                         (e) Schemes which will encourage major new development consistent
                                               with the UDP Strategy.
The Built Environment                    3.13 Improving the quality of the built environment within the city is one
                                         of the most important of the UDP’s objectives. The City’s image is
                                         damaged more by the quality of its built environment - particularly in the
                                         City Centre - than any other single factor. This reputation reflects the
                                         poor quality of the rapid redevelopment - including road schemes -
                                         which took place in the 1950s and 1960s, typified by poor design,[and]
                                         inappropriate building materials. Already there are pressures for the
                                         redevelopment of many schemes: this presents an unexpected
                                         opportunity to remedy some of the mistakes of the past. & Ecology Consultancy Ltd                                                                73
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The Design of New                        3.14 A high standard of design is essential to the continued
Development                              improvement of Birmingham as a desirable place to live, work and visit.
                                         The design and landscaping of new developments will be expected to
                                         contribute to the enhancement of the City’s environment. Good design
                                         may also help to promote and secure sustainable forms of
                                         3.14A In order to ensure a high standard of design in all new
                                         developments in accordance with the advice set out in PPG 1 – General
                                         Policy and Principles, the City Council has set out below a series of
                                         general good design principles. These are concerned with the design of
                                         and the relationship between buildings, streets, squares, parks, nature
                                         conservation areas, waterways and other spaces that make up the
                                         public domain. This includes the nature and quality of the public domain
                                         itself, the relationship of one part of the City with other parts, and the
                                         patterns of movement and activity which are thereby established.
                                         3.14B In submitting applications for new development, including
                                         outline applications, developers will be expected to demonstrate that
                                         the scheme has been considered as part of its context. [All] development
                                         proposals should be accompanied by a short written statement setting
                                         out the design principles adopted. In addition, all proposals should be
                                         accompanied by plans, elevations and drawings or photographs
                                         showing the site and the proposed development in relation to the
                                         surrounding buildings and uses. Where appropriate, developers should
                                         also provide illustrations showing the impact of their proposals at a
                                         detailed level.
                                         3.14C Development should have regard to the development guidelines
                                         set out in “Places for All,” “Places for Living,” the Birmingham Nature
                                         Conservation Strategy, the Conservation Strategy, the Canalside
                                         Development Design Guidelines and any other relevant Supplementary
                                         Planning Guidance.
Good Urban Design Principles             3.14D Applications for new development will be assessed against the
                                         following principles [including]:
                                         •      The City Council will have particular regard towards the impact that
                                                the proposed development would have on the local character of an
                                                area, including ...building lines, boundary treatments, views,
                                                skyline, open spaces and landscape;
                                         •      Local characteristics which are considered detrimental in terms of
                                                urban design and which undermine the overall character of the
                                                area should not be used as a precedent for the design of new
                                         •      The scale and design of new buildings and spaces should
                                                generally respect the area surrounding them, and should reinforce
                                                and evolve any local characteristics, including natural features
                                                such as watercourses, which are considered to be positive;
                                         •      Landscaping should be an integral part of all major development
                                                proposals, and this should be designed to complement the new
                                                development and the surrounding area; & Ecology Consultancy Ltd                                                               74
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Design Principles for                    3.14E Development has a large impact on issues such as global
Sustainable Development                  warming, resource depletion and pollution. Developments, including new
                                         and refurbished buildings, should therefore be designed in a way which
                                         reduces such harmful impacts and respects the principles of a
                                         sustainable environment. Applications for development will be assessed
                                         against the following principles [including]:
                                         Existing buildings should be re-used wherever possible and where re-
                                         use would contribute to environmental quality;
                                         Consideration should be given to the use of environmentally friendly
                                         materials, including the re-use of materials, where appropriate;
                                         The orientation, external and internal design of buildings, and use of
                                         landscaping, should maximise the use of natural heat and light,
                                         contribute to local biodiversity and minimise the use of non-renewable
                                         energy sources. The use of renewable energy sources will be actively
                                         encouraged. This should not, however, be at the expense of good urban
                                         Good thermal and noise insulation should be provided;
                                         Consideration should be given to measures that will minimise the
                                         consumption of water, for example by the re-use of grey water and water
                                         saving devices and practices. Further policies on sustainable use of
                                         water and sustainable drainage are included in paragraphs 3.71-3.76;
                                         Buildings should be long-life and flexible and capable of being adapted
                                         for a variety of other uses with the minimum of disruption;
                                         3.14F The principles set out above will be applied throughout the City,
                                         including rural areas, as appropriate. More detailed guidance for
                                         particular areas/sites will be provided through Supplementary Planning
Nature Conservation                      3.37 The importance of safeguarding and enhancing the natural
                                         environment of the City is recognised. This involves both the protection
                                         of existing areas of nature conservation importance and measures to
                                         improve the diversity and quality of wildlife habitats throughout the City.
                                         Development which may destroy or adversely affect any Site of Special
                                         Scientific Interest, Local Nature Reserve or Site of Importance for Nature
                                         Conservation identified in the UDP or subsequently identified will not
                                         normally be allowed, and then only if and when compensatory measures
                                         are provided to offset (through substitution, replacement or
                                         regeneration) the loss of, or impact on, a resource present on a site or
                                         3.38 Schemes including reclamation of derelict land, and new
                                         developments, particularly those on open land, will be expected to
                                         respect, and where possible enhance, the local environment, for
                                         example through the retention of existing trees and through planting and
                                         landscaping schemes using native species where appropriate, with the
                                         objective of maximising wildlife value. Development proposals which
                                         lead to the loss of a valuable wildlife habitat should make provision for a
                                         replacement habitat of equal value.
                                         3.39 A comprehensive Nature Conservation strategy has been
                                         prepared and adopted as Supplementary Planning Guidance. This
                                         identifies those parts of the City which are particularly valuable from a
                                         nature conservation aspect, [and] acknowledges and recognises the
                                         value of green corridors and networks. Those parts of the City currently
                                         lacking in wildlife habitats are identified in the strategy as Wildlife Action
                                         Areas. Policies to ensure local biodiversity, appropriate management
                                         and adequate public access are included. These may be secured
                                         through the use of Section 106 agreements. In addition, the Birmingham
                                         and Black Country Biodiversity Action Plan provides additional
                                         information supporting the Nature Conservation Strategy. & Ecology Consultancy Ltd                                                                  75
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March 2004

Open Space                               3.47 The policy will continue to be to develop an integrated and linked
                                         [network of open space throughout the City. The linking element is
                                         provided by linear open spaces ensuring a range of recreational facilities
                                         accessible to all and enabling the natural wildlife of the countryside to
                                         penetrate deep into the urban area.
                                         3.50 Proposals for development which would have an adverse effect on
                                         this open space [network will not be allowed, and the completion and
                                         extension of the network of open space will be a priority.
Water and Drainage                       3.71 The City Council recognises the importance of the natural
                                         watercourse system in providing essential drainage. The City Council
                                         also wishes to protect water resources by minimising the use of water,
                                         and to improve water quality. Proposals for new development will
                                         therefore be expected to take account of any effects they might have
                                         upon water and drainage and to consider using rain water as a resource.
                                         3.71A The effects of development should be dealt with at or as near as
                                         possible to source in order to mitigate any detrimental effects and
                                         protect the resources. The City Council will have regard to the issues
                                         raised in the West Midlands - Tame Local Environment Agency Plan
                                         (LEAP) and in the forthcoming Environment Agency Action Plan, and will
                                         consult with the Environment Agency on planning applications for
                                         developments affecting water resources and drainage
                                         3.72     The impact on the water table must be considered for all new
                                         developments. In general, the removal of rainwater from the natural
                                         drainage system should be avoided unless the water is to be used as a
                                         resource. The full potential for the use of Sustainable Urban Drainage
                                         System (SUDS) must always be reviewed before any rainwater/run-off
                                         is diverted into sewers or storm water drains. Wherever possible,
                                         rainwater should drain into the ground, via adequate control devices.
                                         3.73     New development should also avoid polluting ground and
                                         surface water. Development should be served by adequate full drainage
                                         and treatment facilities. Any development involving the use of chemicals
                                         or resulting in contaminated surface water run-off should include
                                         adequate pollution prevention measures. Where feasible, surface run-
                                         off and contaminated water should be treated at source, through the use
                                         of “natural” features such as reed beds.
Energy                                   3.79     The City Council is aiming to minimise energy consumption and
                                         carbon dioxide emissions within Birmingham, and will require
                                         development which minimises or reduces energy consumption and
                                         carbon dioxide emissions, thereby reducing the City’s impact on global
                                         warming, resource depletion and pollution. This will be addressed in a
                                         number of ways, including:-
                                         •        locating the most intensive forms of development within the City
                                         Centre or other centres and along public transport corridors (see
                                         Chapter 2)
                                         •        building design which reduces energy consumption by
                                         maximising natural heat and light and using renewable energy. & Ecology Consultancy Ltd                                                              76
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March 2004

Nature Conservation Strategy (1997)
The Nature Conservation Strategy for Birmingham was adopted as
Supplementary Planning Guidance in November 1996 (and published in
March 1997). It is one of the first nature conservation strategies for an urban
area to be developed following the Earth Summit in 1992. The Local
Government Management Board have described it as a pioneering document,
because it develops in an innovative way the key themes of sustainability and

The task of the Nature Conservation Strategy is to ensure that, whilst the use
of land and buildings will continue to change, the City's nature conservation
resource is there for future generations to enjoy. The Strategy follows the
statutory land use policies set out in The Birmingham Plan (the City's Unitary
Development Plan) and Birmingham's Green Action Plan.

Nature Conservation and               Policy One
Development                           The City Council will seek itself and encourage others to
                                      conserve and enhance biological diversity within Birmingham
                                      and to contribute wherever possible to the conservation of
                                      national and global biodiversity.
                                      Policy Nine
                                      The City Council will, wherever possible, protect other natural,
                                      semi-natural and wildlife-rich artificial habitats in the City, as
                                      part of Birmingham's stock of Constant Natural Assets against
                                      development which may destroy or adversely affect their
                                      nature conservation value, and by seeking to prevent other
                                      forms of damage. Efforts will be made to maintain the stock of
                                      Constant Natural Assets habitats and wherever possible to
                                      increase them.
                                      Policy Sixteen
                                      Where development damaging to the City's nature
                                      conservation resource is unavoidable, the City Council will,
                                      where possible, take steps to ensure that negative impacts on
                                      existing features are minimised and opportunities for positive
                                      nature conservation impacts are maximised.
Habitat Creation                      Policy Twenty
                                      The City Council will, itself, and in liaison and partnership with
                                      others, seek to expand the City's nature conservation resource
                                      through the creation of new wildlife habitats and natural
Pollution                             Policy Thirty Two
                                      The City Council will, in conjunction with other agencies, seek
                                      to reduce existing pollution and ensure that new pollution is
                                      kept to a minimum, having particular regard to its effects on the
                                      City's nature conservation resource.
Nature conservation:                  A Strategy like this can only be successfully put into action if all
Guidelines for Action                 sections of the community play their part. Everyone can do
Introduction                          something to help Birmingham's wildlife and to look after the
                                      places where it lives. Every City Council department, school,
                                      private company, public service, community group and
                                      development agency can play its part. This section gives some
                                      ideas to help people to take effective action.
Developers                            Before buying land ascertain its nature conservation value:
                                      seek to retain and incorporate natural features in new
                                      developments and seek expert advice if necessary. & Ecology Consultancy Ltd                                                                    77
Green Roofs – Benefits and cost implications
March 2004

                                      Where a landscape scheme is required as part of planning
                                      permission try to create new habitats: plant trees and shrubs, if
                                      possible, from local seed sources or create ponds. Avoid
                                      simply putting down rye grass and planting exotic trees.
Business Sector                       Find out the wildlife value and potential of your land (see
                                      Strategy Map) and ensure its wildlife interest is retained by
                                      suitable management. Seek expert advice from the City
                                      Council or other specialists.
                                      Enhance the nature conservation value of your land by habitat
                                      creation: plant trees, shrubs and flowers; create a pond and
                                      introduce a bird bath and bird table and provide signs, seats
                                      and paths to encourage your employees and clients to enjoy
                                      the wildlife in your grounds.
                                      Consider joining the Midlands Environment Business Club and
                                      network with other businesses with an interest in nature
                                      conservation in the City.
                                      Sponsor events, awards and competitions to generate ideas
                                      and practical action for the local environment.
Private Landowners                    Enhance the conservation value of your land by habitat
                                      creation: a new pond, or additional planting of trees and
                                      shrubs, perhaps from local seed sources.
Government Departments                Provide advice and information on wildlife issues for
and Special Environmental             landowners, local communities and the City Council (especially
Agencies                              relevant for agencies with specialist conservation staff such as
                                      English Nature, The Environment Agency and British
                                      Manage your own sites to enhance or create wildlife value, for
                                      instance by appropriate management and additional planting of
                                      trees and shrubs, perhaps grown from local seed sources.
                                      Provide sponsorship and grant aid for nature conservation
Managers of Public                    Consider habitat creation by planting new trees, shrubs and
Buildings                             flowers, creating a pond and introducing bird baths or bird
                                      tables. & Ecology Consultancy Ltd                                                                 78
   Green Roofs – Benefits and cost implications
   March 2004



BAP – Biodiversity Action Plan
BBCAP – Birmingham and Black Country Action Plan
CABE – Commission for Architecture and the Built Environment
HAP – Habitat Action Plan
LBAP – London Biodiversity Partnership & Ecology Consultancy Ltd                   79
 Green Roofs – Benefits and cost implications
 March 2004


 Contacts and relevant links

 Green Roof Suppliers

 Alumasc-Exteriors Ltd – one of the leading green roof companies in the UK

 Blackdown Horticultural – consultants who design, supply and install and install green

 Erisco Bauder – another of the leading green roof companies www.erisco-

 Miller Roofing – install the sarnavert green roof system,

 Sarnafil – supply the sarnavert system

 There are a number of other companies that can supply green roofs. Although there
 is no code of practice for green roofs in the UK, the above are known to follow
 guidelines as laid out by German FSL or Swiss guidance and most produce a
 complete system as opposed buying in various elements. It is safe to say that these
 companies are the leading green roof suppliers in the UK.


 Archetype Ltd – sustainable architecture practice that have designed a number of well
 known green roofs in the UK

 Blackdown Horticultural – specialist consultancy on aspects of green roofs

 Ecoschemes Ltd - ecological consultancy with a long track record of green roof
 design and its founder, Gary Grant, was the principal author of English Nature’s
 recent report on green roofs - the first non-profit and independent green roof organisation in
 the UK.

 Ecology Consultancy Ltd – ECL has had a long involvement with urban ecological
 issues and green roofs. ECL Managing Director, John Newton, was the co-author
 with Jacklyn Johnston of Building Green, and Director Barry Nicholson contributed to
 Ecoschemes report on green roofs for English Nature.

 Information - green roofs for Healthy Cities, the North American Green Roof
 Organisation. - Atlanta based green roof website & Ecology Consultancy Ltd                                                80
Green Roofs – Benefits and cost implications
March 2004 - the International Green Roof Institute’s website. This
organisation is based in Malmo, Sweden. - the first independent/not for profit organisation in the UK set up
to promote green roofs in urban and rural regeneration. & Ecology Consultancy Ltd                                                  81
 Green Roofs – Benefits and cost implications
 March 2004


 Brenneisen, S. (2001), Vogel, Kafer und Spinneren auf Dachbegrunungen –
 Nutzungsmoglichkeiten und Einrichtungsoptimeierungen. Geographisches
 Institut Universitat Basel/Baudepartment des Kantons Basel-Stadt, Basel.

 Brownlie, S. (1990), Roof gardens; a review. Urban Wildlife Now, 7, Nature
 Conservancy Council, Peterborough.

 Corporation of London and British Council of Offices (2003), Green roofs; an
 advice note.

 DEFRA (2002), Working with the grain of nature: A Biodiversity Strategy for
 England, Department for the Environment, Food, and Rural Affairs, London.

 DEFRA (2003), Achieving a better quality of life: Review of progress towards
 sustainable development, Government Sustainable Development Report
 2002, Department for the Environment, Food and Rural Affairs, London.

 DETR (2000), Our towns and cities: the future – delivering an urban
 renaissance. Department of the Environment, Transport and the Regions,

 Frith, M. (2003), Pretty vacant?, Spaces & Places, 4, pp5-7, Urban Parks
 Forum, Reading.

 Frith, M. and Gedge, D. (2000), The black redstart in urban Britain; a
 conservation conundrum?, in British Wildlife, 11, 6, August 2000, pp 381-388,
 British Wildlife Publishing, Hook.

 Frith, M, Sinnadurai, P, and Gedge, D., (1999), Black redstart – an advice note
 for its conservation in London. London Wildlife Trust.

 Gedge, D (2003), From rubble to redstarts…, Black Redstart Action Plan
 Working Group, Green Roofs for Healthy Cities, Chicago.

 Gedge, D. (2001) Roofspace – a place for brownfield biodiversity? ECOS 22

 Grant, G., Engleback, L., and Nicholson, B. (2003), Green roofs; existing
 status and potential for conserving biodiversity in urban areas. English Nature
 Research Report 454 English Nature, Peterborough.

 Greater London Authority (2002), The draft London Plan; Draft Spatial
 Development Strategy for Greater London, Greater London Authority.

 Greater London Authority (2003), Green light to clean power; the Mayor’s
 Draft Energy Strategy, Greater London Authority. & Ecology Consultancy Ltd                                         82
Green Roofs – Benefits and cost implications
March 2004

Greater London Authority (in draft), Supplementary Planning Guidance on
Sustainable Design and Construction, Greater London Authority.

Ingleby, A. M. J., (2002), Green roofs; A study of their benefits, and barriers to
their installation in London, unpublished MSc thesis, London.

Johnston, J., and Newton, J. (1993), Building Green: A guide to using plants
on roofs, walls and pavements, London Ecology Unit.

Johnston, J. (1995), Roof-top wildlife, in Enact, 3, pp19-22, English Nature,

Jones, R. A. (2002), Tecticolous invertebrates; A preliminary investigation of
the invertebrate fauna on ecoroofs in urban London, English Nature, London.

Kadas, G. (2002), Study of invertebrates on green roofs; How roof design can
maximise biodiversity in an urban environment, unpublished MSc thesis,
University College London.

London Development Agency, English Nature and Greater London Authority
(2003), Design for biodiversity: A guidance document for development in
London. LDA, London.

FLL (1995), Guidelines for the Planning, Execution and Upkeep of Green-Roof
Sites (English version). Forschungsgesellschaft Landschaftentwicklung
Landschaftbau e. V., Bonn.

Meech, H. (2001), Wildlife and Buildings: Technical guidance for Architects,
Builders, Building Managers and Others, Estates Department, National Trust,

Scholfield, J. and Waugh, M. (Eds), (2003), Brownfield?, Greenfield? The
threat to London’s unofficial countryside, London Wildlife Trust.

Urban Task Force (1999), Towards an urban renaissance, E&FN Spon,
London. & Ecology Consultancy Ltd                                            83

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