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					  BUILDING CONTROL
      GUIDANCE
              FOR
    NEW DWELLINGS
      & GARAGES
 Dwellings upto 2 storeys with
additional guidance for 3 storeys




                      OCTOBER 2010: EDITION 5
Introduction
This document intends to provide education and guidance on how some of the technical
design and construction requirements of the Building Regulations 2010 can be achieved
and met for new dwellings up to two storeys in height and within 4.5m of ground level
and additional guidance is given for three storeys in height which has a floor 4.5m above
ground level.

In all cases the design and construction of the proposed works is the responsibility of the
designer, applicant and contractor and should be carried out to the relevant submitted
and approved design. For further information reference should be made to the relevant
Approved Document or standard as well as consulting a suitably qualified and
experienced construction professional.

The Approved Documents, which are listed below are available to view on the
Communities and Local Government web site: www.communities.gov.uk or to purchase
from The Stationary Office (TSO) on line at www.tsoshop.co.uk or telephone: 0870 600
5522.

However, the Building Regulation requirements may be satisfied in other ways or non-
standard ways by calculations or test details from a manufacturer or an approved 3rd
party method of certification such as BBA (British Board of Agreement) Certificate.

This document can be made available on a range of other formats if required. For further
information please contact us on 01594 810000.

Approved Documents and sections they cover;
A:    Structure (2004 edition) including TRADA span tables for solid timber members in
      floors, ceilings and roofs for dwellings (2nd edition 2008)*;
B1: Fire safety in dwelling houses (2006 edition);
C:    Site preparation and resistance to contaminants & moisture (2004 edition);
D:    Toxic substances (1992 with 2002 amendments);
E:    Resistance to the passage of sound (2003 with 2004 amendments);
F:    Ventilation (2010 edition);
G:    Sanitation, hot water safety and water efficiency (2010 edition);
H:    Drainage and waste disposal (2002 edition);
J:    Combustion appliances & fuel storage systems (2010 edition);
K:    Protection from falling, collision and impact (1998 with 2002 amendments);
L1A: Conservation of fuel and power in new dwellings (2010 edition);
M:    Access and use of buildings (for disabled, 2004 edition)
N:    Glazing – Safety in relation to impact, opening & cleaning (1998 with 2000
      amendments);
P:    Electrical safety (2006 edition);
Regulation 7 Materials and workmanship (1992 with 2000 amendments).

Other guidance documents available: New extensions/garages, Loft
Conversions, Commercial/industrial buildings & Fire Safety for Conversion of buildings
into Holiday Lets, Guest Houses & Supervised Groups with Learning Difficulties.

Important note: Typical section details have been provided in these guidance notes
for the more common construction methods used in dwellings. These details are
suggested methods of construction and are for guidance only. You are advised to contact
a suitably qualified and experienced property professional for details and specifications
for the most suitable form and method of construction for your project.

                                                                                              2
CONTENTS                                                                                                 PAGE NUMBER
INTRODUCTION                                                                                             2
1.0     ENGAGING A PROPERTY PROFESSIONAL                                                                 7
2.0     OBTAINING BUILDING REGULATIONS APPROVAL
3.0     EXEMPT BUILDINGS & WORK                                                                          8
4.0     COMPETENT PERSON SCHEME
5.0     PLANNING PERMISSION, LISTED BUILDING & CONSERVATION AREA CONSENTS
6.0     THE PARTY WALL ACT 1996                                                                          9
7.0     CONSTRUCTION (DESIGN MANAGEMENT) REGULATIONS AND HEALTH &
        SAFETY AT WORK ACT
8.0     GENERAL TECHNICAL & PRACTICAL GUIDANCE FOR PROJECTS                                              10
        PREPARATION, PROTECTION, ACCESS AND DEMOLITION
        PART A: STRUCTURE                                                                                11
        A1: SUB STRUCTURE
                 Foundations (including basements)
                Diagram 1: Elevation of stepped foundation
                Ground bearing solid concrete floors                                                     12
                Diagram 2: Typical section through a ground bearing solid concrete floor & foundation
                Suspended beam & block ground floor
                Diagram 3: Typical section through a suspended beam & block ground floor                 13
                Suspended timber ground floor
                Diagram 4: Typical section through a suspended timber ground floor                       14
                Table 1: Ground floor & suspended ground floor insulation requirements
                Garage concrete floor                                                                    15
                Diagram 5: Typical section through a garage floor & foundation
        A2: SUPERSTRUCTURE                                                                               16
                Cavity walls
                Table 2: Insulation requirements for external cavity walls
                  Semi Exposed Walls
                  Table 2.1: Insulation requirements to semi exposed walls
                  External timber framed walls with separate brick or block finish                       17
                  External timber framed walls with render finish                                        18
                  Diagram 6: Typical section through external timber framed walls with render finish
                  External timber framed walls with cladding finish                                      17
                  Diagram 7: Typical section through external timber framed walls with cladding finish   19
                  Detached garage with SINGLE SKIN external walls
                  Diagram 8: Design criteria for small detached single storey garages or similar         20
                  Plan view of garage
                  Wall abutments                                                                         21
                  Lintels & weep holes
                  Structural columns/beams etc
                 Expansion joints
                 Strapping and restraint
                 Cavity Closers
        A3: SEPARATING WALLS & FLOORS
                 Masonry party walls separating dwellings
                 Timber frame party walls separating buildings                                           22
                 Upgrading sound insulation of existing separating walls
                 Party floors separating buildings
                 Sound testing requirements
        A4: ADDITIONAL PROVISIONS FOR 3 STOREY BUILDINGS
                 Compressive strength of masonry units
        A5: INTERNAL PARTITIONS                                                                          23
                 Internal load bearing masonry partitions
                  Internal load bearing timber stud partitions
                  Internal masonry non-load bearing partitions
                                                                                                                       3
                      Internal timber studwork non-load bearing partitions
           A6: INTERMEDIATE UPPER FLOORS                                                               24
                    Table 3: Spans for Common Domestic Floor Joist Sizes
                    Table 4: Spans for Common Trimmer Joist supporting Trimmed Joists
                    Table 5: Spans for Common Trimming Joist supporting Trimmer Joist
                    Sound insulation to floors within the dwelling                                     25
                    SVP pipe boxing
                    Exposed intermediate upper floors
                    Diagram 9: Typical section through an upper floor
                    Table 6: Insulation requirements to exposed intermediate floors
           A7: PITCHED ROOFS                                                                           26
                    Pitched roof coverings
                    Pitched roof structure
                    Roof trusses (including attic & girder trusses)
                      Cut roof construction
                      Diagram 10: Typical section through a pitched roof                               27
                      Table 7: Spans for Common Domestic Timber Rafter Sizes at 400mm spacing
                      Table 8: Spans for Common Domestic Timber Ceiling Joist Sizes at 400mm spacing   29
                      Table 9: Spans for Common Domestic Timber Purlin Sizes
                      Table 10: Permissible Clear Spans for Common Ceiling Binders Sizes
                      Roof restraint
                      Roof insulation
                      Table 11: Insulation laid horizontally between and over ceiling joists
                      Table 12: Insulation fixed between/under rafters                                 29
                      Table 13: Insulation fixed between/over rafters
                      Diagram 11: Typical roof valley detail
                      Diagram 12: Typical section through a dormer roof                                30
                    Ventilation to pitched roofs
           A8: FLAT ROOF CONSTRUCTION                                                                  31
                    Table 14: Spans for Common Flat Roof Joist Sizes                                   32
                    Table 15: Insulation Fixed Between/Under Flat Roof Joists
                    Table 16: Insulation Fixed above Flat Roof Joists
                    Diagram 13: Typical section through a flat (cold) roof                             33
                    Valleys and lead work
                    Lofts hatches, doors & Light wells to roof spaces
           PART B: FIRE SAFETY & MEANS OF ESCAPE                                                       34
                      Smoke /heat alarms
                      Means of escape windows
                      Fire doors & frames
                      Means of escape from basements
                  Permitted building openings in relation to a boundary:
                  Openings within 1.0m of a boundary & openings more than 1.0m from a boundary
                  Table 17: Permitted unprotected areas in relation to a relevant boundary
                  Fire resistance to elements of structure etc                                         35
                  Table 18: Fire resistance to common elements of structure etc
                  Surface spread of flame: wall & ceiling linings
                  Table 19: Surface spread of flame: Classification of wall & ceiling linings
                  Additional fire safety & means of escape provisions for new 3 storey dwellings       36
                  Residential sprinkler systems for means of escape
PART C: SITE PREPARATION AND RESISTANCE TO CONTAMINANTS & MOISTURE                               37
                      Horizontal damp proof courses & trays (dpc’s)
                      Vertical damp proof courses & trays etc (dpc’s)
                      Radon gas protection in sub structures
                      3 alternative methods for full radon gas protection in sub structures
                      Methane & other gas protection in sub structures
                      Tanking systems & Flood risk                                                          38

                                                                                                                 4
PART D: CAVITY WALL FILLING WITH INSULATION BY SPECIALISTS
PART E: RESISTANCE TO THE PASSAGE OF SOUND                                                    39
PERFORMANCE STANDARDS
         Party walls and floors separating new dwelling/flats.
         Party walls and floors separating conversion of buildings into new dwellings/flats
         Exemptions/ relaxations for conversion of historic buildings into dwellings/flats
PRE COMPLETION SOUND TESTING
         Testing rate requirements
         Remedial works and re-testing
NEW INTERNAL WALLS & FLOORS
PART F: VENTILATION                                                                           40
           Ventilation systems
           Purge (natural) ventilation
           Mechanical extract ventilation                                                     41
         Background ventilation
         Background ventilation: Table A & Table B                                            42
PART G: SANITATION, HOT WATER SAFETY AND WATER EFFICIENCY                                     43
PART H: DRAINAGE AND WASTE DISPOSAL                                                           44
H1: FOUL WATER DRAINAGE
         New foul water connections to the public sewer
         Foul, rain & storm water drainage systems
         Waste pipes
H2: SEPTIC TANKS, SEWAGE TREATMENT SYSTEMS & CESSPOOLS                                        45
         Existing septic tank & effluent drainage
         Non mains foul drainage waste water treatment systems
         Septic tanks
         Sewage treatment systems                                                             46
         Treatment of sewage from septic tanks & sewage treatment systems
         Drainage fields
         Drainage mounds
         Wetlands / reed beds                                                                 47
         Percolation test method to calculate area of drainage field.
         Diagram 14: Typical section through a septic tank/sewage treatment system
         drainage field                                                                       48
         Diagram 14.1: Typical drainage field layout
H3: RAINWATER DRAINAGE AND HARVESTING                                                         49
         Rainwater gutters and down pipes
         Table 20: Gutter sizes & pipe outlet sizes for drainage of roof areas
         Rainwater/ grey water harvesting storage tanks & systems
         Surface water drainage around the building
         Oil/fuel separators                                                                  50
H4: BUILDING OVER OR CLOSE TO PUBLIC SEWERS
H5: SEPARATE SYSTEMS OF DRAINAGE
H6: SOLID WASTE STORAGE
PART J: COMBUSTION APPLIANCES & FUEL STORAGE SYSTEMS                                          51
SPACE & HOT WATER HEAT PRODUCING APPLIANCES IN GENERAL
SOLID FUEL APPLIANCES UP TO 50KW RATED OUTPUT
        Construction of open fire place with recess & hearth
        Free standing stove with hearth
        Air supply (ventilation) to solid fuel appliances
           Table 21: Air supply (ventilation) to solid fuel appliances                        52
           Carbon monoxide alarms
           Table 22: Sizes of flues in chimneys
           Construction of masonry chimneys                                                   53
           Construction of factory made flue block chimneys
           Construction of factory made metal chimneys

                                                                                                   5
          Configuration of flues serving open flue appliances
        Inspection & cleaning openings in flues
        Interaction of mechanical extract vents & opened flue solid fuel appliances
        Chimney heights                                                                   54
         Repair/relining of existing flues
        Notice plates for hearths & flues
APPLIANCES OTHER THAN SOLID FUEL
        Interaction of mechanical extract vents & opened flue combustion appliances
        Gas appliances
        Oil appliances
        Gas heating appliances up to 70kw
         Oil heating appliances up to 45kW                                                55
         Renewable energy Installations
         Provision of information- commissioning certificates (testing)
FUEL STORAGE TANKS
         LPG tanks and cylinders up to 1.1 tonnes
         Oil tanks up to 3500 litres
PART K: PROTECTION FROM FALLING, COLLISION AND IMPACT                                     56
         Internal stairs, landings and changes in level of 600mm or more
         Diagram 15: Measuring rise & goings
         Diagram 16: Typical internal stair case & guarding construction details          57
         External stairs, landings and changes in level of 600mm or more
         Guarding to upper storey window openings/other openings within
         800mm of floor level
PART L: CONSERVATION OF FUEL AND POWER IN NEW DWELLINGS                                   58
TARGET & DWELLING EMISSIONS RATES
SAP RATING & ENERGY PERFORMANCE CERTIFICATE
         Fabric standards (worst acceptable standards)
         Recommended starting u values
         U values for party walls
ENERGY EFFICIENT LIGHTING                                                                 59
LIMITING THE EFFECTS OF SOLAR HEAT GAINS IN SUMMER
LIMITING THERMAL BRIDGING AROUND EXTERNAL OPENINGS
AIR PERMEABILITY & PRESSURE TESTING
         Limiting air leakage
         Pressure testing of new dwellings                                                60
         Alternative to pressure testing
PROVIDING INFORMATION
PART M: ACCESS TO AND USE OF BUILDINGS FOR DISABLED                                       61
         External ramped & stepped approach
         Accessible level door thresholds into the building
         External door opening widths
         Internal passageways/corridors widths & table
         Internal stairs                                                                  62
         Accessible switches, sockets, controls etc
         Provision of a ground floor W/C
PART N: SAFETY GLAZING, OPENING & CLEANING                                                63
         Safety glass and glazing
         Diagram 17: Glazing in windows, partitions, doors, side panels/screens & walls
PART P: ELECTRICAL SAFETY                                                                 64
        Electrical Installations
EXTERNAL WORKS- PATHS, DRIVES, PATIO & GARDENS                                            65
MATERIALS AND WORKMANSHIP                                                                 66
ADDITIONAL BUILDING CONTROL SERVICES WE CAN PROVIDE
GLOUCESTERSHIRE BUILDING CONTROL DEPARTMENTS CONTACT DETAILS                              67
USEFUL NUMBERS OF OTHER AGENCIES OR COMPANIES

                                                                                               6
1.0 Engaging a property professional
New dwellings are normally complex projects and unless you are experienced in
construction you will need to get some professional advice/help from the following:
1. Appointing a suitably qualified and experienced property professional who will prepare
drawings and designs for your proposal, obtain the necessary approvals and if required
they will also help you to find a suitable builder and manage the project for you.
2. Appointing a specialist company who can offer a one stop shop for new dwellings,
they can prepare drawings and designs for your proposal, obtain the necessary
approvals and carry out all the necessary construction works to complete the project.
3. Using an experienced builder.

2.0 Obtaining Building Regulations approval
The building owner or agent must make a building regulations application & pay a fee for
the construction of a new dwelling. All work must comply with the 2010 Building
Regulations and the technical design and constructional requirements of the current
Approved Documents A to P and Regulation - 7 Materials and Workmanship.

The person carrying out the building works is to liaise with and meet the requirements of
the LA Building Control/Certifying Body, giving required notices of stages of works as
required by the Building Regulations including:
    Foundation excavations before any concrete is laid
    Over site covering to ground floors before any concrete is laid
    Foul & surface water drainage before any pipes are covered over
    Structural timbers (upper storey floor joists/beams and roof structure before any
       coverings are fixed
    Completion of building-prior to occupation

There are two methods of making a Building Regulations application as follows:

2.1 Full Plans application
This is often thought of as the traditional way of applying for Building Regulations
Approval. The building designer will draw up detailed plans and supporting information
for the proposed scheme and will send them to us together with a completed application
form and the necessary fee which are available to down load from our web site at:
www.fdean.gov.uk. We will then check the details and following any necessary
consultations and liaisons with the building designer a Building Regulations Approval will
be issued.

Work can start any time after the application has been received although it is wise to wait
until the scheme has had its initial check under the Building Regulations, this usually
takes between two and three weeks.

Our team of surveyors will liaise with your builder and inspect the work as it progresses
on site. When the project is satisfactorily completed a Building Regulations Completion
Certificate will be issued showing that the project has been independently inspected and
that it complied with the Building Regulations.

2.2 Building Notice application
This system is best suited to minor domestic work carried out by a competent builder.
Under this scheme no formal Approval of plans is issued and work is approved on site as
it progresses. To use the Building Notice process you or your agent will need to submit a
completed Building Notice application form together with a site location plan, the
required fee, energy assessment and water efficiency calculation. The application forms
are available to down load from our web site at: www.fdean.gov.uk.
                                                                                             7
Work can commence 48 hours after the notice has been received.

When work commences one of our surveyors will meet with your builder to discuss your
intentions, to agree how the work should be carried out, agree when the work will need to
be inspected and to establish whether any further information will be required e.g.
structural calculations or drawings.

When the project is satisfactorily completed a Building Regulations Completion
Certificate will be issued showing that the project has been independently inspected and
that it complied with the Building Regulations.

3.0 Exempt buildings and work
Green Houses & agricultural buildings: Buildings used for agriculture or keeping of
animals providing no part is used as a dwelling and is more than 1.5 times its height from
a building containing sleeping accommodation
Temporary buildings: Buildings erected for less than 28 days
Ancillary buildings: Buildings used in connection with the sale of buildings or plots on
that site, or in connection with a building project or mine/quarry and contains no sleeping
accommodation.
Small detached buildings (garages, workshops or sheds): A detached single storey
building with less than 30m2 internal floor area, with no sleeping accommodation. If
constructed substantially of combustible materials it must be positioned at least one
metre from the boundary of its cartilage. Other detached buildings with less than 15m2
internal floor area, with no sleeping accommodation. (no boundary restrictions if
constructed of combustible materials)
Conservatory, porch, covered yard/way & carports: A detached single storey building
with less than 30m2 internal floor area, fitted with safety glass in critical locations in
compliance with ADN. Existing walls, doors & windows of the building separating the
conservatory or porch is to be retained or, if removed are replaced with elements that
meet the energy efficiency requirements of ADL1B. The heating system of the dwelling
must not be extended into the conservatory or porch. Carports must be open on two
sides.

4.0 Competent Person Scheme
Certain works can be carried out by an installer who is registered with a Competent
Persons Scheme and will not require building regulations approval. Further details of the
works covered by a competent persons scheme can be found at:
www.communities.gov.uk

5.0 Planning Permission, listed building & conservation area consents
Planning permission, listed building/conservation area consents may be required for your
proposed development and no works should be commenced until approval has been
given by the planning department.

If the requirements of the building regulations will unacceptably alter the character or
appearance of a historic/listed building/ancient monument or building within
a conservation area, then the requirements may be exempt or improved to what is
reasonably practical or acceptable and would not increase the risk of deterioration of the
building fabric or fittings in consultation with the local planning authorities conservation
officer. For any further information, please contact the FODDC duty planning officer on
01594 810000.


                                                                                               8
6.0 The Party Wall Act 1996
If the project affects a party wall, you may be required to give your neighbor the
required notice under the Party Wall Act.

Two months notice in writing is to be given to adjoining owner(s) for the following works
to an existing Party Wall:
     Support of beam
     Insert DPC through wall
     Raise wall or cut off projections
     Demolition and rebuilding
     Underpinning
     Insert lead flashings
     Excavations within 3 meters of an existing structure where the new foundations
       will go deeper than adjoining foundations, or within 6 meters of an existing
       structure where the new foundations are within a 45 degree line of the adjoining
       foundations.

In the event of a disagreement, a Party Wall Surveyor may be required to resolve the
dispute under the terms of the Party Wall Act. Copies of the Party Wall Act can be
obtained from the Council Offices or www.communities.gov.uk

7.0 Construction (Design and Management) Regulations 2007 (CDM)
The Construction (Design and Management) Regulations 2007 apply to every
construction project. If you are about to undertake construction work, which could include
alterations, extensions, routine maintenance, new build or demolitions, then you need to
know to what extent these Regulations will apply to you and whether you are a duty
holder under these Regulations.

With non-domestic* projects expected to last longer than 30 days, or more than 500 man
hours, you will require the assistance of an advisor called a CDM Co-ordinator, who
should be appointed at the earliest opportunity, before detailed design work is complete.

If you are a Client thinking of commissioning work, a Designer appointed to work on a
project, or a builder/developer about to undertake work, you should be aware of your
responsibilities or duties under CDM 2007.

*Non-domestic Clients are people who commission building works related to a
trade or business, whether for profit or not. This work can be carried out on a
domestic property; it is the type of Client that matters, not the type of property.




                                                                                            9
8.0 General technical & practical guidance for projects

Preparation, protection, access, demolition & ground investigation
Demolitions, existing structures to be supported & protected where necessary, any
existing sub structures (e.g. foundations and slab etc), taken up & removed off site to a
licensed tipping site. Where the demolition of a structure or part of a structure exceeds
50m3, a notice of the proposed demolition should be sent to the local authorities building
control department before works commence. Standard format notice is available to down
load at our web site: www.fdean.gov.uk.

Provide all necessary health and safety requirements including; site security, scaffolding,
access ladders, material hoists, temporary protection and working platforms etc which
are to be erected, maintained, certificated, dismantled and removed by suitably qualified
and insured specialists.

All plumbing, drainage, heating, electrical services etc to be carried out by suitably
qualified & experience specialists or registered competent persons, tested & appropriate
certification issued where required in this specification.

Any asbestos/contaminated soil/lead paint is to be inspected & removed by a specialist.
Asbestos is to be removed and disposed off site by a specialist licensed contractor as
required under the Control of Asbestos Regulations 2006.

Ground to be prepared for new works as described including location and
alteration/modifications to all existing services as necessary, including sealing up,
capping off, disconnecting, removing redundant services as necessary.

Prior to and during works, the person carrying out the works is to liaise with and meet the
requirements of the relevant Service Authorities, including the location and protection of
all services as necessary.

External paths, drives, patios, walls, fences & gardens etc, to be taken up and
relayed/extended as necessary to accommodate the new works as described.

All structural timber is to be grade C24, stress graded to BS 4978 and sawn to BS 4471.
All timber is to be protected on site to minimize moisture content which must not exceed
22%.

An initial ground investigation assessment should be carried out including a desk study
and walk over survey which should be recorded and evaluated by a suitably qualified and
experienced person, and where necessary further basic geotechnical and contamination
investigations should be carried out by a suitably qualified and experienced person.
Where the initial assessment and basic investigations identify suspected hazards, further
detailed investigations and remedial reports are required from a specialist and copy sent
to building control and approved before works commence on site.




                                                                                          10
Part A: Structure

A1: Sub structure
Foundations (including retaining walls & basements)
Foundations to be constructed at a minimum depth of 750-1000mm, below the influence
of drains, and or surrounding trees on level firm natural undisturbed ground of adequate
ground bearing capacity to the approval of the building control surveyor.

Strip foundations to be a minimum width of 600mm and thickness of 225mm and trench
fill foundations should have a minimum width of 450mm and a minimum 500mm
thickness of concrete. The concrete mix should be ST2 or GEN1.

Alternative foundation designs, i.e. raft, piles, retaining walls & basement to be designed
by a suitably qualified person and approved by building control before works commence
on site. Where applicable, a suitable basement tanking system is to be assessed &
designed by a tanking specialist suitable for the site conditions & proposed building
construction to prevent the passage of moisture into the building, which must be
approved by building control before works commence. Retaining walls require 100mm
diameter slotted ground water drainage pipe laid around the outside perimeter of any
retaining wall at 1:60 gradient and taken to a suitable sized soak away system.

Foundations are to be provided centrally positioned under all exterior, party and interior
load bearing walls, steps in foundation level should not exceed its thickness and should
overlap by twice its thickness. Two layers of B503 mesh reinforcement or stronger are to
be provided, one top and bottom with 75mm cover to the foundations in the Forest of
Dean mining and Mineral Valuer areas (please contact building control for area details).

Walls below DPC level up to 1m deep are to be constructed with two skins of 7N/mm²
100mm or 140mm if over 1m deep concrete blocks 1:3 cement mortar in-filled with
concrete to a maximum of 225mm below DPC level. Block and cavity width and wall tie
spacing, etc, to be same as the wall above, but with a row of wall ties to support the
cavity wall insulation below DPC level.

Diagram 1: Stepped foundation detail

                        Foundations should unite at
                        each change in level

                                         L

                                                                    S
                                                                    T


                        Minimum overlap L = twice height of step,
                        or thickness of foundation or 300mm,
                        whichever is the greater

                        S should not be greater than T

                        (for trench fill foundations, minimum overlap
                        L = twice height of step or 1metre,
                        whichever is the greater)



                                                                                          11
Ground bearing solid concrete floors (worst case U-value 0.25- suggested U-value
0.13 W/m².k)
Topsoil and vegetable matter to be cleared from site and floor to be in filled with minimum
150mm/maximum 600mm clean sand blinded compacted hardcore. A 300um (1200g)
continuous polythene DPM/radon barrier is to be lapped & sealed at all joints, laid over
sand blinded hardcore & linked to DPC’s in walls. Floor & external perimeter edges of
floor slab to be insulated with floor grade insulation thickness and type in Table below,
provided under a minimum 100mm thick ST2, or Gen1 concrete floor slab with a trowel
smooth surface with 25mm up stands to the external walls. A 500g polythene separating
layer is to be installed between the concrete slab and insulation if using a foil faced
polyurethane/PIR type insulation board. Insulation to be omitted and concrete thickness
increased in areas where non-load bearing partitions are built off the floor slab. Where
area of fill exceeds 600mm the floor is to be suspended as detailed in this guidance.

Diagram 2: Typical section through a ground bearing solid concrete floor
& foundation (not to scale)

                                         All external widows and doors to be double
                                         glazed (see options in specification)

                                         100mm minimum width insulation block (see
                                         options in specification)

                                         Wall grade insulation (see options in
                                         specification)

                                         50mm clear cavity if using partial fill cavity wall
                                         insulation (see options in specification)

                                         Stainless steel wall ties and spacings as detailed
        Damp proof course                                                                      65mm thick cement/sand screed
                                         in specification
        and insulated closer                                                                   (optional)
                                         100mm minimum width external wall in
                                                                                               100mm thick concrete slab
                                         materials to match existing or as specified in
                                         planning permission
        DPC 150mm above                                                                        Floor grade insulation (see options in
        ground level                                                                           specification)
                                         25mm wide insulation to prevent cold bridging
                                                                                               1200g damp proof membrane/radon
                                                                                               gas barrier

                                                                                               Sand blinded hardcore mechanically
                                                                                               compacted in 150mm layers. (floor
        radon dpc tray sealed                                                                  slab to be suspended where depth of
        with gas proof tape to                                                                 fill exceeds 600mm deep*
        dpm/radon barrier

        Back fill cavity with
        concrete                            600 x 200mm concrete strip foundation or trench fill foundation as detailed in
                                            specification, to be 750-1000mm deep depending on sub soil conditions. Actual depth
                                            to be agreed on site with building control surveyor. Foundation depths in relation to trees
                                            to be in accordance with NHBC tables- contact building control for guidance.

                                            *Note: where full radon protection is require, proprietary radon gas sumps are to be
                                            installed in sub structure & connected to a proprietary fan assisted duct system in
                                 600mm      compliance with Part C of this guidance.




Suspended beam & block ground floor (worst case U-value: 0.25-suggested U-value
0.13 W/m².k)
Remove top soil & vegetation, apply total weed killer – minimum space below underside
of floor to be 150mm. PCC beams to be supplied and fixed to beam manufacturers plan
layout and details. (copies to be sent to Building Control and approved before works
commence on site).

Typically for domestic loading and spans pre-stressed beams are 155mm deep X 125mm
wide and fixed at 520mm ctrs, minimum bearing 100mm onto DPC course and load
bearing walls. All garage floors to be designed suitable for loadings.
Clean all beams edges and lay abutting 100mm thick X 225mm wide X 440mm long
3.5kn conc blocks to BS6073 pt.1, wet and grout all joints with 1:4 cement/sand mix.
Below non-load bearing parallel partitions provide double beams.
                                                                                                                                          12
Sub structure void to be vented on opposing sides to provide cross ventilation using 225
X 150mm proprietary ventilators at 2000mm ctrs, inner ground level to be above external
ground levels.

Lay 1200g (300 um) visqueen dpm/radon barrier, with 300mm laps double welted and
taped at joints and service entry points using Radon gas proof tape, over beam & block
floor. Lay floor grade insulation over DPM to the thickness and type as indicated in table
below. Lay 500g separating layer over any foil faced polyurethane type insulation board
and lay 75mm sand/cement screed over and prepare for floor finishes as required.

Diagram 3: Typical section through a suspended beam & block ground floor
(not to scale)

                                                   Double glazed windows as detailed in specification

                                                   Cavity wall construction as detailed in specification

                                                   Continuous dpc tray sealed with gas proof tape to dpm

                                                         75mm sand/cement screed

  Damp proof course & insulated                             75mm min floor grade insulation as table 1
  closer
                                                               1200g dpm/radon barried
  Weep holes
                                                                     Pcc beam suitable for spans &
  225 x 75mm grilled air bricks                                      loadings as beam manf details
  & proprietary telescopic vents
  through opposing walls at                                                100mm dense conc blocks
  2.0m ctrs*

  DPC 150mm min above gl


                                                  dpc under beams                                          75mm min
                                                                                                           air void


   Alternative                                               75mm concrete blinding layers
   1200g DPC basic
   radon barrier over
   complete building foot
   print to comply with                                 600 x 750mm (adjusted to foundation depth)concrete trench
   NHBC requirements                                    fill foundation as detailed in specification, to be 750-1000mm
                                                        deep depending on sub soil conditions. Actual depth to be
                                                        agreed on site with building control surveyor. Foundation
                                      600mm             depths in relation to trees to be in accordance with NHBC
                                                        tables- contact building control for guidance.


                                   *Note: for full radon protection a radon fan & flue can be connected to the
                                   floor vents if required

Suspended timber ground floor (worst case U-value 0.25- suggested U-value 0.13
W/m².k)
Remove top soil & vegetation, apply total weed killer & 150mm min thick sand blinded
hardcore, lay 100mm min thick un-reinforced concrete oversite (concrete mix should be
in accordance with BS 8110, BS 5328, mix type ST2 or GEN1), on 1200g DPM which
should extend across cavity as basic Radon protection and positioned to prevent water
collection.

Allow a ventilated air space at least 75mm from the top of the oversite concrete to the
underside of any wall plates and at least 150mm to the underside of the suspended
timber floor or insulation. Provide sub floor ventilation using 225 x 75mm grilled air bricks
& proprietary telescopic vents through two opposing external walls at 2.0m ctrs to vent all
parts of the floor void. Ducts to be sealed using gas proof tap if they pass through the
Radon barrier.


                                                                                                                         13
Joists to be supported off proprietary heavy duty galvanized joist hangers. Hangers to be
built into new masonry walls or fixed to treated timber wall plate (same size as joists),
resin bolted to existing walls at 600mm ctrs using 16mm diam high tensile bolts. Where
necessary, floor joists can be supported on treated wall plates & dpc onto masonry
honeycombed sleeper walls onto oversite concrete.

Floor joists sizes as stated on plans, or table below. Joists to be grade C24 kiln dried
floor joists fixed at 400mm ctrs (depth to be increased where necessary to match floor
levels). Proprietary galvanized steel strutting to be fixed at mid span for 2.5 - 4.5m span
and 2 rows at 1/3rd points for spans over 4.5m.

Floor to be insulated with floor grade insulation thickness and type in table below, friction
fixed between joists. Fix 22mm moisture resistant t & g flooring sheets to BS 5669 type II
or II/III laid with long edge across the joists. All joints to positioned over joists, glued &
nailed using 55mm X 10g annular ring shank nails.

Diagram 4: Typical section through a suspended timber ground floor (not to scale)
                                                                Double glazed windows as specification



                                                                Insulated cavity wall construction as
                                                                Specification
             Damp proof course & insulated                      22mm moisture resistant flooring sheets
             closer
                                                                Floor joists as table 4
             Weep holes
                                                                Galv hangers built into walls or fixed to wall
             Dpc tray
                                                                plates resin bolted to walls
             225 x 75mm grilled air bricks
                                                                Insulation as table 1 fixed between joists
             & proprietary telescopic vents
                                                                & supported on battens fixed to joists
             through opposing walls at
             2.0m ctrs*

             DPC 150mm min above gl                             w/plate on dpc                                   150mm
                                                                honey combe sleeper wall                75mm     min
                                                                                                        min



              1200g DPC                                               100mm oversite concrete slab
              basic radon barrier
              over complete                                         Blinded hardcore
              building foot print
                                                                 600 x 750mm (adjusted to foundation depth)concrete trench
                                                                 fill foundation as detailed in specification, to be 750-1000mm
                                                                 deep depending on sub soil conditions. Actual depth to be
                                                                 agreed on site with building control surveyor. Foundation
                                              600mm              depths in relation to trees to be in accordance with NHBC
                                                                 tables- contact building control for guidance.

                                          *Note: for full radon protection a radon fan & flue can be connected to the floor vents if
                                          required



Table 1: Ground floor & suspended ground floor insulation requirements
        Suggested U-value: 0.13 W/m².k
       Insulation Type                      Minimum Thickness Required
       Kingspan Kooltherm K3 or             125mm (floor P/A ratio of 0.5)
       other approved with K value of 0.020
       Alternatives TBA




                                                                                                                                       14
Garage concrete floor
Power floated 150 mm thick concrete slab (concrete mix should be in accordance with
BS 8110, BS 5328, mix type ST2 or GEN1), with 1 layer A252 steel mesh positioned mid
span of slab on 1200g visqueen dpm/radon barrier on sand blinding on min. 150 well
consolidated sulphate free clean hardcore.(no reclaimed demolished material is
permitted).

1:80 fall on floor from back of garage to front garage door, floor to be thickened to
300mm at garage entrance.

Provide 25mm polystyrene compressible clay board to perimeter of walls.
If hardcore is more than 600mm deep- slab to be reinforced further, to
NHBC/LA/Engineers requirements.

100mm thick masonry step down into garage to be provided at doorways.

Diagram 5: Typical section through a garage floor & foundation (not to scale)

                        Painted render on 100mm dense
                        conc block or bricks

                        Piers built off fnds & extend full
                        height of walls & gables
                                                             150mm thick concrete slab

                                                             1 layer A 252 steel mesh mid span

                                                             1200g damp proof membrane

                                                             Slab thickened at doorway


        DPC




                            600 x 225mm concrete              Sand blinded hardcore
                            strip foundation or               mechanically compacted in
                            trench fill foundation as         150mm layers. (floor slab to be
                            detailed in specification,        suspended where depth of fill
                            750-1000mm deep as                exceeds 600mm deep)
                            agreed on site with
                            building control surveyor

              600mm




                                                                                                 15
A2: Superstructure

External walls

Cavity walls (worst case U-value 0.30- suggested U-value 0.18 W/m².k)
Walls to consist of either approved reconstituted stone facings,100mm tooled flush
jointed brickwork or 2 coat rendered 100mm dense concrete blockwork external skin
dependant upon exposure with a 100mm thick lightweight high performance 2.8N/mm²
insulation block with either a 13mm lightweight plaster finish or 12.5mm plasterboard
skimmed drylining. Ensure all gaps & all voids are sealed to prevent any air leakage.

Where required external natural stone facings to be tied to external blockwork with wall
ties as detailed below and foundation widths increased by 150mm.

Walls to be built with 1:1:6 cement mortar and tied with BBA approved 275mm long
Ancon ST1 stainless steel wall ties or other approved double dip type tie in compliance
with BS 5628 & BS EN 845-1 , built 75mm min into each wall at maximum spacing in
compliance with wall tie manufacturers details and typically at 600mm max horizontal,
450mm max vertical and 225mm max at reveals, verges and closings for cavities up to
125mm wide. For cavity widths of 100mm use 250mm long ties- see table below*.

Cavity width and insulation details to be constructed as Table 2 below to achieve a ‘U’
value of not more than 0.28 W/m².k. Wall insulation to be continuous with roof insulation
level and taken below floor insulation levels as manufacturer’s details.

Table 2: Insulation requirements for external cavity walls with 100mm dense
Brick or rendered block external skin & internal plaster/dry lining plaster finish
 Clear cavity             Insulation type &      Overall cavity      Internal Block Type
 width required           Minimum thickness      width required      & Thickness
 Partial cavity fill
 50mm                     75 mm Kingspan         125mm*              100 mm high
                          Kooltherm K8 or                            performance
                          Other approved with                         insulation block
                          K value of 0.020                           (k value 0.15 or less
 Alternatives TBA
 * Cavities can be reduced to 100mm in compliance with insulation manufacturers
 details, subject to any building warranty provider requiring a minimum clear
 cavity of 50mm

Semi Exposed Walls (worst case U-value 0.30- suggested U-value 0.18 W/m².k)
Semi exposed walls to unheated rooms such as garages etc, to be constructed and
insulated as external walls or constructed of 2.8/mm² 100mm solid dense concrete blocks
with 50 X 125mm deep timber studs or proprietary metal stud partition wall system with
insulation friction fixed between vertical studs (as detailed in table below),
finished with 12.5mm vapour checked plaster board (or 500g polythene vapour check)

Table 2.1: Insulation requirements to semi exposed walls
  Insulation Type                           Minimum Thickness mm
  Kingspan Kooltherm K12 or other           120 mm
  approved with a K value of 0.020
  Alternatives TBA



                                                                                             16
External timber framed walls with separate brick or block finish (worst case U-value
0.30- suggested U-value 0.18 W/m².k)

Design, manufacture, supply, erection & certification of the complete timber frame
including roof, walls, lintels & floors etc to be carried out by a specialist timber frame
manufacturers in compliance with structural engineers details and calculations. Shell of
building to be air sealed and fitted with protective coverings, and measures to prevent
condensation and ingress of moisture into the building. All details to be approved by
building control before works commence on site. Moisture content of timber should not
exceed 20% and to be kiln dried & grade C24, workmanship to comply to BS 8000:5. All
timber to be treated using an approved system and all fixings to be stainless steel or other
approved.

Timber framed walls to be insulated with 120mm thick Kingspan Kooltherm K12 thermal
insulation board friction fixed between studs, with12.5mm vapour checked plaster board
fixed to studs and 3mm skim coat of finishing plaster. All junctions to have water tight
construction, seal all perimeter joints with tape internally and with silicon sealant
externally.

External wall to be approved brick/reconstituted stone/ painted sand & cement render
(render to BS 5262), on 100mm medium dense external concrete as indicated on plan
layouts. Masonry walls/mortar/render specifications are contained elsewhere in this
guidance.

External masonry skin to be tied to timber frame studs (not the sheathing) using BBA
approved proprietary flexible stainless steel or other approved wall ties in compliance with
BS 5628 & BS EN 845-1, at ctrs not exceeding 600mm horizontally and 450mm vertically
and 225mm max at reveals. Wall ties should be embedded in mortar to a minimum depth
of 75mm with a slight fall towards the external brickwork. Provide proprietary flexible
water and fire resistant cavity barriers at eaves level, gable end walls and vertically at
junctions with separating walls & horizontally at separating walls with continuous dpc tray
over, installed in compliance with manufacturers details.

Ensure all gaps & all voids are sealed to prevent any air leakage.




                                                                                         17
External timber framed walls with render finish (worst case U-value 0.30- suggested
U-value 0.18 W/m².k)

Render finish (to BS 5262) applied in 3 coats at least 16mm – 20mm thick overall to
render lath. First & second coats 1:3 (cement : sand with plasticizer). final coat 1:6
(cement : sand with plasticizer) proportions by volume. Render should be finished onto
an approved durable render stop, angle beads or jointing sections- stainless steel or
other approved using drilled or shot fired fixings only. Stainless steel render lath fixed
(using stainless steel staples) to vertical studs at 600mm max ctrs. laps wired together at
150mm ctrs. (Mesh to be backed by a water resistant membrane) & fixed to:

Treated battens - 25 x 50mm preservative treated battens fixed vertically to studs at max
600mm ctrs using 75mm long hot dipped galv or stainless steel annular ring nails, fixed
to: Breathable membrane- ‘Tyvek or similar approved suitable for timber framed walls to
current BBA certification, fixed to: External quality plywood- 12mm thick marine ply wood
(or other approved) fixed to: Treated timber frame constructed using: 125/150mm x
50mm head & sole plates and vertical studs (including 2 rows noggins) at 400mm ctrs, to
s/engineers details & calculations, with 120mm thick Kingspan Kooltherm K12 thermal
insulation board friction fixed between studs, with12.5mm vapour checked plaster board
fixed to internal face of studs and finished with 3mm skim coat of finishing plaster. All
junctions to have water tight construction, seal all perimeter joints with tape internally and
with silicon sealant externally.

Ensure all gaps & all voids are sealed to prevent any air leakage.

Diagram 6: Typical section through external timber framed walls with painted
render finish (not to scale)

         Masonry paint finish

         16-20mm thick render finish
                                                       125/150 x 50mm treated stud at
         Stainless steel render lath with water        400mm ctrs
         resistant membrane to stop render
         filling cavity                                Thermal insulation as guidance
                                                       details
         25 x 38mm treated timber battens
         at 600mm ctrs fixed vertically to form        13mm vapour checked plaster
         drained cavirty                               board & skim finish

         TYVEK or similar breathable membrane          125/150 x 50mm sole plates fixed to
                                                       base
         12mm external quality plywood or
         other approved

         Stainless steel stop bead forming drip                   Construction details as
                                                                  guidance
         Insect proof mesh (non rust)




                                                                                             18
External timber framed walls with cladding finish (worst case U-value 0.30-
suggested U-value 0.18 W/m².k)

Approved timber/upvc weatherboarding/vertical wall tiling fixed with proprietary rust
resistant fixings to: 50 X 25mm treated battens/counter battens at 400mm ctrs fixed to:
Tyvek vapour permeable membrane suitable for timber framed walls & fixed as
manufacturers details to: 12mm WPB ext quality plywood sheathing (joints covered by
dpc/battens) fixed to 125/150mm x 50mm head & sole plates and vertical studs (including
2 rows noggins) at 400mm ctrs, to s/engineers details & calculations. Studs exceeding
2.5m high to be designed by Structural Engineer. 120mm thick Kingspan Kooltherm K12
thermal insulation board friction fixed between studs with 12.5mm vapour checked plaster
board fixed to internal face of studs and finished with 3mm skim coat of finishing plaster.
All junctions to have water tight construction & seal all perimeter joints with tape internally
and with silicon sealant externally.

Ensure all gaps & all voids are sealed to prevent any air leakage.

Diagram 7: Typical section through external timber framed walls with upvc/timber
weather board finish (not to scale)



                                                             125/150 x 50mm treated stud at
             Upvc weatherboarding/vertical wall tiling       400mm ctrs
             fixed with proprietary rust resistant fixings
                                                             Thermal insulation as guidance
             25 x 38mm treated timber battens                details
             at 600mm ctrs fixed vertically to form
             drained cavirty                                 13mm vapour checked plaster
                                                             board & skim finish
             TYVEK or similar breathable membrane
                                                             125/150 x 50mm soleplates fixed to
             12mm external quality plywood or                base
             other approved

             Cladding stop fillet & insect proof mesh
                                                                        Construction details as
                                                                        guidance




Detached garage with SINGLE SKIN external walls
External walls to be as elevation plans details using: 100mm brick/reconstituted stone,
matching painted sand & cement render (render to BS 5262), on 100mm dense concrete
blocks with 100 X 400mm piers with fair face finish internally at maximum 3.0m ctrs.

Floor area exceeding 36m2 will require structural engineers details & calculations to
confirm stability of the structure.

Eaves level should not exceed 3.0m and ridge height should not exceed 3.6m without
structural engineers details & calculations to confirm stability of the structure.

Size and proportion of the garage to comply with paragraph 2C38, and the size and
location of openings in building to comply with Diagram 18/19/20 of ADA, & briefly as
follows:
           o Major openings to be restricted to one wall only (normally the front entrance
              garage door(s). Their aggregate width should not exceed 5.0m and their
              height should not exceed 2.1m.

                                                                                                  19
          o There should be no other openings within 2.0m of a wall containing a major
            opening.
          o The aggregate size of openings in a wall not containing a major opening
            should not exceed 2.4m2
          o There should not be more than one opening between piers
          o Unless there is a corner pier, the distance from a window or a door to a
            corner should not be less than 390mm.
          o Isolated central columns between doorways (where applicable) to be 325 x
            325mm min.
          o Openings other than those stated above will require structural engineers
            details & calculations to confirm structural stability

Mortar mix to be 1:1:5-6 or as required by the stone/brick/block manufacturer.




Diagram 8: Design criteria for small detached single storey garages or similar (not
to scale) Sizes & proportions of building to comply with Par 2C38 & diagrams 18/19/20
of ADA


                         390mm min to
                         opening




                                                                                                                       390mm
                                                                                                                       min to
                                                                                                                       opening
                         piers at
                         3000mm
                         maximum
                         ctrs
                          Note:                                                                         100mm min
                                                                                                        dense
                          The garage floor area should not exceed 36m2                                  conc
                                                                                                        blocks or
                          Piers to be built off the foundations & extend full height of all walls
                                                                                                        bricks
                          & gables
                                                                                                      100mm min
                          Maximum roof slope to be 40 degrees, wall plates & gable ends to
                          be strapped with galvanized strapped at 2.0m ctrs

                          Maximum height to eaves 3.0m & 3.6m to ridge & should not             Piers to be
                          exceed 9.0m in length or width                                        440mm min

                          Note: If any of the above are exceeded, the building is to be
                          constructed in compliance with design details & calculations
                          from a suitably qualified person which must be approved by
                          building control before works commence




          No other
          openings
          within this                                           325mm
         2.0m zone                                               min




                                                325mm                   Pier
                                                                                              215mm
                                                   min
                                                                                              min



                                                                                                              327mm
                                                                                                                 min




Plan view of garage
                                                                                                                                 20
Wall abutments
Vertical junctions of new and old walls to be secured with proprietary profiled stainless
steel metal crocodile type system with a continuous cavity fixed with DPC and pointed
with flexible mastic as manufacturer’s details.

Lintels & weep holes
Proprietary manufactured lintels to current British Standards/Euro codes (including
specialist lintels supporting stone facings) are to be provided over all structural openings.
The positions, types, sizes, end bearings etc of lintels must be in compliance with the
lintel manufacturers standard tables suitable for the proposed loadings and clear spans.
Stop end and dpc trays to be provided above all externally located lintels in compliance
with lintel manufacturer’s details. Weep holes at 450mm centers with at least two per
opening.

Structural columns/beams etc
Non proprietary beams/columns including pad stone to be fabricated and installed in
compliance with details and structural calculations carried out by a suitably qualified and
experienced person, which must be approved by building control before works
commence on site. Dpc trays to be provided above all externally located beams. Weep
holes at 450mm centers with at least two per opening.

Expansion joints
External walls should be provided with adequately spaced and sized expansion joints, in
accordance with masonry manufactures details with adequate tying to each side of the
joint and leaf of masonry using stainless steel wall ties (normally at each block height)
and sealed externally with a proprietary flexible mastic sealant. (Normally expansion
joints are 10-12mm wide and spaced vertically at max 12m ctrs in brick work & 6m ctrs in
block work)

Strapping and restraint
Walls to be restrained at intermediate floor, ceiling and gable walls by the provision of 30
x 5 x 1000mm lateral restraint straps or other approved in compliance with BS EN 845-1,
at maximum 2m centers carried across at least 3 joists or rafters, etc, with a minimum of
38mm wide x ¾ depth noggins.

Cavity Closers
Proprietary acoustic/insulated fire stop cavity closers, or similar are to be provided to all
cavity openings/closings, tops of walls and junctions with other properties.

A3: Separating walls & floors
( Also see relevant sections in ADE)

Masonry party walls separating dwellings (U-value 0.2 W/m2.K)
Party walls to be constructed of 2 skins of plastered 100mm dense concrete block with a
clear 50mm cavity and BBA approved wall ties spaced as external walls up to the
underside of the roof and fire stopped with mineral wool or an approved proprietary
intumescent product to achieve a minimum 45dB value for airborne sound insulation.The
party wall is to be bonded/tied to the inner leaf and the junction of cavities are to be fire
stopped throughout its length with a proprietary acoustic/ insulated fire stop cavity closer
and all other vertical and horizontal cavities are to be closed in a similar manner to
provide effective edge sealing and a U-valueof 0.2 W/m2.K.



                                                                                                21
                                                                        2
Timber frame party walls separating buildings (U-value 0.2 W/m .K)
Timber framed stud walls to achieve a minimum 45 dB value for airborne sound
insulation and constructed with 100 x 50mm sawn timber studs at 400mm ctrs with
head & sole plates, with 2x 50mm thick layers ROCKWOOL RWA 45 mineral wool
friction fixed between studs, and 2x 15mm thick layers of ‘LAFARGE dB check’ wall
board fixed both sides of stud (joints staggered) with skim coat of plaster finish- as wall
board manufacturers details. No electrical fittings to be fixed into/onto party walls & all
gaps to be fire sealed & smoke stopped to the full height and width of the party wall and
upto the underside of the roof coverings using mineral wool (not glass wool) or an
approved proprietary intumescent product to provide effective edge sealing and a U
value of 0.2 W/m2.K.

Party floors separating buildings
Outside the scope of this guidance- see relevant sections in ADE

Sound testing requirements
Pre completion sound testing is required for all new/upgraded party walls/floors which
must be carried out by a suitably qualified person or specialist to demonstrate
compliance with Approved Document E and copy of test results sent to building control.

A4: Additional provisions for 3 storey buildings
Compressive strength of masonry units
The compressive strength of bricks and blocks used in three storey construction is as
follows:
(i) Outer leaf of cavity wall – Blocks & bricks to be 7N/mm2 from foundation level upto the
underside of the structural roof.
(ii) Inner leaf of cavity wall – Blocks to be 7N/mm2 from foundation level upto the
underside of the first floor level. Blocks above this level upto the underside of the
structural roof can be 2.8N/mm2.
(iii) Internal walls – Blocks to be 7N/mm2 and 140mm thick upto the underside of the first
floor level. Blocks above this level upto the underside of the structural roof to be
2.8N/mm2.




                                                                                              22
A5: Internal partitions
Internal load bearing masonry partitions
Internal load bearing walls to be minimum100mm thick 7N/mm2 dense concrete blocks
(actual wall thickness must not be less than the wall it supports above), built off suitable
foundations (as detailed above), with pre-cast concrete/proprietary steel lintels over
openings (in compliance with lintel manufacturers span tables) and walls bonded/tied to
external or party walls with proprietary ties each course and restrained by floor or ceiling
joists/trusses.

Internal load bearing timber stud partitions
Load bearing timber stud partitions and non-proprietary lintels to be in compliance with
details and calculations by a suitably qualified and experienced person, which must be
approved by building control before works commence on site.

Internal masonry non-load bearing partitions
Internal non-load bearing partitions to be constructed of 100mm 2.8/mm² dense concrete
blocks built off a thickened floor slab and tied/block bonded to all internal and external
walls at maximum 225mm centers with either a plaster or dry lined finish as the external
walls.

Internal timber studwork non-load bearing partitions
Non-load bearing stud partitions are to be constructed of 100 x 50mm soft wood with
head and sole plates and intermediate noggins fixed at 600mm with a minimum of 25
mm of 10Kg/m3 proprietary sound insulation quilt suspended in the stud and finished with
15 mm plasterboard and skim both sides.




                                                                                           23
A6: Intermediate upper floor(s)
Floor to be constructed of kiln dried structural grade timber joists with sizes and spacing
suitable for the proposed clear span as annotated on the drawing or in compliance with
Tables below. Joists to be supported by heavy-duty proprietary galvanized metal restraint
joist hangers built into walls or fixed to treated timber wall plates (same sizes as joists)
resin bolted to walls at 600mm centers using approved 16mm diameter stainless steel
fixings. Alternatively, joists can be built into walls using approved proprietary sealed joist
caps. Joists are to be doubled up and bolted together for trimmers, under partitions and
baths. Ensure all gaps & all voids are sealed to prevent any air leakage.

Floor void between joists to be insulated with a minimum thickness of 100 mm of
10Kg/m³ proprietary sound insulation quilt, ceiling to be a minimum 15mm plasterboard
and skim and floor joist covering to be a minimum of 20mm softwood tongue and groove
softwood boards or moisture resistant particle/chipboard to give overall 30 minutes fire
resistance. Floor joists to be provided with 1 row of 38 x ¾ depth solid strutting at ends
between joist hangers or proprietary galvanized struts to BS EN 10327 fixed as
manufacturers details, at mid span for 2.5 – 4.5m spans and 2 rows at ¹/3 points for
spans over 4.5m.

Table 3: Spans for Common Domestic Floor Joist Sizes (Strength Class C24)
       Size of joist        Spacing of joist (mm)
       Breadth X Depth      400                   450                600
       (mm)          (mm)   Maximum clear span (m)
       47               97  2.12                  2.01             1.75
       47               120 2.70                  2.59             2.34
       47               145 3.25                  3.13             2.84
       47               170 3.81                  3.66             3.32
       47               195 4.36                  4.19             3.81
       47               220 4.84                  4.70             4.29
       75               220 5.41                  5.26             4.91

Table 4: Spans for Common Trimmer Joist supporting Trimmed Joists
(Strength Class C24)
                             Length of trimmed joists (m)
                              1.0         2.0           3.0          4.0
       Size of trimmer (mm)  Clear span of trimmer joist (m) supporting
                             trimmed joists
       2 x 47 x 145          2.68         2.27         1.97         1.68
       2 x 47 x 170          3.21         2.68         2.33         1.99
       2 x 47 x 195          3.69         3.09         2.69         2.31
       2 x 47 x 220          4.17         3.50         3.06         2.62
       2 x 75 x 220          4.81         4.13         3.62         3.21

Table 5: Spans for Common Trimming Joist supporting Trimmer Joist
(Strength Class C24)
                              Length of trimmer joist (m)
                               1.0               2.0            3.0 max
       Size of trimming joist Clear span of trimming joist (m) supporting
       (mm)                   trimmer joist
       2 x 47 x 145           2.62               2.42           2.25
       2 x 47 x 170           3.08               2.84           2.65
       2 x 47 x 195           3.54               3.27           3.05
       2 x 47 x 220           3.99               3.70           3.46
       2 x 75 x 220           4.66               4.32           4.05
                                                                                            24
Sound insulation to floors within the dwelling
Intermediate floors to be provided with sound insulation as described in the relevant floor
section in this document.

SVP pipe boxing
SVP pipe boxing to consist of soft wood framing, 2 layers of 15mm plasterboard and skim
and void filled with mineral wall quilt for sound insulation and fire/smoke stopping. Boxing
to be continuously carried up to roof space for soil and vent pipe and provided with air
grills where an air admittance valve is used. Ensure all gaps & all voids are sealed to
prevent any air leakage.

Exposed intermediate upper floors
Semi exposed intermediate timber floors over unheated areas such as garages, porches,
walkways, and canopy’s to be insulated with the following minimum thickness and types
of insulations to achieve a U-value0.22w/m².k as in Table 6 below. Where the
construction is open to the environment a vapour barrier and proprietary external mineral
fiber or similar 30 minute fire and moisture resistant boarding is to be applied to the
underside of the floor.

Diagram 9: Typical section through an upper floor (not to scale)



                                                                                     Sound insulated stud partition
 Double glazed window bedrooms/
 inner rooms to be fitted with openings
 suitable for escape as detailed in                                                  22mm t & g moisture resistant floor boarding
 the specification
                                                                                           Strutting between joist (see
 100mm minimum width insulation block (see                                                 specification for spacings)
 options in specification)                         Damp proof course
                                                   and insulated closer                          Floor joists (see construction
  Wall grade insulation (see options in                                                          details and table in
  specification)                                                                                 specification for sizes of joists
                                                                                                 suitable for clear spans)
                                                   Galvanized steel
  50mm clear cavity if using partial fill cavity   straps at 2m ctrs built
  wall insulation (see options in specification)                                                       Sound insulation quilt
                                                   into cavity and fixed
                                                                                                       as specification
                                                   over 3 joists with
  Wall ties and spacings as detailed in            noggins
  specification

 100mm minimum width external wall in
 materials to match existing or as specified in
 planning permission                                                                         100mm dense
                                                              Floor joists doubled           concrete partitions
 Proprietary insulated steel lintels (with dpc                up under partition
 trays and stop ends) suitable for clear spans                walls & baths                  precast
 and loadings in compliance with lintel                                                      concrete/proprieteray
 manufactures standard tables                          Sound insulated plaster               steel lintols, sizes
                                                       board achieving 30                    suitable for clear spans
                                                       minutes fire resistance               as manufactures
                                                                                             standard tables



Table 6: Insulation requirements to exposed intermediate floors
        (worst case U-value 0.25-suggested U-value 0.13 W/m².k)
       Insulation Type                      Minimum Thickness Required
       Kingspan Kooltherm K3 or             125mm (floor P/A ratio of 0.5)
       other approved with K value of 0.020
       Alternatives TBA




                                                                                                                                     25
A7: Pitched roofs
Pitched roof coverings
Roof covering to consist of slate or tile and associated capping, verge/eaves details fixed
in accordance with manufacturer’s details for pitch and exposure as detailed on the
drawings. Cladding to be fixed to a minimum 25 x 50mm treated timber batten or to
manufacturer’s directions and roof timbers to be overlaid with un-tearable breathable/non
breathable roof felt underlay to BS 747 or relevant BBA certificate.

Roof to be formed from kiln-dried stress graded timbers sized, spacing, spans, bracing
and fixings as detailed on the drawing or tables below. Alternatively, the roof may be
formed from proprietary prefabricated manufactured trusses/attic trusses and bracing to
BS 5268 but both with a foil backed 12.5mm plasterboard and skim ceiling finish.

Pitched roof structure
Roof to be constructed using either manufactured roof trusses or a cut roof as follows:

Roof trusses (including attic & girder trusses)
Roof to be constructed using specialist designed and manufactured trusses (or Attic
trusses where forming room in the roof) @ 600ctrs (max) to BS 5268:3 1985 A2 94.
Trusses to be fixed and braced strictly in accordance with manufacturers details and
mechanically fixed to 100 x 50mm sw treated wall plates via galvanized steel truss clips.
Reinforced concrete pad stoned required to support girder trusses to details and
calculations by a suitably qualified person.

The person carry out the building work is to check and confirm the actual roof pitch to the
truss manufacturer prior to placing an order.

Details of trusses to be prepared by specialist designer/manufacturer, submitted and
approved by building control prior to commencing roof construction.

Cut roof construction
Roof to be constructed using kiln dried –stress graded timber. Rafters, ceiling joists,
purlin, hanger and binder sizes as stated on tables below or see TRADA Span Tables-
suitable for the proposed clear spans and all properly fixed together using approved
fixings.

Where the ceiling joists are raised above wall plate level they must be fixed within the
bottom third of the rafter using 12mm diameter high tensile bolts and steel toothed
connectors to connect each rafter and ceiling joist to prevent possible roof spread. Joists
raised above this level are to be designed by a suitably qualified person and approved by
building control before works commence.

Struts & braces to be 100 X 50mm, hips to be splayed rafter depth + 25mm (under 30
degree pitch the hips are to be designed by a suitably qualified person), lay-boards to be
the splayed rafter depth + 25mm X 32mm thick, ridges to be splayed rafter depth +
25mm, all valleys beams are to be designed by a suitably qualified person, wall plates to
be 100 x 50 fixed to inner skin of cavity wall using galvanized strapping as detailed
below. Hip rafters to have 100 X 75mm angle ties connected across wall plates in
housed joints at corners of roof & hip irons screwed to hip rafters.

Soffits, fascias and barge boards etc to match the existing or in UPVC to BS 4576,
fixed in compliance with manufacturers details.

                                                                                          26
Allow for all necessary alteration/modification of any existing adjoining roof as required to
enable the proper completion of the works and in agreement with building control.

Allow for building in as work proceeds or insertion of proprietary stepped/cavity tray dpc
to follow line of new roof 150mm above all roof/wall abutments as necessary using code
5 lead flashings. Tie new roof into the existing, alter/modify/renew existing roof coverings
and form a weather tight structure.

Fix 12.5mm foil backed plasterboard (joints staggered) and 5mm skim coat of finishing
plaster to the underside of all ceilings using galvanized plasterboard nails.

Roof pitch to (single storey) single skin buildings with walls 100mm thick should not
exceed 40 degrees without structural engineers details & calculations to confirm stability
of the structure. Cut roofs over 40° are to be braced to BS 5268.

Diagram 10: Typical section through a pitched roof (not to scale)

                                                                                  NOTE: Proprietary high level roof vents to be installed
                                                                                  where insulation follows slope of roof- equal to a
                                                                                  continuous 5mm air gap with insect screen
 Roof slates/tiles to match existing or as stated in planning permission
 fixed as manufacturers details and suitable for the pitch                            Ridge tiles to match roof coverings
 Breathable or non breathable roofing felt fixed as                                   Ridge board (see specification for details)
 manufacturers details
                                                                                      Hangers to support hangers if additional support is
 25 x 50mm treated battens at a guage to suit coverings                               required to ceiling joists (contact building control for
                                                                                      details)
 Rafters (see construction details and table
 in specification for sizes of rafters suitable for                                   Binders to support ceiling joists if they require additional
 clear spans)                                                                         support (contact building control for details)
 Ceiling joists (see construction details and table                                   Roof insulation (see options in specification
 in specification for ceiling joist sizes suitable
 for clear spans
                                                                                      Galvanized steel strapping at 2m ctrs built into
 Rain water gutter                                                                    cavity and fixed over 3 rafters with noggins as
                                                                                      detailed in specification
 Facia/soffit boards
                                                                                      Vapour checked plaster board
 Eaves ventilation equal                     Wall plates
 to a continuous 10mm                        (strapped at
 air gap with insect screen                  2.0m ctrs)           Sound insulated
 (may not be required                                             stud partition as
 with certain breathable                     Continuous           detailed in
 roof membranes)                              insulation          specification

 Double glazed window bedrooms/
                                               Proprietary insulated steel lintels suitable for spans and
 inner rooms to be fitted with openings
                                               loadings in compliance with lintel manufactures
 suitable for escape as detailed in
                                               standard tables
 the specification



Table 7: Spans for Common Domestic Timber Rafter Sizes at 400mm spacing
(Strength Class C24)
                                   Slope of Roof (degrees)
                             15-22                22-30          30-45
       Size of Rafter       Maximum clear span (m)
       Breadth X Depth (mm)
       47         100       2.52                   2.58           2.66
       47         125       3.15                   3.22           3.32
       47         150       3.76                   3.85           3.97
       47         170       4.36                   4.45           4.57
       47         195       4.87                   4.98           5.14


                                                                                                                                         27
Table 8: Spans for Common Domestic Timber Ceiling Joist Sizes at 400mm
spacing (Strength Class C24)
       Size of Ceiling Joist            Maximum clear span (m)
       Breadth X Depth (mm)
       47           97                           1.93
       47        120                             2.56
       47        145                             3.37
       47        170                             4.00
       47        195                             4.73
       47          220                            5.47

Table 9: Spans for Common Domestic Timber Purlin Sizes (Strength Class C24)
                        Slope of Roof (degrees)
                              15-22               22-30            30-45
       Size of Purlin   Spacing of Purlins (mm)
       Breadth X Depth 1500 1800 2100 1500 1800 2100 1500 1800 2100
       (mm)                      Maximum clear span (m)
       75         125   1.87 -        -      1.91  -    -    1.98 1.86     -
       75         150   2.24 2.10 1.99 2.29 2.15 2.04 2.37 2.23 2.11
       75         175   2.61 2.45 2.32 2.67 2.51 2.38 2.76 2.59 2.46
       75           200 2.98 2.80 2.65 3.05 2.87 2.71 3.16 2.96 2.81
       75           225 3.35 3.15 2.98 3.43 3.22 3.05 3.55 3.33 3.15

Table 10: Permissible Clear Spans for Common Ceiling Binders Sizes
(Strength Class C24)
       Size of Binder              Spacing of Binders (mm)
       Breadth X Depth        1200    1500    1800     2100   2400                  2700
       (mm)                        Maximum clear span (m)
       47         150         2.19    2.06    1.96      1.87  1.80                    -
       47         175         2.60    2.45    2.32      2.22  2.13                   2.05
       63         150         2.45    2.31    2.20       2.10 2.02                   1.95
       63         175         2.91    2.74    2.60       2.48 2.38                   2.30
       75         150         2.62    2.47    2.35       2.25 2.16                   2.08
       75         175         3.11    2.92    2.77      2.65  2.55                   2.46

Roof restraint
Roof and walls to be provided with lateral restraint straps across at least 3 timbers as
noted in wall section at ceiling, wall plate and verge levels with 30 x 5mm x 1m
galvanized metal straps or other approved to BSEN 845-1 at maximum 2m centers.

Roof insulation
Insulation to be fixed to manufactures details and must be continuous with the wall
insulation but stopped back at eaves or at junctions with rafters to allow a 50mm air gap
in ventilated cold roofs.

Table 11: Insulation laid horizontally between and over ceiling joists
      (worst case U-value 0.20-suggested U-value 0.13 W/m².k)
       Product                  K -Value                     Position in roof
       Crown Wool &             0.036                        200mm between joists &
       Rock-wool Roll                                        200mm laid across joists
       Alternatives TBA



                                                                                            28
Table 12: Insulation fixed between/under rafters
      (worst case U-value 0.20- suggested U-value 0.13 W/m².k)
       Product                      K -Value       Position in roof
       Kingspan Kooltherm K7        0.020          100mm friction fixed between
                                                   rafters* &
       Kingspan Kooltherm K18       0.020          82.5mm fixed under rafters

       Or other approved with a K
       value of 0.020
       Alternatives TBA
       * Where rafters are only 100mm deep, battens should be provided to their
       underside to maintain a 50mm air gap above the insulation where a non
       breathable roofing felt is used or battened to allow a 25mm sag in felt if using a
       breathable roofing membrane as the manufacturers details.

Table 13: Insulation fixed between/over rafters
      (worst case U-value 0.20- suggested U-value 0.13 W/m².k)
       Product                      K -Value       Position in roof
       Kingspan Kooltherm K7        0.020          75mm fixed between rafters &
                                                   80mm fixed over rafters
       Or other approved with a K
       value of 0.020
       Alternatives TBA


       25 x 50mm counter battens to be fixed over insulation to allow for sag in
       breathable roofing membrane as manufacturers details




Diagram 11: Typical roof valley detail (not to scale)

                                                   Roof coverings & roof structure as
                                                   specification
                                                   & section details
                             200mm
                              min




                125mm                              Breathable roofing membrane
                min
                                                   lapped over lead & forming drip

        Rafter birds                               Tiling fillet
        mouthed over 150 x
        50mm wall plate                            Code 5 lead lined gutter- lead sizes,
        (wall plated                               drips & welted joints etc to the Lead
        strapped at 2.0m                           Development association details
        ctrs
                                                   25mm treated gutter board fixed to:
        Pcc pad stone or
        dense blockwork                            50 x 50mm treated timber gutter
                                                   bearer




                                                                                            29
Diagram 12: Typical section through a dormer roof (not to scale)

                                                        Roof slates/tiles to match existing or as stated in
                                                        planning permission fixed as manufacturers details and
                                                        suitable for the pitch

                                                        25 x 50mm treated battens at a guage to suit coverings

                                                        Breathable or non breathable roofing felt fixed as
                                                        manufacturers details

                                                                          Ridge board as specification

                                                                          Rafters (see construction details and
                                                                          table in specification for sizes of rafters
                                                                          suitable for clear spans)

                     Trimming                                             Ceiling joists (see construction details
                     joists as                                            and table in specification for ceiling
                     spec                                                 joist sizes suitable for clear spans
                             Rain water gutter, facia/soffit
                             boards etc as spec                           Insulation deatils as tables in
                                                                          specification
                           Eaves ventilation equal
                           to a continuous 10mm                           Dormer walls constructed with painted
                           air gap with insect screen                     renders or cladding on insulated
                           (may not be required                           timber frame as spec details
                           with certain breathable
                           roof membranes)                                      Code 5 lead flashing & valleys

                           13mm vapour checked plaster                          Dormer roof supported on rafters
                           board & skim                                         doubled up & bolted together

                                                                                               See main roof for
                                                                                             construction details




Ventilation to pitched roofs
Roof insulation to be continuous with the wall insulation but stopped back at eaves or at
junctions with rafters to allow a 50mm air gap. Cross ventilation to be provided by a
proprietary eaves ventilation strip equivalent to a 25mm continuous gap at eaves level
with insect grill.

Alternatively, where cross ventilation is not possible such as mono pitch, coved ceiling or
room in the roof provide additional ridge/high level ventilation equivalent to a 5mm gap in
the form of proprietary vent tiles spaced in accordance with manufacturer’s details.

Ventilation to the roof space may be omitted, only if a proprietary BBA or similar
approved breathable roof membrane, with minimum 25mm thick treated vertical counter
battens and proprietary eaves carrier system is used. Breathable roof membranes &
proprietary roof vents must always be installed as manufacturers details (note: some
breathable membranes may also require additional roof ventilation)




                                                                                                                        30
A8: Flat roof construction
Flat roof to be carried out as detailed on the drawings. Moisture content of timber should
not exceed 20% and to be kiln dried & grade C24. Workmanship to comply to BS 8000:4.
All fixings to be proprietary stainless steel or galvanized steel.

Waterproof covering to be either:
   3 layers of high performance felt (hot bonded together with bitumen) to a current
      BBA Certificate in compliance with BS8217
   Single layer system with a current BBA or WIMLAS Certificate
   Glass reinforced plastic (GRP) system with a current BBA or other approved
      accreditation
   Lead sheet fixed in compliance with the Lead Development Associations guide to
      good practice
   Mastic asphalt fixed in compliance with the Mastic Asphalt Councils technical
      guides & specifications

Waterproof covering to be laid in compliance with manufacturers details by flat roofing
specialist onto separating layer over roof insulation layer in compliance with below to
form a ‘warm roof’ (or alternatively insulation fixed between/under joists in compliance
with Table below forming a ‘cold roof’) fixed to, 22mm external quality plywood decking or
similar approved laid to 1:60/80 minimum gradient using firing strips at spacing to match
joists, fixed onto timber flat roof joists constructed of kiln dried structural grade timber
with sizes and spacing suitable for the proposed clear span as annotated on the drawing
or in compliance with Table below or see TRADA Span Tables.

Flat roof to have a surface finish of bitumen bedded stone chippings covering the whole
surface to a depth of 13mm to achieve a class AA (or B (t4) European class) fire rated
designation for surface spread of flame.

Restrain flat roof to external walls by the provision of 30 x 5 x 1000mm lateral restraint
straps at maximum 2000mm centers fixed to 100 x 50mm wall plates and internal wall
faces

Flat roof insulation to be in compliance with tables below. Flat roof insulation is to be
continuous with the wall insulation but stopped back to allow a continuous 50mm air gap
above the insulation in ventilated cold decks. Cross ventilation to be provided on
opposing sides by a proprietary eaves ventilation strip equivalent to a 25mm continuous
gap at eaves level with insect grill. Note: Warm roof applications i.e. insulation above the
structural deck do not require ventilation.

The design, workmanship & selection of materials should comply with Model
Specification Sheet P.L.1 Built-Up Roofing: Plywood Deck, published by The British Flat
Roofing Council. Metallic roof trims to be of non-corrodible material & resistant to sunlight
& not fixed through the water proof covering. All timber to be treated using CCA
vacuum/pressure or O/S double vacuum to BS 5268:5, including all cut ends of timber
etc 300mm of any joint.

All flat roofing works to be carried out by a specialist flat roofing contractor and all
materials etc to be fitted in compliance with manufacturer’s details. Work should not be
carried out during wet weather or when the deck has not fully dried out. A 500g vapour
control barrier is required on the underside of the roof below the insulation level. Fix
12.5mm foil backed plasterboard (joints staggered) and 5mm skim coat of finishing
plaster to the underside of all ceilings using galvanized plasterboard nails.

                                                                                             31
Table 14: Spans for Common Flat Roof Joist Sizes (Strength Class C24)
      (Access for maintenance and repairs only)
         Size of joist     Spacing of joist (mm)
         Breadth x Depth   400                   450               600
         (mm)              Maximum clear span (m)
         47            97  2.02                  1.99             1.90
         47            120 2.65                  2.61              2.46
         47            145 3.36                  3.27              2.97
         47            170 3.98                  3.83              3.48
         47            195 4.55                  4.38              3.98
         47            220 5.13                  4.93              4.49
         75            220 5.94                  5.73              5.23

Table 15: Insulation Fixed Between/Under Flat Roof Joists
      (Vented cold roof-worst case U-value 0.20- suggested U-value 0.13 W/m².k)
                Product                   K -Value Position in roof
         Kingspan K7                      0.020        200mm between joists
         Kingspan K18                     0.021        32.5mm fixed under joists
         Or other approved with a
         K value of 0.020
         Note: The joist depth must be sufficient to maintain a 50mm air gap above the
         insulation and cross ventilation to be provided on opposing sides by a
         proprietary ventilation strip equivalent to a 25mm continuous gap at eaves level
         with insect grill for ventilation of the roof space.

Table 16: Insulation Fixed above Flat Roof Joists
      (Non vented ‘warm roof’ worst case U-value 0.20-suggested U-value 0.13 W/m².k)
         Product                       K -Value Insulation fixed above deck
         Kingspan Thermaroof           0.020      180mm fixed above deck in a single
                                                  layer
         Or other approved with a K
         value of 0.020
         Alternatives TBA




                                                                                        32
Diagram 13: Typical section through a flat (cold) roof (not to scale)



                                                            13mm diam stone chippings bedded in hot bitumen


                                                                     Water proof coverings applied by flat roofing specialist as spec.

                                                                              External quality structural decking

                                                                                     Firing strips at 1:60 min gradient

                                                                                                50mm min air gap

                                                                                                     Thermal insulation fixed above or below structural
                                                                                                     decking as guidance tables



                                                                                                            Plasterboard with vapour check

                                      1:60/80 gradient


                                                                                                                  Welted drip
   Welted drip
                                                                                                                  Rain water gutters, facia/
   25mm continuous air gap
   with insect screen                                                                                             barge board
                                             Flat roof joist sizes and spacing as
   wall plate & strapping as                 spec tables                                                          25mm continuous air gap
   spec details                                                                                                   with insect screen
                                                         Proprietary steel box beam as
   Cavity wall as spec details                           manf details suitable for clear span
                                                         or timber lintel to s/engineers
                                                         details & calculations to suit clear
                                                         spans of openings

                                 Note: if insulation is fixed above the structural deck (forming a
                                 warm roof) the above ventilation details can be omitted




Valleys and lead work
Lead work, flashing, soakers, valleys and gutters, etc, to be formed from Code 5 lead
sheet and fully supported on treated valley boards, etc, and to have a minimum 150mm
lap joints, dressed 200mm under tiles, etc, and not to be fixed in lengths exceeding 1.5m
and to be fixed in accordance with the roof cladding manufacturers and the Lead
Development Association recommendations.

Lofts hatches, doors & Light wells to roof spaces
All hatches, doors and light wells in the roof space to be insulated to the same standard
as the roof, draft stripped and positively fixed. All hatches to be accessible.




                                                                                                                                               33
Part B: Fire safety & means of escape
Smoke /heat alarms
All floors to be provided with mains operated interconnected fire detection and fire alarm
system to BS 5446 & installed in accordance with the relevant recommendations of
BS 5839 – 6: 2004 to at least a Grade D Category LD3 standard. Self contained mains
operated smoke alarms (heat alarms installed in kitchens if open to stairway) with battery
back up to be fixed at ceiling level in all circulation areas at each storey level, within 7.5m
of all doors to habitable rooms.

Means of escape windows
Means of escape windows to be fitted with proprietary hinges to open to the minimum
required clear width of 450mm. Escape windows must have minimum clear opening
casement dimensions of 0.33m² and 450mm (typically 450mm wide x 750mm high),
located within 800-1100mm above floor level to all bedrooms and habitable rooms at 1st
floor level and inner habitable rooms on the ground floor. Windows above the ground
floor storey and within 800mm of floor level are to be provided with containment/
guarding/ proprietary catches which should be removable (child proof) in the event of a
fire. Where escape windows cannot be achieved, direct access to a protected stairs (or
protected route to inner rooms) is acceptable in compliance with ADB1- par 2.6 (a) or (b).

Fire doors & frames
Walls between garage and the house to be built up off foundations in masonry to give 30
minutes fire resistance and taken upto the ceiling/roof level and fire stopped with mineral
wool. Door(s) between the house and garage to be FD30 to BS476-22:1987 fitted with
proprietary mechanical self-closers, intumescent strips and smoke seals.

Means of escape from basements
If the basement storey in served by a single stairway and contains a habitable room, the
basement should be either fitted with a means of escape window or door in compliance
with this guidance or a protected stairs leading from the basement to the final exit in
compliance with this guidance.

Permitted building openings in relation to a boundary:

Openings within 1.0m of a boundary
An unprotected opening of 1m2 (e.g. window) is permitted every 4.0m on the same
building face. This unprotected opening can consist of two or more smaller openings
within an area of 1m2 (openings less than 0.1m2 is permitted every 1500mm on the same
building face). There are no restrictions on dimensions between openings separated by
compartment walls & floors. Please refer to Diagram 20 of ADB4 Volume 1 for full details.

Openings more than 1.0m from a boundary
Permitted unprotected openings to be in compliance with table below for buildings not
exceeding 3 storeys high (excludes basements) or more than 24m long.

Table 17: Permitted unprotected areas in relation to a relevant boundary
 Minimum distance between side of                Maximum total area of unprotected
 building & relevant boundary                    openings
 1.0m                                            5.6m2
 2.0m                                            12m2
 3.0m                                            18m2
 4.0m                                            24m2
 5.0m                                            30m2
 6.0m                                            no limit
                                                                                             34
If sprinklers are fitted throughout the building to BS 9251, the above distances can be
reduced by 50% (min 1.0m) or the unprotected opening area doubled. Please refer to
ADB4 Volume 1 for full details relating to space separation and other methods of
calculating unprotected areas.

Fire resistance to elements of structure etc
Please refer to Table A1: Appendix A of ADB: Volume 1 for full details.

Table 18: Fire resistance to common elements of structure etc
 Building element                                      Fire resistance    Method of protection
                                                       in minutes
 Beam, column or frame                                 30                 All exposed faces
 Load bearing wall                                     30                 Each side separately
 Upper floors (Max 3 storey building)                  30                 Underside
 Roof (only if forming part of an escape route) 30                        Underside
 External walls:
 (i) Less than 1.0m to relevant boundary               60                 Each side separately
 (ii) More than 1.0m to relevant boundary
 (max 3 storey building)                               30                 From inside building
 Walls & upper floors separating an integral
 garage from the dwelling                              30                 From garage side
 Compartment walls & floors separating
 Dwellings                                             60                 Each side separately
 Protected stairs & lift shaft (not forming
 part of a compartment wall)                           30                 Each side separately
 Cavity barriers etc                                   30                 Each side separately
Note: 12.5mm plasterboard & skim finish applied to 100 x 50mm timber stud partitions/
ceiling/ floor joists as detailed in this specification will achieve 30 minutes fire resistance,
two layers of 12.5mm plaster board (joints staggered) will achieve 60 minutes fire
resistance. Masonry walls detailed in this specification will achieve 60 minutes fire
resistance.

Surface spread of flame: wall & ceiling linings

Table 19: Surface spread of flame: Classification of wall & ceiling linings
Please refer to Table 1: Section 2 of ADB: Volume 1 for full details.
 Location                      National class                 European class
 Small rooms upto 4m2 &        3                              D-s3,d2
 Domestic garages upto
 40m2
 Other rooms over 4m2 inc 1                                   C-s3,d2
 Garages over 40m2 &
 Circulation spaces within
 Dwellings (e.g. hall, stairs
 & landings)
Note: Plaster on masonry walls & plaster board & skim linings in this specification will
achieve class 1. Exposed timber linings should be treated with a proprietary treatment to
achieve the above classifications.




                                                                                               35
Additional fire safety & means of escape provisions for new 3 storey dwellings
The stairs is to be protected & enclosed by 30 minutes fire resisting and fire insulating
construction to the walls and partitions constructed in compliance with the relevant
paragraph above.

FD20 fire doors to BS476-22:1987 fitted with an intumescent strip rebated around top &
sides of door or frame/lining. The exit from the stairway should extend direct to a final exit
and to outside air.

All floors to be provided with mains operated interconnected smoke alarms at ceiling
level with battery back up in compliance with the relevant paragraph above.

Limitations on the use of un-insulated glazed elements on escape routes to be in
compliance with Table A4 of Approved Document B: Volume 1- Dwelling Houses.

Residential sprinkler systems for means of escape
Where fire safety requirements of the building regulations cannot be met for new
dwellings, proposals for fire engineered solutions may be allowed against the
requirements of Approved Document B where a risk assessment has been carried out by
a suitably qualified and experienced fire engineer and approved by building control
before works commence on site. The residential sprinkler system is to be designed and
installed to BS 9251:2005 incorporating BAFSA technical guidance note No.1 June 2008
by a suitably qualified specialist- which must be approved by Building Control before
works commence on site.

If the condition not being met is a ground floor open plan arrangement and the stairs
discharge into a habitable open plan area then a partial sprinkler installation to the whole
of all connected open plan areas may be used. Fire separation of the route will be
required from the upper floor from this open plan area with a 30 minute fire resisting
partition and FD20 fire door fitted with intumescent strips. Instead of the separation it may
be possible to fully sprinkler the whole dwelling and retain the open plan arrangement
with the agreement of building control.

With the agreement of the building control, it should be possible to reduce fire protection
throughout the dwelling by 30 minutes with the introduction of a full sprinkler installation.

Contact: The British Automatic Sprinkler Association (BAFSA)- Sprinklers for Safety: Use
and Benefits of Incorporating Sprinklers in Buildings and Structures (2006) ISBN: 0
95526 280 1. See also: www.bafsa.org.uk ISBN 0-9552628-3-6 technical guidance note
no.1 see also www.firesprinklers.org.uk

IMPORTANT NOTE: The above requirements for three storey dwellings need not be
followed if the dwelling house has more than one internal stairway, which afford effective
alternative means of escape and are physically separated from each other.




                                                                                            36
Part C: Site preparation and resistance to contaminants & moisture
Horizontal damp proof courses & trays (dpc’s)
Horizontal Dpc’s and Dpc trays with weep holes at 1.0m ctrs to be provided 150mm
above ground level continuous with and sealed to the floor Dpm & radon dpc tray.

Vertical damp proof courses & trays etc (dpc’s)
Stepped and horizontal Dpc/cavity trays are to be provided over all openings, roof
abutments/projections and over existing walls with different construction or materials.
Install vertical dpc or proprietary insulated cavity closers at all closings, returns,
abutments to cavity work and openings etc.

Radon gas protection in sub structures
Full radon protection is required in the sub structure to prevent radioactive gas present in
the sub soil from entering the building through cracks in the construction as detailed
below, unless it is confirmed by a radon risk report from a specialist (available from
www.ukradon) that full radon protection is not required.

Note: basic radon protection is required as a minimum standard in all sub structure floors
as detailed in Part A and relevant diagrams of this guidance.

3 alternative methods for providing full radon gas protection in sub structures
(i) Proprietary plastic radon sumps to be installed in sub floor of ground bearing slab as
manufacturers details (see www.visqueenbuilding.co.uk) and diagram 2 above. Sumps to
be connected to 110mm diameter proprietary air sealed upvc pipes, and fitted with an
access plug cap above ground level to allow connection to a radon fan & duct system-
upto eaves level of the building. A sign identifying radon pipe work is to be fixed to the
wall above the capping. 1200g DPM radon barrier is to be taped and sealed at all joints,
junctions, service entry points and sealed to a continuous cavity tray (using a proprietary
tape) which is supported by the cavity infill at ground level and brought through the
external wall leaf with weep-holes to the external skin; Or

(ii) Proprietary geo-textile drainage matting or duct system laid beneath slabs as
manufacturers details & connected to an extract pipe & fan system as detailed above; Or

(iii) Construct ventilated beam & block floor as detailed in diagram 3 above.

Further advice on radon & radon protection can be obtained from BRE at: www.bre.co.uk
& The Health Protection Agency at: www.hpa.org.uk

Methane gas & other gas protection in sub structure
Protection is to be provided in the sub structure in compliance with the provisions for full
radon protection in item above and in the following circumstances:
(i) Within 250m of a landfill site. (The Environment Agency’s policy on building
development on or near landfill sites should be followed).
(ii) On a site containing biodegradable substances (including made up ground or fill); or
subject to use that could have petrol oil or solvent spillages; or naturally occurring
methane, carbon dioxide and other hazardous gases (e.g. hydrogen sulfide).

Information regarding land contamination can be obtained from your local authority
environmental health department. Risk assessments, ground investigations and any
necessary remedial works should be carried out in compliance with Approved Document
C of the Building Regulations.


                                                                                           37
Tanking systems
Suitable tanking systems include asphalt, self adhesive bitumen membranes, drained
cavity membranes and liquid applied membranes to have BBA or other approved
accreditation and assessed by a tanking specialist as suitable for the proposed situation.

Tanking systems to be installed/applied by a tanking specialist in compliance with tanking
manufacturers details which must be approved by building control before works
commence on site.

Flood risk
Flood risk should be assessed and precautions carried out in compliance with paragraph
0.8 of ADC


Part D: Cavity wall filling with insulation by specialists
The suitability of the cavity wall for filling must be assessed before the works is carried
out by an insulation specialist in accordance with BS 8208: Part 1: 1985.

The insulation specialist carrying out the work must hold or operate under a current BSI
Certificate of Registration of Assessed Capability for the work being carried out.

The insulation material must be in accordance with BS 5617: 1985 and the installation
must be in accordance with BS 5618: 1985

The Installation of urea-formaldehyde (UF) in cavity walls is to be carried out in
compliance with paragraphs 1.1 — 1.2 of ADD1




                                                                                              38
Part E: Resistance to the passage of sound
Performance standards
Party walls and floors separating new dwelling/flats.
Sound insulation details for new party walls and floors to be carried out in accordance
with the relevant details contained within this guidance and Approved Document E as
follows: .
45 dB minimum values for airborne sound insulation to walls, floors & stairs; &
62 dB maximum values for Impact sound insulation to floors & stairs.

Party walls and floors separating conversion of buildings into new dwellings/flats
Sound insulation details for new party walls and floors to be carried out in accordance
with the relevant details contained within this guidance and Approved Document E as
follows: .
43 dB minimum values for airborne sound insulation to walls, floors & stairs; &
64 dB maximum values for Impact sound insulation to floors & stairs.

Exemptions/ relaxations for conversion of historic buildings into dwellings/flats
If the proposed sound insulation requirements will unacceptably alter the character or
appearance of a historic/listed building then the sound insulation standards may be
exempt or improved to what is reasonably practical or acceptable standard that would not
prejudice the character or increase the risk of deterioration of the building fabric or fittings
in consultation with the local planning authorities conservation officer. A notice showing
the actual sound test results is to be fixed in a conspicuous place inside the building in
compliance with paragraph 0.7 of ADE

Pre completion sound testing
Robust details to be adopted or pre-completion sound testing to be carried out to
demonstrate compliance with ADE1 as follows:

(i) Robust details
Robust Construction Purchase Certificates are to be provided by the building owner on
commencement and provide compliance certificates on completion; which must be sent
to Building Control to demonstrate compliance with ADE1. Robust Construction Details
can be obtained through Robust Details Ltd. Tel: 0870 240 8210.

(ii) Pre completion sound testing by specialist
Pre completion sound testing is to be carried out by a suitably qualified person or
specialist with appropriate third party accreditation (UKAS or ANC registration) to
demonstrate compliance with ADE1, and copy of test results sent to building control.

Testing rate requirements
At least one set of recorded tests is required for every 10 new dwellings on the same site
and additional testing may be required where requested by building control.

Remedial works and re-testing
Remedial works and re-testing will be required where the test has failed, in compliance
with Section 1 of ADE

New Internal walls & floors
Sound insulation details between internal walls & floors separating bedrooms or a room
containing a WC and other rooms to be carried out in accordance with the relevant
details contained within this guidance and Approved Document E .
                                                                                              39
Part F: Ventilation to new dwellings
Ventilation systems
System 1: Purge (natural) ventilation Background ventilation & intermittent extract fans in
compliance with table 5.2a of ADF1- as detailed below.
System 2: Passive stack ventilation in compliance with table 5.2b of ADF1.
System 3: Continuous mechanical extract in compliance with table 5.2c of ADF1.
System 4: Continuous mechanical supply and mechanical extract with in heat recovery
compliance with table 5.2d of ADF1.

System 1: Purge (natural) ventilation with background ventilation &
intermittent extract fans

Purge (natural) ventilation to habitable rooms
Purge (natural) ventilation to be provided to all habitable rooms equal to 1/20th (5%) floor
area where the external windows/doors open more than 30 degrees and increased to
1/10th (10%) of the floor area where the windows opens between 15 - 30 degrees.
Window openings which open less than 15 degrees is not suitable for purge ventilation
and alternative ventilation details are required as detailed below and in compliance
section 5 & Appendix B of Approved Document F1. Purge (natural) ventilation openings
to habitable rooms to be typically 1.75m above floor level.

Mechanical extract ventilation & fresh air inlets for rooms without purge ventilation
Mechanical extract ventilation & fresh air inlet are required for habitable rooms without
purge (natural) ventilation which must designed by a ventilation specialist having
a minimum of 4 air changes per hour & manually controlled in compliance section 5 of
Approved Document F1.

Purge ventilation to wet rooms (kitchens/utility/bath/wc/en suit etc)
Opening windows are required for purge (natural) ventilation to wet rooms (kitchens/
utility/bath/wc/en suit etc) which have external walls (no minimum sizes) in compliance
section 5 of ADF1.

General requirements for purge (natural) ventilation
Purge (natural) ventilation openings to habitable rooms to be typically 1.75m above floor
level and all internal doors to have a 10mm gap under the door for air supply transfer.

The area of external windows, roof windows & doors should not exceed 25% of the
usable internal floor area otherwise SAP calculations may be required from a suitably
qualified person to confirm design flexibility where they exceed 25% of the usable floor
area. (ii) See the relevant section in this guidance for permitted unprotected external
openings in relation to relevant boundaries.

Means of escape windows to be fitted with proprietary hinges to open to the minimum
required clear width of 450mm. Escape windows must have minimum clear opening
casement dimensions of 0.33m² and 450mm (typically 450mm wide x 750mm high),
located within 800-1100mm above floor level to all bedrooms and habitable rooms at 1st
floor level and inner habitable rooms on the ground floor. Windows above the ground
floor storey and within 800mm of floor level are to be provided with containment/
guarding/ proprietary catches which should be removable (child proof) in the event of a
fire. Where escape windows cannot be achieved, direct access to a protected stairs (or
protected route to inner rooms) is acceptable in compliance with ADB1- par 2.6 (a) or (b).


                                                                                           40
Mechanical extract ventilation to new dwellings

Mechanical extract ventilation rates
Mechanical ventilation is to be provided to the rooms listed below directly ducted to the
outside air equivalent to the following rates.

Kitchen      30 litres per second over hob or 60 litres elsewhere
Utility room 30 litres per second
Bathroom     15 litres per second (including shower rooms & en-suites)
Toilet        6 litres per second W/C (with or without a window)

Mechanical ventilation to rooms without open able windows to be linked to light operation
and have 15 minutes overrun and a 10mm gap under the door for air supply.

Note: Fans must not be installed in rooms containing open flue appliances unless the
Interaction of mechanical ventilation & open flue heating appliances is checked and
certified by an approved method & suitably qualified person as contained in ADJ.

Continuous mechanical extract
Continuous mechanical extract ventilation details are required in compliance with tables
5.1a & 5.1b of ADF1.

Whole building mechanical extract
Whole building mechanical extract ventilation details are required in compliance with
table 5.1b of ADF1.

General requirements for mechanical extract ventilation
Mechanical ventilation to rooms without open able windows to be linked to light operation
and have 15 minutes overrun and a 10mm gap under the door for air supply.

Fans must not be installed in rooms containing open flue appliances unless the
interaction of mechanical ventilation & open flue heating appliances is checked and
certified by an approved method & suitably qualified person as contained in ADJ.

Mechanical ventilation to be ducted in proprietary insulated ducts to outside through
walls to proprietary vent or through roof space to proprietary matching tile /soffit vent

Background ventilation to new dwellings
Background ventilation to be provided to all rooms with external walls either through
walls or in windows via hit and miss or 2 stage window catches equivalent to
5000mm2 minimum to each habitable room and 2500mm2 minimum to each wet
room (kitchens/utility/bath/wc/en suit etc).

The total area of background ventilation must be in compliance with Table 5.2a of ADF1
as follows:
(i) For dwellings with any design air permeability use Table A below
(i) For dwellings with design air permeability worse than 5m3 /(h.m2) use Table B below

Background ventilation to be located typically 1.75m above floor level.

Note: For buildings with no external walls use appropriate ventilation system 2,3 or 4 in
compliance with paragraphs 5.8- 5.10 of ADF1.

                                                                                            41
Table A:Total background ventilation (mm2) required for new dwellings with any
design air permeability
                                    Number of bedrooms
 Total floor area (m2)     1          2        3        4       5
 Less 50                  35000      40000    50000    60000    65000
 51-60                    35000      40000    50000 60000       65000
 61-70                    45000      45000    50000 60000       65000
 71-80                    50000      50000    50000 60000       65000
 81-90                    55000      60000    60000 60000       65000
 91-100                   65000      65000    65000 65000       65000
                                        2                     2
 100+                     Add 7000mm for every additional 10m floor area

Table B:Total background ventilation (mm2) required for new dwellings with design
air permeability leaker than 5m3 /(h.m2)
                                      Number of bedrooms
 Total floor area (m2)       1         2        3        4        5
 Less 50                     25000     35000    45000 45000       55000
 51-60                       25000     30000    40000 45000       55000
 61-70                       30000     30000    30000 45000       55000
 71-80                       35000     35000    35000 45000       55000
 81-90                       40000     40000    40000 45000       55000
 91-100                      45000     45000    45000 45000       55000
                                         2                      2
 100+                        Add 5000mm for every additional 10m floor area




                                                                                 42
Part G: Sanitation, hot water safety and water efficiency
Sinks with hot and cold running water is to be provided in all food preparation areas,
bathrooms to be fitted with either a bath or shower. Hot & cold water taps to wash basins,
baths, showers & sinks including external taps to have water from a wholesome water
supply. Outlets from domestic hot water storage vessels to be fitted with an in line hot
water supply tempering valve to prevent water temperatures exceeding 60 ºC.

Softened wholesome cold water should not be provided where drinking water is
drawn off or to any sink where food is prepared

The estimated water consumption for new dwellings and flats (including changes of use)
is to be calculated using a ‘Water Efficiency Calculator’ which is to be submitted at the
application stage and approved by building control before works commence on site.
The estimated consumption of wholesome water should not exceed 125 litres per
person/ per day including a fixed factor of water for outdoor use of 5 litres per person/ per
day.

Typical specification for flow rates:
           4/2.6 dual flushing toilets
           All taps fitted with flow regulators to 4 litres per minute
           Shower with flow rates of 6-9 litres per minute
           Standard bath (140 litres capacity to over flow)
           Standard washing machine
           Standard dishwasher

Baths to be fitted with an in line mixing valve to restrict the temperature to 48 degrees C
max

Hot water storage systems to be restricted to 100 degrees C max and outlets from
domestic hot water storage vessels to be fitted with an in line hot water supply tempering
valve to prevent water temperatures exceeding 60 degrees C max.

Hot water storage vessels to be fitted with a non-self-setting energy cut out to instantly
disconnect the power supply.

Wash hand basins to be provided in all rooms containing a w/c and a door must separate
the w/c from any food preparation area in a dwelling

Water tanks/cisterns must have an adequate designed flat platform base to support the
proposed loads.

Pumped small bore foul water drainage from a toilet is only permitted if there is also
access to a gravity draining toilet in the same dwelling. Proprietary pumped foul water
macerator systems must have BBA or other approved accreditation and fitted in
compliance with manufacturers details to a suitable foul water drainage system.

Commissioning certificates for fixed building services are required on completion with
copy sent to building control




                                                                                             43
Part H: Drainage and waste disposal
H1: Foul water drainage
New Foul water connections to the public sewer
Owners of new dwellings are required to consult with the Water Authority and obtain
consent for new foul (& where necessary) surface water connections to the public sewer
before works commence site.

Foul, rain & storm water drainage systems
Both storm and foul drainage to consist of 100mm diameter UPVC proprietary
underground drainage laid at a minimum gradient of 1:40 where serves up to one wc or
1:80 where serves two or more wc’s, surrounded in pea/single size gravel a minimum of
900mm deep in drives and roads and 400mm elsewhere, unless provided with a 100mm
reinforced concrete slab with compressible material under and 300mm min bearing on
original ground.

Proprietary UPVC 450mm diameter inspection chambers to be provided at all changes of
level and or direction and at 45m maximum spacing in straight runs up to 1.2m in depth.
All gullies to be trapped and have rodding access where serving branches. Inspection
chamber covers to be mechanically fixed and suitable for vehicular loads in drives and
roads and proprietary bolt down double sealed covers and frames in buildings.

Foul water to be discharged to new or existing facilities as shown on plans/specification
and storm water from individual down pipes to be piped 5m away from buildings and to
be disposed in a separate surface water sewer via trapped gullies or to soakaways
minimum 2m³ clean filled rubble soakaways per rain water pipe serving a roof area upto
30m2, covered with polythene and top soil or to other methods as shown on the
drawing/specification. Soakaways in clay sub soils or serving roof areas exceeding 30m2
per rwp to be designed in accordance with BRE Digest 365 or by a specialist (i.e.
Hydrologist). Rain/surface water systems cannot be connected to foul water drains
without the written permission of the relevant Water Authority.

Foul drainage systems to low lying buildings or basements which carry storm water or
other vulnerable drainage systems should be provided with anti flood protection such as
one way valves, etc, to prevent flooding and sewerage entering the building.

Waste pipes
All W/Cs to have trapped outlet connected to 100mm diameter pipes, and to be provided,
with a wash hand basin with hot and cold running water. Sanitary appliances such as
wash hand basin, baths, showers, sinks etc, to be provided with 50mm diameter waste
pipes laid to falls and 75mm deep seal traps. Where waste pipe runs exceed 4m BBA
approved air admittance valves are to be fitted above appliance spill over level. Waste
pipes to either discharge below trapped gully grating or into soil and vent pipes via
proprietary waste manifolds or bossed junctions. Internally all waste and drainage pipes
to have rodding access/eyes at changes of direction and be adequately
clipped/supported and provided with 30 minutes fire protection where passing through
floors.




                                                                                       44
H2: Septic tanks, sewage treatment systems & cesspools

Existing septic tank & effluent drainage
Where additional drainage effluent is to be connected to the existing septic
tank/treatment system, it should be checked by specialist and sizes/condition of
tank/system to be confirmed suitable for treatment of additional effluent.

Non mains foul drainage waste water treatment systems
Non mains drainage systems are to be used only where connection to the mains
drainage system is not possible. Either septic tank or sewage treatment system to be
installed as agreed with Building Control to suit specific ground conditions. No septic
tank/ sewage treatment system and associated secondary treatment is permitted by the
Environment Agency in prescribed Zone 1 ground water source protection zones. Where
no other option is feasible, the installation of a cesspool is to be agreed with Building
Control & the Environment Agency.

Septic tanks
Septic tanks to consist of a watertight chamber, water proof from both sides and the
sewage is liquefied by anaerobic bacterial action in the absence of oxygen assisted by
the natural formation of a surface scum or crust. Sludge settlement at the base of the
tank must be removed annually. Discharge from tanks to be taken to drainage fields,
drainage mounds or wetlands/reed beds for secondary treatment as detailed below.

Proprietary factory made septic tanks to be designed and constructed to BS EN 12566
and installed in compliance with manufacturer’s details, or

Non proprietary septic tanks constructed in situ to be designed and constructed to a
drainage specialist’s design, approved by Building Control before the works commence
on site. Typically, the tank consists of two chambers constructed using 150mm minimum
thick concrete base C25P mix to BS 5328, 220mm thick engineering quality brickwork
walls (or concrete), mortar mix 1:3 cement/sand ratio with designed heavy concrete roof
slabs. 100mm diameter Inlet and outlet ‘dip pipes’ designed to prevent disturbance of the
surface scum, inlet pipe laid at a flatter gradient for at least 12 meters before it enters the
tank.

Septic tanks to be fitted with durable lockable lids or covers for emptying and cleaning,
and inspection chamber fitted on the discharge side of tank for sampling of the effluent.

Septic tanks to be sited 7m from any habitable part of any building and preferably
down slopes and have a minimum capacity of 2,700 litres for upto 4 users & increased
by 180 litres for each additional user. (Recommended size of septic tank to be
3,800 litres minimum).

A notice plate must be fixed within the building and include the following information:
Address of the property; location of the treatment system; description of the septic tank
and effluent drainage installed; necessary maintenance to be carried out (including
monthly checks of the apparatus and emptying of the tank every 12 months by a licensed
contractor) and a statement that the owner is legally responsible to ensure that the
system does not cause pollution, health hazard or nuisance.

Consultations are to be carried out with Building Control and The Environment Agency
before any works commence on site. It is the Occupiers responsibility to register the
effluent discharge as an exempt facility with the Environment Agency for discharges of
2m3 or less per day to the ground from a septic tank.
                                                                                             45
 Sewage treatment systems
 Proprietary sewage treatment systems treat sewage by an accelerated process to
 higher standards than that of septic tanks, and are to be factory made, designed and
 constructed to BS EN 12566 (if less than 50 persons otherwise to BS 6297: 1983 Code
of Practice for design and installations of small sewage treatment works and cesspools
and BBA certification or other approved accreditation), installed and maintained in
compliance with the manufactures details and fitted with a uninterruptible power supply
(or 6 hours power back up). Note: only treatment systems suitable for intermittent use
should be used for holiday lets or similar where the system is unused for periods of time.

Sewage treatment system to be sited 7m from any habitable part of any building and
preferably down slopes and have a minimum capacity of 2,700 litres for upto 4 users &
increased by 180 litres for each additional user.

Discharges from sewage treatment systems can be taken to a water course or
alternatively a designed drainage field, drainage mound, wetlands or reed beds as
detailed below.

A notice plate must be fixed within the building and include the following information:
Address of the property; location of the treatment system; description of the sewage
treatment system and effluent drainage installed; necessary maintenance to be carried
out in accordance with the manufacturers details and a statement that the owner is
legally responsible to ensure that the system does not cause pollution, health hazard or
nuisance.

Consultations should be carried out with Building Control and The Environment Agency
before any works commence on site. It is the Occupiers responsibility to register the
effluent discharge as an exempt facility with the Environment Agency for discharges of
5m3 or less per day to a surface water course or 2m3 or less per day to the ground from
a sewage treatment system.

Treatment of sewage from septic tanks & sewage treatment systems

Drainage fields
Drainage fields to consist of irrigation pipes constructed below ground allowing partially
treated effluent to percolate into the ground and further biological treatment in the
aerated soil layers.

 Construction of drainage fields to be carried out as tank/system manufacturers details
 and BS 6297:2007 + A1:2008. See typical section detail and drainage field layout below.
The drainage field area is calculated from the percolation test results which should have
a suggested minimum area of 30m x 0.6m wide subject to percolation test results and
number of users and approved by Building Control before works commence on site. See
below for percolation test procedure.

Drainage fields to be located 10m from any water course, 50m from any point of water
abstraction, 15m from any building & sufficiently far from any other drainage areas so the
overall soakage capacity of the ground is not exceeded. Water supply pipes, access
roads, drives or paved areas etc must not be located within the drainage areas.

Drainage mounds
Drainage mounds to consist of drainage fields constructed above the ground allowing
further biological treatment of the partially treated effluent in the aerated soil layers.
Drainage mounds to be used where there is a high water table level, impervious or semi
                                                                                             46
water logged ground. Drainage mounds and drainage mound areas should be designed
by a drainage specialist for particular ground problems and approved by Building Control
before works commence on site. See diagram 2 of ADH for typical drainage mound
construction details.

Drainage mounds to be located 10m from any water course, 50m from any point of water
abstraction, 15m from any building & sufficiently far from any other drainage areas so the
overall soakage capacity of the ground is not exceeded. Water supply pipes, access
roads, drives or paved areas etc must not be located within the drainage areas.

Wetlands/reed beds
In situations where drainage fields or mounds are not suitable, wetland treatment
systems consisting of manmade reed beds can be constructed as either vertical or
horizontal flow reed bed systems for the purification of the partially treated effluent by
filtration, biological oxidization, sedimentation and chemical precipitation as the partially
treated effluent passes through gravel beds and root systems of wetland plants.
Wetlands should not be constructed in shaded or severe winter areas.

Vertical or horizontal flow wetland treatment systems should be designed by a drainage
specialist for particular ground problems and approved by Building Control before works
commence on site.

A notice plate must be fixed within the building and include the following information:
Address of the property; location of the treatment system; description of the sewage
treatment system and effluent drainage installed; necessary maintenance to be carried
out in accordance with the drainage specialists details and a statement that the owner is
legally responsible to ensure that the system does not cause pollution, health hazard or
nuisance. See diagram 3 of ADH for typical horizontal flow reed bed system and
diagram 4 of ADH for typical vertical flow reed bed system.

Percolation test method to calculate area of drainage field for septic tanks
or sewage treatment systems.
Step 1: Excavate a test hole 300mm square x 300mm deep below proposed invert level
of the drainage field trench bottom
Step 2: Fill the test hole with water and allow drain away over night
Step 3: Refill to a depth of 300mm and note time taken in seconds to drain away
from 75% full to 25% full (i.e. 150mm drop in level from 225mm to 75mm)
Step 4: Repeat the procedure in two more test holes and calculate the average of the
three results as follows: test 1 + test 2+ test 3 = average time taken
                                   3
Step 5: Calculate the Vp (average time in seconds for the water to drop 1mm) as follows:
For example: If average time above took 2100 seconds
(i) Divide 2100 seconds by 150mm depth of water
(ii) 2100 = 14 Vp* (see note below*)
       150
(iii) Area of trench = number of persons to use property X Vp X 0.25
Therefore: 5 persons X 14 X 0.25 = 17.5m2 of effluent drain required.
(iv) To calculate actual length of trench divide 17.5m2 by width of the trench required
therefore: 17.5m2       = 29.16 (Minimum permitted area is 30m long x 0.6m wide)
           0.6m wide

* Vp should range between 12 and 100 to be successful; otherwise the system should be
designed by a drainage specialist.


                                                                                                47
Diagram 14: Typical section through a septic tank/sewage treatment system
drainage field (not to scale)


                     Cross section detail of a septic tank/sewage treatment
                     effluent drainage soakaway trench (not to scale)
                     Ground level

                     Back fill with excavated                                                                Minimum
                     material                                                                                depth 500mm
                     1200g polythene layer

                     100mm diam ridgid Upvc                                                    50mm
                                                                                               100mm diam pipe
                     slotted pipe (slots laid
                     down), laid at 1:200                                                      150mm

                     25-50mm diam clean
                     stone below & covering
                     pipe                                     600 to 900mm
                                                              wide trench, as
                                                              drainage field                      At least 1.0m
                                                              layout below-                       from winter
                                                              minimum 30m                         water table
                                                              length of pipe work                 level



                     Winter water table level




Diagram 14.1 : Typical drainage field plan layout (not to scale)




                                                                                    2000mm min separation
                       Distribution/sampling
                       chamber                              600mm wide trench as
                                                            guidance details


  Inlet


                             2000mm
                             min non
                             slotted                                                100mm diam perforated
                             upvc pipe                      2000mm min separation   effluent distribution pipes
                                                                                    (perforations laid down)
                                                                                    30m minimum length of
                 Septic tank/sewage treatment
                                                                                    rigid upvc pipes
                 plant as guidance details




Note: All effluent drainage pipe work from the tank to be laid at 1:200 gradients etc as guidance details




                                                                                                                           48
H3: Rainwater drainage and harvesting
Rainwater gutters and down pipes
Rainwater gutters and down pipe sizes and number to be suitable for roof area to be
drained in compliance with the table below, and fixed in compliance with manufactures
details. See H3 of ADH for further information



Table 20: Gutter sizes & pipe outlet sizes for drainage of roof areas
       Max effective roof area m2 Gutter sizes (mm        Outlet sizes (mm diam)
                                    diam)
       18.0                         75                    50
       37.0                         100                   63
       53.0                         115                   63
       65.0                         125                   75
       103.0                        150                   89
      The sizes above refer to half round gutters & round rain water pipes

Rainwater/ grey water harvesting storage tanks & systems
Rainwater harvesting system to be designed, supplied, installed, and commissioned by
specialist to supply rainwater to sanitary appliances. Below drainage pipework as foul
water pipe guidance details above.

Grey water systems designed for use within the building is to be designed,
manufactured, installed and commissioned by a suitably qualified and experienced
specialist. Grey water to be treated prior to use in toilets etc by an approved method.

Overflow from the rain water storage tank is to discharge to a designed soakaway system
constructed 5m from any building & septic tank soakaway system.

Grey water & rainwater tanks & systems should:
    Prevent leakage of the contents, ingress of subsoil water & should be ventilated
    Have an anti backflow device on any overflow connected to a drain or sewer
    Have a corrosion proof locked access cover for emptying & cleaning
      Supply pipes from the grey water or rain water collector tanks to the dwelling must
      be clearly marked as either ‘GREY WATER’ or ‘RAIN WATER’.
    Guidance should be followed in par 1.69-1.72 of App Doc H2, App Doc G of the
      Building Regulations and the Water Regulations Advisory Scheme Leaflet No: 09-
      02-04, and BS 8515:2009.

Surface water drainage around the building
Paths and paved areas around the building to have a non slip finish and if not porous
propriety design to be provided with a cross fall of 1:40 – 1:60 and a reverse gradient of
at least 500mm away from walls of building. Surface water to be disposed of by an
adequately sized and roddable drainage system via soakaways, or other approved
means.




                                                                                             49
Oil/fuel separators
Under section 111 (restrictions on use of public sewers) of The Water Industries Act
1991, it is an offence to discharge fuels into water courses, coastal water or underground
water. Oil separators are required where fuel is stored or in other high risk areas or car
parks and the Environment agency has issued guidance on the provision of oil
separators.

For paved areas around buildings or car parks a bypass separator is required with a
nominal size (NSB) of 0.0018 times the contributing area and silt storage area (in litres)
equal to 100 times the NSB.

In fuel storage areas and other high risk areas full retention separators are required with
a nominal size (NS) equal to 0.018 times the contributing area and silt storage area (in
litres) equal to 100 times the NS.

Separators discharging to infiltration devices or surface water sewers should be class 1

Proprietary oil separators should be, factory made, water proof, designed and
constructed to the requirements of the Environment Agency, licensing authorities
requirements (where the Petroleum Act applies), prEN858 and BBA certification or other
approved accreditation. Separators must be installed and maintained in compliance with
the manufacturers details and inlet arrangements should not be direct to the water
surface, and adequate ventilation must be provided. See Appendix H3 -A of ADH3 for
further information

H4: Building over or close to public sewers
Owners of building being constructed, extended or underpinned within 3m of a public
sewer as indicated on the relevant Water Authorities sewer maps are required to consult
with the Water Authority and where necessary obtain consent and enter into an
agreement to build close to or over the public sewer before works commence site.

Protection of the sewer pipe and systems are to be carried out in compliance with the
relevant Water Authorities requirements.

As part of this process, building control will check the proposed development against the
relevant Water Authorities sewer maps regarding building over/close to the public sewer
and where necessary building control will consult with the Water Authority and request
that they send any comments directly to the building owner/agent within 14 days of the
consultation. Building notices are not acceptable where an agreement is required to
building close to or over a public sewer and full plans applications will be required. See
H4 of ADH for further information

H5: Separate systems of drainage
The building owner/agent must carry out all necessary consultations with the
relevant Water Authority before works commence on site. Rain/surface water systems
cannot be connected to foul water drains without the written permission of the relevant
Water Authority. See H5 of ADH for further information.

H6: Solid waste storage
1200 X 1200mm level paved areas are required beside rear access for refuse storage
containers or alternatively a communal storage area can be provided for a wheelie bin
suitable to store 0.25m3 minimum per dwelling subject to approval from the waste
collection authority.

                                                                                             50
Part J: Combustion appliances & fuel storage systems
Space & hot water heat producing appliances in general
Space and hot water heating method as detailed on the plans/specification. Heating to be
supplied from new or extended gas/LPG/oil fired wall/floor mounted condensing balanced
flue boiler with the flue discharging 600mm minimum away from openings into the
building and protected with a proprietary wire basket to boiler manufacturers
specification.

Boilers to have a SEDBUK efficiency above 90% to comply with Building Regulations as
amended in October 2010 for gas/ LPG/oil and must be provided with separate controls
for heating and hot water with a boiler interlock, timer, and thermostat radiator valves to
each room. Un-vented hot water systems require safety devices including non self setting
energy cut out & temperature release valve and thermostat. Safety valves from vented
hot water systems must discharge safely.

Hot water vessels to be insulated with 35mm minimum thickness of PU foam and both
heating and water pipes to be insulated with proprietary foam covers equal to their
outside diameter within 1m of the vessel and in unheated areas. Hot water storage must
not exceed a temperature of 100 degrees centigrade.

Gas installations to be installed and comply with BS 5440, BS 5546, BS 5864, BS5871,
BS 6172, BS 6173 and BS 6798.

Oil installations to be installed and comply with BS 5410, BS 799.

All space and hot water systems must be installed, commissioned, calibrated and
certified by a suitably qualified person or installer registered with an appropriate
competent persons scheme and details supplied to Building Control and the owner along
with the operating manuals, etc before the building is completed/occupied.

Solid fuel appliances up to 50kW rated output
Construction of open fire place with recess & hearth
Fire place walls to consist of non combustible material of at least 200mm in thickness to
the side 100mm thick in the back wall recess, lined with suitable fire bricks. The hearth to
be at least 125mm thickness (or 12mm thick if provided over a concrete floor slab) of non
combustible materials with projections at least 150mm to the sides of the side jambs and
500mm in front of the jambs.

Free standing stove with hearth
Free standing stoves & hearths to be positioned 150mm minimum away from enclosing
non combustible walls at least 100mm thick. Hearths to be at least 125mm thickness (or
12mm thick if provided over a 100mm thick concrete floor slab),constructed of non
combustible materials with projections at least 150mm to the sides & rear of the
appliance and 300mm in front of the appliance door.

Air supply (ventilation) to solid fuel appliances
Permanently open combustion air vents ducted to outside are to be provided in the same
room as the solid fuel appliance with a total free area in compliance with the table below
(see Table 1 of ADJ for further information)




                                                                                          51
Table 21: Air supply (ventilation) to solid fuel appliances
Type of appliance                            Amount of ventilation
Open fire place with no throat (i.e. under a 50% of the cross section area of the
Canopy)                                      Flue

Open fire place with throat                   50% of the cross section area of the
                                              Throat opening area
or for simple fire openings:
                    500mm wide                20,500mm2
                    450mm wide                18,500mm2
                    400mm wide                16,500mm2
                    350mm wide                14,500mm2
Enclosed stove with flue draught stabilizer
In new dwellings                              850mm2/kW of appliance rated out put


Enclosed stove with no flue draught
stabilizer In new dwellings                   550mm2/kW of appliance rated out put



Carbon monoxide alarms
Mains operated carbon monoxide alarm is required at ceiling level in the same
room as the solid fuel appliance, which must be either battery operated in
compliance with BS EN 5029: 2001: or mains operated with sensor failure
warning device in compliance with BS EN 5029: Type A

Carbon monoxide alarm to be positioned on the ceiling at least 300mm from
walls, or if located on the wall as high up as possible (above any doors or
windows) but not within 150mm of the ceiling, and between 1m and 3m
horizontally from the appliance

Table 22: Sizes of flues in chimneys
Installation                                  Minimum internal flue sizes
Fire place with opening up to 500 x 500mm     200mm (diameter, rectangular or square)
Fire place with opening more than 500 x       Area equal to 15% of the total face area of
500mm or exposed on both sides                the fireplace opening. (note: total face
                                              areas more than 15% or 0.12m2 to be
                                              designed by heating specialist)
Closed appliances* (stove, cooker, room       (diameter, rectangular or square)
heater & boiler) up to 30kW rated output      150mm
                   30- 50kW rated output      175mm
Closed appliances up to 20kW rated output     See table 2 of ADJ
which-burns smokeless/low-volatile fuel, or
complies to the Clean Air Act
Pellet burner which compiles to the Clean     See table 2 of ADJ
Air Act




                                                                                        52
Construction of masonry chimneys
Chimneys to be constructed in external quality frost resistant materials 100mm minimum
thickness (increased to 200mm where separates another fire compartment or another
dwelling), using brick, dense blocks or reconstituted/natural stone to match the existing,
with suitable mortar joints for the masonry as the masonry manufacturers details with any
combustible material kept at least 50mm away from the walls containing flues.
Line chimney with manufactured flue liners installed in compliance with manufacturers
details as follows:

(i) Clay flue liners to BS EN 1457:2009: Class A1 N1 or Class A1 N2, to be laid vertically
and continuously socket up (jointed with fire proof mortar) from appliance with a
minimum diameter in compliance with table 22
(ii) Concrete flue liners to BS EN 1857:2003: Type A1, A2, B1 or B2 to be laid vertically
and continuously socket up (jointed with fire proof mortar) from appliance with a
minimum diameter in compliance with table 22
(iii) Liners whose performance complies to BS EN 1443:2003: designation: T400 N2 D 3
G with a minimum diameter in compliance with table 22

Backfill gaps between masonry and flue liners with a weak mix concrete using 1:6
ordinary Portland cement and vermiculite. Build in code 5 lead flashings (including apron
& lay board flashings) & dpc tray into chimney as work proceeds, 150mm above all
roof/wall abutments as necessary & terminate chimney with a proprietary chimney pot to
match the internal flue sizes.

Construction of factory made flue block chimneys
Construction of factory made flue block chimneys are to be carried out in compliance with
paragraphs 1.29 – 1.30 of ADJ, and appliance manufacturer’s details.

Construction of factory made metal chimneys
Construction of factory made metal chimneys are to be carried out in compliance with
paragraphs 1.42 – 1.46 of ADJ, and appliance manufacturer’s details. Factory made
metal chimneys are to be concealed in the building in compliance with paragraph 1.47 &
diagrams 13 & 14 of ADJ.

Configuration of flues serving open flue appliances
Flues to be constructed straight and vertical with no more than a 90 degree bend with
cleaning access where the flue connects to the appliance and no more than two 45
degree bends (to the vertical) in the flue configuration in compliance with paragraph
1.48- 1.49 of ADJ, .

Inspection & cleaning openings in flues
Inspection & cleaning openings should be air tight using proprietary factory made
components compatible with the flue system, fitted & located to allow sweeping of the
flue in compliance with appliance manufacturers details

Interaction of mechanical extract vents & opened flue solid fuel appliances
Where a kitchen contains an opened flue- solid fuel appliance, confirm extract
ventilation will not be installed in the same room as the appliance, or alternatively seek
further guidance from HETAS.




                                                                                             53
Chimney heights
Chimney height not to exceed 4.5 times its narrowest thickness. Chimney/terminal to
discharge at a minimum height of:

      1.0m above flat roofs
      1.0m above opening windows or roof lights in the roof surface
      0.6m above the ridge
      Outside of a zone measured 2.3m horizontally from the roof slope
      0.6m above an adjoining or adjacent building that is within 2.3m measured
       horizontally (whether or not beyond the boundary)

Please refer to Diagram 17 of ADJ for full details

Alternative heating producing appliances as detailed on the drawing/specification to be in
compliance with ADJ.

Repair/relining of existing flues
Repair /relining of existing flues to be carried out by a suitably qualified and experienced
specialist. Re-use of existing flues to be inspected, tested and certified by a suitably
qualified and experienced specialist prior to use as suitable for solid fuel appliances.

Relining of existing flues to be carried out in compliance with BS EN 1443:2003:
designation: T400 N2 D 3 G with minimum diameters in compliance with table 22 using
lining systems suitable for solid fuel appliances as follows:

(i) Factory made flue lining systems in compliance with BS EN 1856-1:2003 or BS EN
1856-2:2004
(ii) Cast in-situ flue lining system in compliance with BS EN 1857:2003+A1:2008

Notice plates for hearths & flues
Notice plates for hearths & flues should be permanently displayed next to the flue (or
electricity consumer unit or water stop tap) detailing the property address; location of
installation (room); type of installation the flue is suitable for; size & construction of flue, if
suitable for condensing appliance, installation date, and any other information (optional).

Appliances other than solid fuel

Interaction of mechanical extract vents & opened flue combustion appliances
Gas appliances
Where a kitchen contains an opened flue- gas appliance, the extract rate of the kitchen fan
should not exceed 20 l/s (72m3/hour) and the appliance should be tested and certificated by a
suitably qualified and registered gas engineer that the combustion appliance operates safely
whether or not the fans are running.

Oil appliances
Where a room contains an opened flue- oil appliance, the extract rate of the fan should not
exceed 40 l/s for an appliance with a pressure jet burner and 20l/s for an appliance with a
vaporising burner.

Gas heating appliances up to 70kw
Gas burning appliances up to 70kW to be installed, commissioned and tested in
compliance with section 3 of ADJ, and the Gas Safety (installation & use) Regulations.
All works to be to be carried out by an installer registered with Gas Safe. Copy of
commissioning certificates to be issued to Building Control on completion of the works.
                                                                                                 54
Oil heating appliances up to 45kW
Oil burning appliances up to 45kW to be installed, commissioned and tested in
compliance with section 4 of ADJ. All works to be to be carried out by an installer
registered with OFTEC. Copy of commissioning certificates to be issued to Building
Control on completion of the works.

Renewable energy Installations
Renewable energy systems must be installed, commissioned, calibrated and certified by
a suitably qualified person or specialist installer registered with an appropriate competent
persons scheme (where applicable) and details supplied to Building Control and the
Owner along with the operating manuals, etc for the following installations:
    Solar photovoltaic (pv) roof/wall panels for producing electricity
    Biomass space heating & hot water systems
    Wind energy turbines for producing electricity
    Hydro-power systems for producing electricity
    Solar water heating roof/wall panel systems, fitted with an additional heating
       source to maintain an adequate water temperature
    Ground/air source heat pumps for space heating & hot water systems

All roof / wall structures must be adequate to support the above installations in
compliance with manufacturers details or calculations & details from a suitably qualified
person which must be approved by Building Control before works commence on site.

Provision of information- commissioning certificates (testing)
Copy of installers commissioning certificate to be sent to building control on completion
of the work.

Fuel storage tanks
LPG tanks and cylinders up to 1.1 tonnes
LPG tanks and cylinders up to 1.1 tonnes to be positioned in the open air at least 3m
from buildings or boundaries. LPG cylinders to be positioned in the open air on a
minimum 50mm thick concrete base, securely chained to the wall and positioned at least
250mm below and 1m from any openings horizontally into the building such as windows,
combustion, vents or flue terminals and 2m from un-trapped drains or cellar entrances.

Oil tanks up to 3500 litres
Oil tanks up to 3500 litres to be positioned in the open air on a concrete base with a
minimum thickness of 50mm extending a minimum of 300mm beyond the tank base and
be positioned a minimum of 1.8m from buildings or flues and 760mm from boundaries.
They should also be provided with a proprietary fire resistant pipe and valve system.
Where there is a risk of pollution to water courses, open drains including inspection
chambers with loose covers, the tank should be either internally bunded or be provided
with an impervious masonry bund equal to capacity of 110% of its volume. Where any of
the above requirements cannot be met- please contact building control for further
guidance.




                                                                                            55
Part K: Protection from falling, collision and impact
Internal stairs, landings and changes in level of 600mm or more
Stairs to be constructed (and finished) in materials to Clients choice to BS 5395 &
BS 585 as detailed below:- (Spiral & helical stairs to be designed to BS 5395: Part 2)

Stair pitch not to exceed 42° and design to be based upon dimensions taken from site
and drawing.

Rise and going to be level and equal to all steps and to fall within the following separate
classes:-
    Any rise between 155mm-220mm used with any going between 245mm- 260mm,
      or
    Any rise between 165mm-200mm used with any going between 223mm- 300mm.

(Twice the rise plus the going must be between 550 & 700mm)

Diagram 15: Measuring rise & goings (not to scale)

                                   tread


                      open riser           nosing
                                                       top surface of tread
               Note: treads                                rise
                                      riser
               should over lap at                                   top surface of tread
               least 16mm

               Note: going dimention to
               be measured from nosing
               to nosing
                                               going




                                                                                           `
Stair to have a minimum headroom of 2000mm above stair pitch line and to be provided
with landings clear of any door swing top and bottom equal in length to the width of the
stairs. If doors open across a bottom of a landing- a clear 400mm space must be
maintained across the width of the flight. Minimum stair width for new dwellings is
900mm in the entrance storey suitable for disabled persons.

Handrails must be provided on both sides of the stairs, at a height 900-1000mm above
floor/nosing levels and continuous throughout their length suitable for disabled persons.

All guarding is to be at a minimum height 900mm above floor/nosing levels and
continuous throughout their length, with non climbable vertical balustrading, no gaps to
exceeding 100mm and all constructed to resist a horizontal force of 0.36kn/m. All open
treads, gaps etc should not exceed 100mm.

Typical staircase construction details: side strings ex. 230 X 35mm, capping ex. 32 X
63mm, treads 25mm thick, risers in 12.5mm thick plywood, newel posts ex. 75 X 75mm,
handrails ex. 75 X 63mm, balustrades ex. 32 X 32mm at 125mm ctrs fixed into
proprietary timber head & base rebated capping.



                                                                                               56
Diagram 16: Typical internal stair case & guarding construction details
(not to scale)

     At least 2000mm clear head
     room (can be reduced to
     1900mm at the centre of the
     stairs & 1800mm at the side in
     loft conversions)




         Handrail & guarding          Newel
                                      post     Handrail & guarding
         at least 900mm high
                                                at least 900mm high
         above landing level
                                                   above pitch line

                                                      non climable balustrades
                                                      & no gaps to exceed
                                                      100mm

                                                              All guarding must
                                                               resist a horizontal
                                                                      force of
                                                                       0.36kn/m
                trimmer joists
                                                                                               At least 2000mm clear
                                                                                               head room (can be
                   Landing
                                                                                               reduced to 1900mm at the
                 Landings must                                                                 centre of the stairs &
                 be level &                                                                    1800mm at the side in loft
                 equal in                                                                      conversions)
                                              tread
                 length to the
                                                                             pitch line
                 smallest width

                Note: No opening to                    rise
                allow the passage of
                100mm diam sphere                             outer string


                                                                                 Max
                                                                               42 degree
                                                                                pitch
                                                  Flight                                            Landing



                                                                                 Note: Landings to be clear of any
                                                                                 obstructions. A door may swing accross a
                                                                                 landing at the bottom of a flight but must
                                                                                 allow a 400mm min clear space accross the
                                                                                 full width of the flight clear of any door
                                                                                 swing



External stairs, landings and changes in level of 600mm or more
External stairs & landings
As internal stair guidance details above

External guarding
Guarding to external stepped access/openings/balconies to be at least 1100mm high
provided with non climbable vertical balustrading, with no gaps exceeding 100mm and
constructed to resist a horizontal force of 0.74kn/m. All open treads, gaps etc should not
exceed100mm.

Guarding to upper storey window openings/other openings within 800mm of floor
level
Opening windows located above the ground floor storey with openings within 800mm of
floor level must be provided with non climbable containment/guarding or proprietary
catches which should all be removable (but child proof) to means of escape windows in
the event of a fire. All gaps etc to containment/guarding should not exceed 100mm.


                                                                                                                              57
Part L: Conservation of fuel and power in new dwellings

Target & dwelling emissions rates
Target Emissions Rate (TER) and a design Dwelling Emissions Rate (DER) to be
provided in compliance with SAP 2009 and ADL1A as soon as possible and before
works commence on site.

Sap rating & energy performance certificate
As built SAP rating (or design SAP rating if the construction details are unchanged)
& registered energy performance certificate to be provided in compliance with SAP
2009 and ADL1A, within 5 days prior to completion.

Building control can provide a target and dwelling emission rate, SAP rating &
registered energy performance certificate in compliance with SAP 2009 if required,
please contact Building Control on 01594 810000 for more information.

Fabric standards (worst acceptable standards)
Thermal insulation standards in new dwelling to be in compliance with paragraphs
4.18 - 4.24 and worst acceptable standards in compliance with table 2 of AD L1A as
follows:

Roof:                       U-value 0.20 W/m2.K
Walls:                      U-value 0.30 W/m2.K
Floor:                      U-value 0.25 W/m2.K
Party wall:                 U-value 0.20 W/m2.K
Windows, roof lights,
doors & curtain walling :   U-value 2.00 W/m2.K
Air permeability:           10.00 m3/h.m2 at 50pa

Recommended starting u values
Thermal insulation standards have been indicated in this guidance to achieve the
following starting point U values:

All roof types:             U-value 0.13 W/m2.K
Walls:                      U-value 0.18 W/m2.K
Floors:                     U-value 0.13 W/m2.K

U values for party walls
Party walls U values to be in compliance with table 3 of AD L1A as follows:

Solid walls:                                      U-value 0.0 W/m2.K
Unfilled cavity with effective edge sealing:      U-value 0.2 W/m2.K
filled cavity with effective edge sealing:        U-value 0.0 W/m2.K
Note: Unfilled cavity with no effective edge sealing will not achieve the minimum
required worst case U-value of 0.2 W/m2.K




                                                                                       58
Energy efficient lighting
Fixed internal & external energy efficient lighting systems to be provided in
compliance with paragraph 4.13 of ADL1A as follows:

Fixed internal lighting
Fixed internal energy efficient lighting in new dwelling will be at least 75% of all
the fixed low energy light fittings (fixed lights or lighting units) in the main dwelling
spaces (excluding cupboards & storage areas), fitted with lamps which must have a
luminous efficiency greater than 40 lumens per circuit-watt and a total output greater
than 400 lamp lumens. (note: light fittings with less than 5 circuit-watts are excluded)

Fixed external lighting
Fixed external energy efficient lighting in new dwelling will consisting of either;
       (i) Lamp capacity not greater than 100 lamp-watts per light fitting and fitted with
       automatic movement detecting control devices (PIR) and automatic daylight cut-off
       sensors; or
       (ii) Lamp efficacy greater than 45 lumens per circuit-watt; and fitted with automatic
       daylight cut-off sensors and manual controls.

Limiting the effects of solar heat gains in summer
Details of measures taken to limit solar gains to be provided in energy assessment in
compliance with paragraphs 4.25-4.27 of ADL1

Limiting thermal bridging around external openings
Thermal bridging around external openings will be provided in compliance with
paragraphs 5.9- 5.13 of ADL1A as follows:

       (i) Adopt a quality- assured accredited construction detail approach
       approved by the Secretary of State and the calculated linear thermal
       transmittance can be used directly in the DER calculation in compliance with
       paragraph 5.12 a.

       (ii) Use non- assessed details in compliance with BRE Report BR 497
       Conventions for Calculating Linear Thermal Transmittance and Temperature
       Factors 2007, (ISB N 978 1 86081 986 5) and the increased calculated values can
       be used in the DER calculations, in compliance with paragraph 5.12 b.

       (iii) Use unaccredited details with no specific quantification of the thermal bridge
       values. In such cases a conservative default y- value of 0.15 must be used in the
       DER calculation in compliance with paragraph 5.12 c.

Air permeability & pressure testing
Limiting air leakage
Air leakage will be limited in the new dwelling fabric as indicated on plan layouts/
section details in compliance ADL1A and Accredited Construction Details (see
information available from: www.planningportal.gov.uk)

All external door and window frames, service penetrations to walls, floors, joists and
ceilings, etc, should be sealed both internally and externally with proprietary sealing
products such as proprietary waterproof mastic, expanding foam or mineral wool or tape
to ensure air tightness.


                                                                                              59
Pressure testing of new dwellings
Where required by the SAP rating, pressure testing will be carried out by a specialist
registered by the British Institute of Non-destructive Testing in compliance with the
TER design limits in compliance with paragraphs 5.14- 5.22. Test results to be
provided by specialist and copy sent to Building Control within 7 days after test
carried out.

Building control can provide pressure testing if required, please contact Building
Control on 01594 810000 for more information.

Pressure testing will be carried out on three units of each dwelling type or 50% of
all instances of that dwelling type, whichever is the less in compliance with
paragraph 5.18 of ADL1A.

Alternative to pressure testing
Alternative to pressure testing on small sites of less than two dwellings to be erected:

       (i) Confirm with test results that a same dwelling type has been constructed by the
       same developer within the last 12 months and has achieved the required design
       air permeability in compliance with paragraph 5.14- 5.18 of ADL1A.
       or
       (ii) To avoid the need for any pressure testing by using a value of 15m 3/(h.m2) at
       50Pa for the air permeability when calculating the DER.

Providing information
The following information will be provided in the new dwelling on completion in
compliance with paragraphs 6.1- 6.4 of ADL1A:
           Operating & maintenance instructions for fixed building services
           Instructions how to make adjustments to timing and temperature
       control settings etc
           Instructions on routine maintenance requirements for fixed building services
              in compliance with manufacturers details
           Energy assessment data used to calculate the TER & DER and the as built
              Energy Performance Certificate




                                                                                           60
Part M: Access to and use of buildings for disabled
External ramped approach
A level/ramped approach with a firm hard non slip surface at least 900mm wide is to be
provided from a vehicular parking area or the street/road not steeper than 1:15 with 1.2m
landings every 10m or 1:12 with landings every 5m both with top and bottom landings at
least 1.2m clear of a door swing up to the principal entrance door.

External Stepped approach
Sites with a slope of more than 1:15 may be provided with a stepped approach as
follows:
     An unobstructed width of at least 900mm with a firm hard non slip
      surface to all steps and landings
     Landings to be provided at the top & bottom of the steps at least 900mm
      long
     The rise of a flight must not exceed 1.8m between landings
     Steps to have a suitable tread nosing profile and uniform rise between
      75-150mm and a uniform going of 280mm (which for tapered treads should be
      measured at a point 270mm from the inside of the tread).
     Where there are 3 or more risers, a continuous handrail is to be
      provided on one side of the flight with a grippable profile fixed 850-
      1000mm above the step pitch line and extending 300mm beyond the top & bottom
      nosings.
Even when a stepped approach is used, an accessible or level threshold as describe
below should be provided. If a step is unavoidable, the rise should not exceed 150mm.

Accessible level door thresholds into the building
Level landings should be provided at the same level as the entrance door thresholds with
a fall of 1:40 –1:60 away from the door separated from the building by proprietary tanking
and a proprietary drained channel or 25mm max drainage slot- linked into the storm
water drainage system.

The door threshold should have a maximum 15º slope into the drainage channel/slot and
provided with a proprietary raised threshold storm proof weather seal which should not
exceed 15mm high (any projection more than 5mm should have chamfered or rounded
edges) to allow safe unobstructed wheel chair access into the building
.
External door opening widths
The external principal entrance door should have a minimum clear opening between the
door leaf and doorstops of 775mm.

Internal passageways/corridors widths
Internal passageways/corridors should have minimum widths as set out in the table
below:
  Doorway clear opening          Corridor/passageway width*
  width mm                       mm
  750 mm or wider                900 mm (when approached head on)
  750 mm                         1200 mm (when not approached head on)
  775 mm                         1050 mm (when not approached head on)
  800 mm                         900 mm (when not approached head on)
* Note: A corridor width of 750mm min is acceptable where there is a permanent
obstruction not exceeding 2.0m in length, e.g. radiator or similar providing the obstruction
it is not placed opposite a door that would prevent a wheel chair user turning.

                                                                                          61
Internal stairs
Minimum stair width for new dwellings is 900mm in the entrance storey suitable for
disabled persons.

Handrails must be provided on both sides of the stairs, at a height 900-1000mm above
floor/nosing levels and continuous throughout their length suitable for disabled persons.

Stairs, landings & guarding to be compliance with Part K of this guidance

Accessible switches, sockets, controls etc
All switches and sockets including the consumer unit, ventilation & service controls, door
bells, entry phones, telephone points & tv/computer sockets etc, should be fixed between
450-1200mm above floor level. Accessible consumer units should be fitted with a child
proof cover or installed in a lockable cupboard.

Provision of a ground floor W/C
A W/C must be provided on the principal entrance storey with an outward opening door
conforming to the above widths. The W/C enclosure/position should have a clear space
of at least 450mm each side of the centre of the W/C with a clear space of at least
750mm in front of the W/C pan to allow a wheelchair to approach within 400mm of the
W/C from the front or within 250mm of the front of the W/C pan from the side. The
washbasin is to be positioned not to impede access and the spaces outlined above.




                                                                                            62
Part N: Safety glazing, opening & cleaning
Safety glass and glazing
Doors and adjacent sidelights/windows in critical locations within 1500mm of ground and
floor level, and 300mm of doors and windows within 800mm of floor/ground to be safety
glazed to: BS EN 12150, BS EN 14179, BS EN 14449, which supersedes BS 6206 in
compliance with the following diagram:

Diagram 17: Glazing in windows, partitions, doors, side panels/screens & walls




Safety glazing must comply with the new system of marking which requires visible and
clear and indelible markings on each piece of safety glazing within critical locations in
compliance with: BS EN 12150, BS EN 14179, BS EN 14449




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Part P: Electrical safety
Electrical Installations
New or works to existing electrical circuits or systems must be designed, installed, tested
and certified to BS 7671 or with the current editions of the IEE regulations by a
competent person in compliance with Approved Document P of the Building Regulations.

A competent electrician or a member of a competent person scheme must test and
certify all such works. The electrician must provide signed copies of an electrical
installation certificate conforming to BS 7671 for the owner of the property and a copy
must be forwarded to the Building Control surveyor for approval at completion, so the
Building Control completion certificate can be issued.

All switches and sockets including the consumer unit, ventilation & service controls etc,
should be fixed between 450-1200mm above floor level. Accessible consumer units
should be fitted with a child proof cover or installed in a lockable cupboard.




                                                                                            64
External works- paths, drives, patio & gardens
New external paths to be shuttered 100mm thick conc. Mix type PAV 1, max bay size 6m
with bitumen impregnated fiber board isolated Joints to BS 8110/5328 .

New tarmac areas to be rolled 20mm base course of coated macadam with 6mm
textured bitumen macadam wearing course with concrete edgings, to BS4987.

New 60mm pre-cast self draining concrete block paving to clients choice, laid in
compliance with manufacturers details, to BS6717.

Concrete/natural stone slabs to clients choice, laid in compliance with manufacturers
details to BS 7263:1

Drainage of paved areas to be carried out in accordance with BS 6367:1983 A1 84
and Approved Document H. Paths and paved areas to have a non slip finish with a fall of
1:80 and a reverse gradient of at least 500mm away from walls of building. Surface water
to be disposed of by an adequately sized and roddable drainage system via soakaways,
or other approved means.




                                                                                        65
Materials and workmanship
All materials must comply with the following:
     British Standards or European Standards
     Product Certification Schemes (Kite marks)
     Quality Assurance Schemes
     British Board of Agreement Certificates (BBA)
     Construction Product Directives (CE Marks)
     Local Authority National Type Approvals (System Approval Certification)

All materials must be fixed in strict accordance with manufacturers printed details and
workmanship must be in strict accordance with BS 8000: Workmanship on Building Sites:
Parts: 1 to 16. Where materials, products and workmanship are not fully specified or
described, they are to be: Suitable for the purpose stated or inferred & In accordance
with recognized good practice


Guidance notes copyright
Guidance notes copyright & produced by: Tony Gwynne, Forest of Dean District Council,
Council Offices, High Street, Coleford, GL16 8HG. Tel: 01594 810000,
Website: www.fdean.gov.uk        E mail: building.control@fdean.gov.uk

Acknowledgements:
Front cover illustration by Apex Architecture Consultancy: 01594 516161
Information for domestic sprinklers by Nationwide Fire Sprinklers Ltd: 0115 987 1110

Important note:
It should be made clear that whilst every care has been taken to in compiling this
publication, and the statements it contains, no party or individual involved in this
publication can accept any responsibilities for any inaccuracies.

Additional building control services we can provide
Building control can now provide the following services and manage them through your
project as part of the service we offer:

   o SAP Calculations: Design Stage Calculations includes Residential Energy Performance
       Certificate and registration of certificate on completion.
   o Air Leakage Testing ( Residential & commercial)
   o SBEM Calculations
   o Code for Sustainable Homes Assessments
   o Renewable Energy Evaluations/Payback Reports etc
   o Fire Risk Assessments

For more information, please contact Tony Gwynne, Mark Saunders or Simon Drake on
01594 810000




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For further advice on Building Regulation issues in Gloucestershire
please contact your local Building Control Service:

          Cheltenham and Tewkesbury Building Control Service
          Cheltenham Office: Municipal Offices, Promenade, Cheltenham, GL50 9SA
          Tel: 01242 264321         Fax: 01242 227323       Email: buildingcontrol@cheltenham.gov.uk



          Cotswold District Council
          Building Control, Trinity Road, Cirencester, GL7 1PX
          Tel: 01285 623000         Fax: 01285 653905 Email: building_control@cotswold.gov.uk



          Forest of Dean District Council
          Building Control Services, Council Offices, High Street, Coleford, GL16 8HG
          Tel: 01594 810000         Fax: 01594 812353       Email: building.control@fdean.gov.uk

          Gloucester City Council
                              th
          Building Control, 4 Floor, Herbert Warehouse, The Docks, Gloucester, GL1 2EQ Tel: 01452 396771
                          Fax: 01452 396763         Email: buildingcontrol@gloucester.gov.uk

          Stroud District Council
          Building Control Services, Ebley Mill, Westward Road, Stroud, GL5 4UB
          Tel: 01453 754518         Fax: 01453 754511       Email: building.control@stroud.gov.uk



Useful numbers of other agencies or companies
Forestry Commission                   01594 833057
Sewage & Water Suppliers:
Severn Trent Water                    0800 783 4444
Welsh Water/Dwr Cymru                 0800 085 3968
Environment Agency                    08708 506 506
Emergency Pollution Hot Line          0800 80 70 60
Transco Gas Emergencies               0800 111 999
Health & Safety Executive             01179 88 60 00

Gloucestershire County Council
General Enquiries            01452 425000
Gloucestershire Fire &
Rescue Service               01452 753333
Highways Agency              0845 9 55 65 75

(Amended Oct 2010 - Tony Gwynne)




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