; Heritage conservation and adaptive reuse of buildings
Documents
Resources
Learning Center
Upload
Plans & pricing Sign in
Sign Out
Your Federal Quarterly Tax Payments are due April 15th Get Help Now >>

Heritage conservation and adaptive reuse of buildings

VIEWS: 2,259 PAGES: 17

www.seminarsview.blogspot.com

More Info
  • pg 1
									HERITAGE
CONSERVATION AND
ADAPTIVE REUSE OF
BUILDINGS




               [2010]
                                     CONTENTS



1.0 Introduction                                                    1
2.0 Conservation                                                    2
    2.1 Conservation In India                                       3
3.0 Conservation Of Structures                                      3
    3.1 Structural Monitoring                                       4
    3.2 Factors Causing Deterioration Of Structural Element         4
    3.3 Preparatory Works Before Conservation                       5
    3.4 Washing Techniques                                          6
    3.5 Technical Consolidation To Arrest Decay Of Stones           8
    3.6 Dealing With Old Mortars                                    9
4.0 Adaptive Reuse                                                  11
    4.1 What Is Adaptive Reuse?                                     11
   4.2 Adaptive Reuse In India                                      11
   4.3 Economic Profile Feasibility Study                           12
   4.4 Adaptive Reuse Conversions Of Non-Residential Buildings To
      Residential Buildings – Case Study                            12
5.0 Conclusion                                                      14
   Acknowledgement                                                  14

   References                                                       15




                                             1
HERITAGE CONSERVATION AND ADAPTIVE REUSE OF
BUILDINGS


Keywords: Conservation, Adaptive Reuse, Heritage


1.0 INTRODUCTION
        There was a time when words like preservation, conservation and heritage in architecture
were considered as a curse to the progress of developing nations. New flashy high-rise structures
were built. These were often built on the arches of the old structures that were the last traces of a
culture threatened with extinction. The past it was ostensibly argued was relevant only if the
future was more certain.
        Conservation depicts restoration of the past and preservation of future. These are certain
structures to which members of society feel attached with the sense of belonging and they have
more than one reason to insist on their conservation. Conservation is the most important
engineering understanding to develop the observational exposure so as to decide when not to
touch the structure and leave it to itself.




Undergraduate Student, Department of Civil Engineering, NSS College of Engineering,
Palakkad-8, Kerala




        The deterioration of a building may be structurally or functionally.              Structural
deterioration includes the damages caused on the building load carrying elements such as beams,
walls etc. Functional deterioration may be resulted from environmental reasons like chemical
action on buildings etc.       In this paper some measures to conserve the buildings from
environmental deterioration are included.


2.0 CONSERVATION


                                                 2
        Conservation is the process by which we can maintain and retain our culture, tradition
and environment, ecology systems, art, architecture etc. for our own benefit. Conservation is
relevant to our time but should be viewed holistically. Conservation of our environment whether
natural or manmade is necessary because the beauty and creativity of a particular object can
never be recreated.
        Conservation aims to maintain the spirit of history in order to guide us to a better future.
Our environment is important to us entirely and not just in pasts. That is why area and landscape
conservation has gained such prominence today. Out efforts are to maintain the buildings in
good order and preserve them for future.
        One of the fascinating aspects of conservation of historical buildings is that it has endless
elements of challenge.      There is no field in engineering which has to be compared to
maintenance and conservation where fewer answers to vast problems are available. Conservation
of heritage structures is now emerging awareness in the community particularly due to human
urge to save and retain the structures which belongs to our past, to our fore fathers creation.
Conservation in the context of old structures has three subgroups of activities:
Preservation – which is maintaining the equilibrium with or without intervention, with normal
repairs and routine maintenance as required periodically. Conservation is highly skilled and
time-consuming operation before launching an ideal intervention technique and procedure.
Restoration – which means major structural intervention for repairs to foundations, column
masonry, roof and in some cases total rebuilding may be clone to some elements in parts or areas
of structures.
Rehabilitation – refers to the aspect of reuse of some building materials may be some new one to
match with original or an appropriate alternative use. It is in fact, modernization with or without
adaptive alternation.


2.1 Conservation In India
The concept of conservation and its relevance to India is a much-debated issue. With only a
handful of protagonists working to promote its cause, the majority of common people and
professionals remain unaware of the basic approach to watch conservation, alternatives available
and their applicability in a specific situation. For most people conservation is still associated



                                                  3
with archeological protection of historical monument or the romantic passion of a few
individuals observed with part.
       Doubts are expressed and questions are raised about the justification in spending time,
money and energy on buildings, which have outlived their original function. Judging by the
yardstick of economic feasibility and market forces many of the exiting structures could be
considered a liability. Simultaneously, however paradoxical, the idea of heritage is gaining wide
acclamation with heritage having become keyword of promotion of culture tourism and even
fashion. Many societies like Indian National Trust for Art and Culture Heritage (INTACH)
foundation for conservation and Research of urban Traditional Architecture (CRUTA) are
working for this cause.
Tourism came to India to window on its past no so much to exasperate on its present. And in
India, the present is not present enough.        It instantly stands wanting in comparison to
contemporary facilities and infrastructure elsewhere. So why not restore ruins and receive all of
developed nations to check in to the history in awe! There are hundreds of unsaved structures in
India. According to a survey it was found that there were more than 300 unsaved structures in
Amber near Jaipur.


3.0 CONSERVATION OF STRUCTURES
       General problems about the safety of the structures could be found in most of the old
buildings. However the fact that the buildings have survived for several decades should be
merited. Small distress could be stabilized by appropriate restraints but certainly it is no option
to rebuild a new. Decision making in conservation is most difficult task particularly for such
type of observations in old buildings.
       Most of the engineers are not familiar with the construction technique of traditional
structures and in fact, the avenues of load transfer mechanisms and options available in such
structures so as to make them efficiently perform so long. The calculations would reveal
permissible stresses are much higher than those limited by codal provisions. It is important to
remember that old buildings cannot be expected to conform the same standards that of new
buildings. If the buildings has survive without substantial damage or distress observations, why
calculations be produced to prove the contrary? This argument is purposely developed to
accumulate enough insight.


                                                4
       The problem of conservation generally deals with traditional buildings whose deep
understanding is required so as to know the manner in which such structures behave. These
decisions need not be necessary numerical analysis dependent.
       The buildings makes use of load parts which the engineer do not suspect and
consequently doesnot use in his analysis as many part of the buildings are load bearing and
engineer would not include those alternative parts in his calculations. There will be indefinable
fixities and unknown stabilizing factors and forces. Such factors combined together makes the
old buildings stronger than the calculations can establish.


3.1 Structural Monitoring
       It is feasible to install a simple but accurate method of monitoring the buildings for
structural movements or otherwise. There are simple and straightforward ways of checking
cracks, covering broad ranges of crack widths and their implications. It is relatively easy to
check the series of levels around the buildings for signs of settlement and modern electronic
distance measuring theodolite would permit the accurate checking of distances and angles in an
easy operations. Monitoring should however not be used as an excuse for putting of the
inevitable repairs but it will provides a very powerful ammunition when defending a decision not
to undertake expensive and disruptive strengthening measure.        It is important tot monitor
building carefully. Monitoring techniques need not be sophisticated but they have to be accurate.
It is often advisable to invest in a genuine basic monitoring to avoid spending huge sums of
money on remodeling measures, which may not be necessary. Proper structural monitoring is
always invaluable.


3.2 Factors Causing Deterioration Of Structural Elements
   Building elements deteriorate in a number of ways. It can be due to
      Structural movements of elements
      Weathering of elements
      Physical abrasion
      Disruption
      Erosion of stone
      Attrition by pedestrians


                                                 5
      Vehicular traffic erosion
      Acidic rain




Figure 1



3.3 Preparatory Works Befor Conservation
       The detailed survey of structure will depend no only on major construction elements but
would involve detailed scrutiny of stones and their joints inorder to gain an overall correct
impression of state of health of structures. Survey methods would vary according to time and
resources.
       Initial survey would be with binoculars and sketch books etc. This is further improvised
with sophisticated methodologies such as photogrammetry to compliment detailed inspections.
Use of scaffold of appropriate provisions are essential. Some of the sophisticated techniques
involve glass tell-tales, „demac‟, ‟gauges‟, LVDT‟s, laser beam theodolite, plumb bob, flat jack
pressure gauges and strain gauges etc. in addition, there are several proprietory devices for
measuring salt concentration, humidity, heat loss and so on.


                                                6
       The repair programme should be designed to arrest major structural damage and
movements as the first priority and then to deal with dentistry and cosmetic as subsequent phase.
       Typical schedule of work is as follows
Document and record the building fabric in its existing dilapidated state before work commence
and continue to update documentation at all the stages through out its repair.
Remove all vegetation by killing off with herbicides.
Decide an appropriate cleaning methodology, which would permit to protect friable or sensitive
elements susceptible to erosion during cleaning.
       Repair and arrest major structural movements by underpinning, constrain, buttressing and
consolidating, grouting and stitching etc.
       Prevent or attempt to arrest rising dampness where excessive salts are present.
Preserve, consolidate, repair, patch or replace sculptures and statues and decorative motives,
which are in danger of damage prior to conservation.
1. Assess the rubble or ashlar masonry from aesthetic viewpoint and consolidate repair, patch,
   replace, dress-back or leave it alone as appropriate.
2. Repoint as necessary to match the existing original mortar.


3.4 Washing Techniques
       Building facades need regular washing, which is seldom done. Normally rainwater wash
is not adequate, as it does not serve the desire purpose due to its repeated lashing over unwanted
areas along particular directions only. Cleaning projects the original aesthetic concepts.
       First and foremost, cleaning is a way of detecting little false before they become big
once. These act in two ways.
 i. The act of cleaning the building reveals faults like damage joints, brick work, cracks and so
     on.
 ii. In carrying out cleaning work a good cleaner will have chance of having thorough and close
     scrutiny of entire exterior of building.
   Cleaning can prevent the damage cause due to accumulation of SO2 content on building
fabric which may else result in damage. Also decay of soluble salts can be reduced by regular




                                                   7
cleaning. If cleaning is not proposed then other alternatives is to regularly paint it, which is also
rarely done.
    In order to decide the selection of correct cleaning techniques several factors need to be
considered.
       The material
       Location
       Age
       General state of repair it has undergone
Some of the cleaning techniques used are
   Grit blasting
   Water washing
   Chemical washing
They are governed by appropriate mixing and application techniques.
        Grit blasting, wet or dry, tends to be the method favored for cleaning where there are
heavy deposits on surface. It is vitally important that the operators are well experienced and take
personal interest in the work, as careless blasting is known to create irremedial damage to
features of carved stonework. Present day computer usage in buildings may not permit grit
blasting, as very little dust would jam up the whole work.
        Although grit blasting is appropriate for most of the buildings it may be desirable to clean
certain elements with chemicals.      At times, the stones are covered with appropriate paint
application and in order to explore the original glory of stonework paint has to be removed to
bring out the original fabric after washing. Suitable paint strippers are available under trade
names. It is not uncommon to find serious cracks in stonework and badly decay brickwork after
cleaning, which are otherwise completely concealed before washing.
        If the building is of limestone, it may very well receive and respond to water wash. In
case of water washing, extensive period of flooding are known to create brown stains, which are
difficult to remove.    The non-destructive cleaning is accomplished by water washing i.e.
continuous low-pressure water spray or in-situ chemical application. Both the methods require
high-pressure low volume water rinsing to flush away the soil loosened out by water spray or
chemical. Pressures of order of 1000 to 2500 psi at 4 to 8 gpm of water are used. Present water



                                                   8
washing techniques are generally effective and non-destructive for cleaning external surfaces and
are likely to have certain destructive effects on internal areas of the buildings. Continuous water
sprays usually attract their potential leak locations in the fabric of the buildings and these areas
cause considerable internal damage. However water washing is not labour extensive. The sprays
can be positioned to cover large surface areas with enough care required to monitor water
penetration and to control locations at windows with appropriate building blanking. If these two
problems of water penetration and iron staining are controlled this is a good low cost cleaning
method.


3.5 Technical Consolidation To Arrest Decay Of Stones
       Tried and tested techniques are preferable to new methods, which may have an
unforeseen detrimental effect on the building at some time in future.
Stone decay is to a great extent due to
 i. Erosion in cementing matrices in stone by acid attack.
 ii. Disruption of the stones intergranular bonds by increase tensile stress due to salt
     crystallization below the surfaces.
   Objective of consolidants is hence two fold. It should bind together the friable pore structure
and secondly it should prevent the migration of soluble salts without blocking the path of vapour.
       There are preservatives available, which respond in whole or in part. Some preservatives
have inherent fault, which are liable to break down and decay. For maximum efficiency vaccum
pressure impregnation is used but it is not practicable for very last structures that are not free
standing. Generally they are spread or brush apply as low viscosity liquids introduced by the
addition of solvents which offer good initial penetration but evaporate quickly bringing the
consolidant back nearer the stone surfaces. For the purpose of allowing the ingress of vapour,
pore lining consolidants are better than systems which fill the pores and block all traverse
leading to salt crystallization and internal stressing behind the impervious layers.
       Synthetic organic polymer system like, low molecular weight epoxide resins, nylons and
other ploy amide resins do substantially; improve the mechanical properties and durability of the
stone. However, the desired impregnation is difficult to achieve being totally impervious. They
can set enough problems in long run below the surfaces. In some forms these materials can also



                                                  9
cause embrittlement. Nylon too can absorb 2-3% moisture and swell with loss of strength and
will degrade on exposure to oxygen and ultra violet lights. Poly vinyl chloride (PVC), degrades
by photochemical process which releases damaging chlorine into the stone. Poly vinyl acetate
(PVA) in strong solutions are totally impervious and are therefore undesirable. They can also
produce gloss finish on the surface of stone.


Stone preservation using Silane
       This treatment involves impregnation of a stone to a considerable depth with resin based
alkoxy silane shortly silane. Treatment permits between 25mm to 50mm or so penetration. Such
deep penetration is useful for several reasons. It enables the preservation to consolidate friable
outer layer of the stone, it immobilizes the salts, which causes decay and it overcomes the
problem that causes the failure of the shallow coatings. Silane overcomes several restrictive
requirements of appropriate impregnation. It has very low viscosity. It is thin like water rather
than syrupy like engine oil.     Impregnation must also be able to cure at normal out door
temperature and it must not be hazardous in use. It is noted to be effective preservative and not
very expensive. The particular silane used as stone preservative are colourless moderately
volatile liquids with viscosities comparable to that of water. They react with water to give a
solid polymer. These are under detailed investigation for last over 20 years all over the world.


3.6 Dealing With Old Mortar
   Restoration of old mortar is yet another intriguing area. Several examples of good lime
mortar are observed in old constructions. The analysis of old mortars reveals variable lime and
sand contents according to the fineness modulus of the materials. The term mortar is infact used
for group of several materials and they are used for bedding, jointing and rendering of
brickwork, stone work etc.      The constituents of mortar are cementitious or other binding
materials with or without suitable filler or fine aggregates. Mortar must have certain properties
suggest developing early strength. It must bond well to the units. It must provide sufficient final
strength without forming cracks or other forms of deterioration. It must be durable. In making
the selection of mortar either for primary or restoration work, following parameter need be
considered.



                                                10
 Conditions of exposure
 Type of unit
 Possibility of chemical and bacterial joint attack
 Possible structural movement
Final properties of mortar should be considered carefully while making a choice of mortar for
specific jobs. The use of OPC and sand can yield very high strength mortars. Cement sand
mortars are routinely used as they eliminate the costly lime slaking process. However it is
important to realise that very strong mortar does not offer any allowance for unavoidable small
movements that occur in the buildings particularly masonry walls. These movements lead to
slight cracking of mortar and the brickwork. When lime mortars is used on its on, the material
available is weak enough to accommodate these small movements. However it is appropriate to
accept with modern construction work, that the line does not gain high enough early strength to
adhoc rapid construction to proceed.        Also some lime-based mortars are not suitable for
durability.
          The figure illustrates the way in which stone blocks are generally placed. This had led to
pressure built up, localised spalling as shown in figure 2. In extreme cases it may be necessary
to remove the entire block, but in many cases it would be possible to repair the joint as shown in
figure 3 and figure 4. The beds and joints should be raked out to a depth of 60mm or more, if the
soft mortar still exists. All the joints, should be well washed including water jet to prevent
mortar staining and to off load all the loose materials in the joints. The joints should be filled
with mixture of 1:3 cement and sand to a full depth opened out. The minimum possible quantity
of water should be used and the mixture properly trod with pointed tools, rods to give putty like
consistency of lime pointing to ensure proper keying back to within 3mm of surface. It is also
worth nosing down fresh pointing a day after it has been placed. This will allow the mortar to
take in some water. It helps to prevent rapid evaporation and development of the milky white
colour.
          It is necessary to analyse historic mortars for their lime contents which depends on it
purity and mortar proportions. Appropriate sample of all mortar about 20gms is collected from
old work. Suitable quantity of acid is added to find out measurement of evolved carbon dioxide



                                                  11
and with filtering and weighing of the acid insoluble components, the proportion of lime,
cement, sand can also be worked out.         Microscopic analysis of the mortar then suggest
appropriate source of quarry, river bed or beach sand comparing with known samples from area
around.


4.0 ADAPTIVE REUSE
       Structures that are built to endure the savageries of time are some time forced to change
their functions to reflect the constantly evolving cultural currents, the fluctuating real estate
values and developing progress in technology. Considering the scarcity of land, skilled labour
and funds it might be reasonable to expect that these historic buildings are viewed as a cultural
assets and adaptive reuse is suggested to meet the new demands and standards.


4.1 What Is Adaptive Reuse?
       Old buildings often outlive their original purposes. Adaptive reuse is a process that adapts
buildings for new uses while retaining their historic features. The idea behind adaptive reuse is
to maintain or restore the physical appearance of sound old structures while at same time
adapting them to full fill modern needs. Historic mansions and houses that for one reason or
another could not function as self-supporting museums have been converted to branch banks,
offices and student housing. Train stations, which are particularly expensive to maintain, have
gained new lives as restaurants, shops, schools, science museums and hotels.
       One famous example of adaptive reuse is the Gallery of Modern Art for the Tate museum
in London. The museum was once a power station. It was constructed in 1947. The power plant
shutdown in 1981 and this was transformed in 2001.


4.2 Adaptive Reuse In India
       The idea of adaptive reuse has been formally in vogue in India as a conservation strategy
for a relatively long time now. However it might be a much more powerful as a strategy, to look
for compatibility of meanings in the search for appropriate adaptive reuse. If one were to look
for the suitability for adaptive reuse by compatibility in meaning, one is likely to underscore the




                                                12
original urban pattern as well. A palace converted to a town hall retains the administrative and
civic center at the same locus, however a palace converted into hotel does not.




4.3 Economic Profile Feasibility Study
       In reality there is no purpose in considering a new use unless it will produce some
financial returns. Also the most appropriate long term use which generates the best financial
return; but should be the one which is most economically viable and consistent with the historic
form and character of the building. A genuine cost appraisal and feasibility study is required
before deciding the fate of the building.
       This feasibility study should demonstrate that sufficient return will be produced to ensure
that a building can be properly maintained and preserved in the long term. Thus a feasibility
study of the cost of works and potential returns from potential new users will be required as a
part of the initial project assessment. Viability studies as with all valuation and appraisal work
can never be treated as an exact science.    The purpose of study is to assess the parameter of
profit or loss of a project according to assumptions made on cost and income.
       This will require an initial inspection to note structural problems, advice on the most
suitable form of use, categorization of defects and restoration techniques determining optional
uses in this context and estimating the consequent and value in light of local market conditions
during the period of conservation works.


4.4 Adaptive Reuse Conversions Of Non-Residential Buildings To Residential
Housing-case study
Ashdown Warehouse
Winnipeg


Introduction
       The Exchange district is a 30 block down town area in the historic heart of down town
Winnipeg, which flourishes as the city‟s commercial and cultural center. It contains most of the


                                                13
Winnipeg‟s heritage buildings and was later designated as a national historic sight. There is
much interest for the conversion of existing heritage buildings to mixed or residential use.
       The Ashdown Warehouse conversion has been launched as the best example for a non-
residential to residential conversion for market housing in Winnipeg.


Building Features
       It was designed by S.F.Peters in 1895 with no subsequent additions until 1911. It is an
exceptional example of Richadson Romanesque, with a Selkirk stone foundation, Portage la
Prairie buff brick exterior and deeply modeled brick detailing, with notable façade elements such
as arch windows on the third floor. The owners of the property had previously operated a
manufacturing business in the building.


Clients Brief
       An initial attempt to complete this project with a large developer was unsuccessful. The
buildings prominence, historic significance and location were key in gaining the support of the
government, which was essential to a success of a project.           The owners as well as the
government wanted the building to demonstrate the adaptive reuse of existing buildings in the
heritage district could be lucrative.


Description
       While the historic designations pertained principally to the exterior, the owner understood
that the interior also provided a significant market advantage. Considerable efforts and cost were
spent to maintain the interior appearance of heavy timber framing and exposed brick. The
exterior brickwork was restored to its original appearance, power wash and repainted where
necessary. New high performance double hung aluminium windows and frames were installed
to match the original wooden windows. Interior brick walls, wood columns, beams and purlins
were sand blasted and left exposed. Some of the old equipment from the buildings previous
industrial uses are displayed in public areas of the buildings.




                                                 14
         A wheel chair ramp was installed at the back of buildings exterior in place of the
mechanical lift placed initially. The underground garage is accessible. The suites were built with
backer board.
         It was established early in the process that the upper flows would be a condominium
development, while the ground floor would cater to commercial retails use. The floor to floor
heights varied from 12‟ to 13‟6”. The plan incorporated five interior skylit atria extending
through five floors. Natural light is brought to the center of the building and day light provided
to adjacent studios and bedrooms. While removing floor area this design decision increased
viability and marketability.
         The building was structurally compatible with the loading imposed by its new uses. The
original construction had occurred in six phases and building was subdivided in five
compartments of four masonry – bearing walls. An early structural analysis establish parameter
for the location and size of openings through these walls, enabling design work to proceed to a
buildable concept. The existing structure was open and exposed, which let to few hidden
problems.
         The concrete topping was placed on fireboard to cushion impact generated sound and batt
insulation added between dry wall ceiling and the wood flooring. Carpet was recommended to
further cushion sounds, but some tenants apply hardwood or ceramic tile to the concrete allowing
impact noises to be audible below.


Result
         The project achieved it heritage and cost objectives and was well received by the public,
however, sales was slow due to the recession of early 1990‟s. The ground floor commercial
space has not been as successful as first hoped.


5.0 CONCLUSION
         When looking at heritage buildings it becomes imperative to analyse it with a pragmatic
approach. A blanket conclusion, that all heritage buildings should be preserved for posterity
would stagnate the building itself. In any era, more than 20-30% of old buildings cannot be




                                                   15
preserved. If a project is found to be capable of adapting itself to a new use for its continuity than
all incentives should be provided to make it an economically feasible proposal.


ACKNOWLEDGEMENT
       I express my sincere thanks to Dr A.K.Raji for her help in guiding me to complete this
seminar. I would also like to thank Dr. K.B.Anand for his timely help in completing this
seminar.I would also like to thank my friends for their moral support and encouragement during
the course of the seminar.


REFERENCES
1. Aman Nath, “Erstwhile Worthwhile?”, INDIAN ARCHITECT & BUILDER,Vol12,August
   1999, pp80-81
2. Alpha Seth, “Interview with Architect Lim”, INDIAN ARCHITECT & BUILDER, Vol17,
   December 1993, pp 66-70
3. Kailash Khemlani, “A Rational Alternative”, INDIAN ARCHITECT & BUILDER, April
   1999, pp 76-81
4. Raikar,R.N., “Heritage Conservation of Structures – Some Guidelines”, Durable
   structures through planning for preventive maintenance, pp 119-131
5. http:/www.cmhc-schl.gc.ca




                                                 16

								
To top