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nt. J. Environment and Sustainable Development, Vol. 14, No. 1, 2015 1
Copyright © 2015 Inderscience Enterprises Ltd.
A decision support tool for the adaptive reuse or
demolition and reconstruction of existing buildings
Eleni Sfakianaki*
School of Social Sciences,
Hellenic Open University,
57-59 Bouboulinas Street,
52622, Patra, Greece
Email: esfakianaki@eap.gr
*Corresponding author
Katerina Moutsatsou
School of Social Sciences,
Hellenic Open University,
57-59 Bouboulinas Street,
52622, Patra, Greece
Email: kmoutsatsou@teemail.gr
Abstract: A large number of old and abandoned buildings are under restoration
with a view to accommodate new functions, while some others have already
been consolidated and reconstructed. The decision whether to interfere and to
what extent to an existing building is a complex issue which should take into
consideration the broad range of all sustainability concerns. This means that the
decision should examine not only a number of environmental factors but also
social and economic indicators as well as maintenance in terms of cost, time,
quality and performance within an acceptable range. This paper explores the
relationships between financial, environmental and social parameters associated
with building adaptive reuse or demolition and reconstruction. A weighted
decision support tool (WDST) has been developed and discussed in this
context. This tool can assist in the transformation of the traditional empirical
decision-making processes of building stakeholders, towards more sustainable,
profitable and cultural respectful practices.
Keywords: adaptive reuse; demolition; decision support tool; eco-costs;
building value.
Reference to this paper should be made as follows: Sfakianaki, E. and
Moutsatsou, K. (2015) ‘A decision support tool for the adaptive reuse or
demolition and reconstruction of existing buildings’, Int. J. Environment and
Sustainable Development, Vol. 14, No. 1, pp.1–19.
Biographical notes: Eleni Sfakianaki is an Assistant Professor in the School of
Social Sciences at the Hellenic Open University. She graduated as a Civil
Engineer from the Civil Engineering Department of the University of Patras
and she then undertook an MSc course in Construction Management at the
University of Sheffield in the UK. The University of Sheffield awarded her a
full scholarship to undertake a PhD, the subject of which was on environmental
impact assessment with the use of geographical information systems. Her areas
of expertise include environmental impact assessment, environmental
2 E. Sfakianaki and K. Moutsatsou
management, sustainability, life cycle assessment, decision analysis, teaching
and learning in higher education. She has also worked as a consultant in the
project and environmental management of large scale projects.
Katerina Moutsatsou is a graduate of the Architectural School of the National
Technical University of Athens. She has undertaken an MSc course in
Management in Construction at Kingston University and she is currently a PhD
student at the Hellenic Open University. Her research concentrates in the fields
of sustainable buildings, decision-making and environmental impacts. She is a
registered engineer and has many years of work practice.
1 Building stock in Europe and Greece
Sustainability is a concept that has been widely spread when the Bruntland Report ‘Our
Common Future’ was published in 1987. Since then, it has been generally acknowledged
that sustainable development has three pillars: environment, society and economics. The
role of construction is important in the international economy, with considerable impact
on the environment. Buildings use resources in many different ways such as through the
manufacturing process in which the building components are produced, through
transportation of materials to the construction site and through operation when the
building is occupied (Retzlaff, 2009). Naturally, resources are also employed when a
building is demolished in which case recycling or disposing of materials is required
(UNEP, 2007). It is therefore only rational to link the construction sector with the concept
of sustainability, considering the environmental impacts arising from the energy
consumption during the use and the processing of the natural resources during all stages
of the building life cycle.
The building industry started to recognise the impact of their activities on the
environment in the 1990s. A shift in thinking was required to reduce the impact of
construction on the environment. It was essential to rethink how the buildings were
initially designed and subsequently built and operated. In order to improve the
sustainability of a building, all the sustainable dimensions right at the early design phases
of the building project need to be considered. In this respect, it is important to consider
the entire life cycle of a building when evaluating its sustainability and in some cases, it
may be environmentally better to re-use buildings instead of constructing new ones. Most
developed countries have a substantial stock of existing buildings in many different states
of repair and utility. Unfortunately, it is quite common, when the useful life of buildings
expires, to remain abandoned without any use. Usually the older the stock is, the poorest
the physical condition. The maintenance therefore and refurbishment of existing
buildings are critical issues for sustainable building construction as Kohler and Moffatt
(2003) argue.
It is indicative that in the EU-25, the number of dwellings is about 196 million. Half
of the existing residential buildings were built before 1970 and about 1/3 of the dwellings
were built during the 1970 to 1990 (Norris and Shiels, 2004). The annual rate of
construction of new dwellings represented as a percentage of the size of existing stock
ranges from 0.3% in Sweden to 3.5% in Ireland and 3.9% in Greece, with an average of
1.1%, while the estimated annual replacement rate (ratio of the annual demolition rate to
the size of existing stock) for dwellings in Europe is only 0.07% (Hartless, 2003). About
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decision support tool for the adaptive reuse 3
70% of the residential buildings are over 30 years old and about 35% are more than
50 years old. This is an important observation showing that most of buildings in Europe
have been constructed based on obsolete national building regulations for construction,
energy consumption and installations for disabled persons. It is expected that the
emphasis in Western Europe will shift even more towards renovation and maintenance of
existing housing stock, instead of new constructions, with the economic recession.
Sleight (2005) had already forecasted that growth in European construction will slow
down, with new housing construction expected to be 0.7% in 2011 compared to 4.4% in
2004.
In the case of Greece, there is a large number of abandoned buildings as indicated by
the Hellenic Statistical Authority in 2000. Indeed, the observations are that in 1991,
31.91% of the existing buildings in Greece were abandoned, while 10 years later, the
percentage had increased to 33.29%. It is remarkable that this result once translated into
real numbers, it refers to approximately 2,500,000 abandoned building cells without any
use. Clearly, this is a considerable amount of the built environment in Greece and it
affects not only cities but regions also.
It can be argued that one reason for such result is urbanism; however, it is only a 20%
to 25% of abandoned buildings that lies in small towns of North and South Greece.
Remarkably enough and beyond the concept of urbanism, 38.5% of abandoned dwellings
are in the centre and suburbs of Athens, capital of Greece, which retains the problem of
the large number of abandoned buildings. Table 1 illustrates the number of buildings in
different time periods and their age in national level. It is also noticeable that a significant
number of dwellings in Greece were constructed between 1960 and 1980, when Greece
faced a great boost in construction sector. Since then, a decrease in the number of
building constructed is observed.
Table 1 Existing buildings in different time periods and their age
Years Number Age
Before 1919 199,510 > 92
1919–1945 406,633 91–66
1946–1960 665,315 65–51
1961–1970 761,182 50–41
1971–1980 737,575 40–31
1981–1985 404,303 30–26
1986–1990 297,348 25–21
1991–1995 241,615 20–16
After 1996 191,739 < 16
Under construction 57,430 < 16
Not subscribed 28,320 -
Total number of buildings 7,896,190 -
Source: National Statistical Service of Greece – Inventory (2002)
Irrespective of a country having a large or small number of abandoned buildings, a
solution is necessary. The question is which type of intervention should be attempted to
old buildings which following the term of sustainability will be environmentally wise and
4 E. Sfakianaki and K. Moutsatsou
economical and socially accepted. Should we attempt to give new life to these buildings?
Or would it be better in an environmentally friendly way to demolish and start a new
building following all the new and modern regulations? The decision whether to interfere
and to what extent to an existing building could not be clearly a one way decision. There
are many alternative ways to interfere to an existing cell depending on the case and the
situation of the building. The pertinent options are described in the following section.
2 Re-use or demolish
There is no doubt that buildings are major assets and although it can be argued that they
last for long, they also require maintenance during their life cycle. Eventually, buildings
may become inappropriate for their original purpose due to obsolescence, or can become
redundant due to change of the demand for their service. In this case a change may be
required and the question posed often is to demolish to make a new construction or to
refurbish or adaptively reuse it (Langston et al., 2008). Either decision affects
environmental, financial and social parameters which should be taken into account before
finally deciding about the future of the building.
According to Thomsen and van der Flier (2008), the construction of new residences is
declining below 1% of the existing stock annually to date. Consequently, the ageing stock
is growing and as such the knowledge about old buildings, although new construction is
still the dominant approach for developers. The authors however argue that knowledge on
demolitions is very limited since the volume of demolitions is very low. For example, in
the Netherlands less than 0.2% of the existing residential stock is demolished and in most
other EU countries the percentage is even lower. As it is argued, besides the
technological aspects of demolitions, the decision to demolish is first of all a managerial
decision dependent largely on the owner.
Demolition is an intervention with potentially severe social effects, on individuals as
well as on society. Demolition implies, in practical terms, loss of living and working
space and in economic terms, destruction of capital. In environmental terms, the
demolition waste together with the use of the new building materials is undisputed a
substantial environmental load. More specifically, the environmental impacts from this
phase arise, amongst others, from the manufacturing of materials and the energy
consumption during this process, the energy required for the disposal of demolished parts
and materials, not to mention the transportation and construction needs while recycling. It
is believed that demolition plus replacement is most likely less sustainable than life cycle
extension of the existing building (Thomsen and van der Flier, 2008). In the European
housing market where the stock is ageing, there is growing debate about the future of this
stock and whether demolition followed by new construction or life cycle extension is the
solution.
Langston et al. (2008) further argue that existing buildings that are obsolete or
towards the disuse stage and potential demolition are a very good source of raw materials
for new projects. However, they also argue that it is more effective instead of extracting
these materials during demolition and either using them to new projects, or even trying to
find means for recycling them, to leave the basic structure of the building intact and
change its use. This is what is called according to Langston et al. (2008) ‘adaptive reuse’
and besides the new life that breathes into the existing building, it also brings benefits in
environmental and social terms and at the same time helps to retain national heritage.
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decision support tool for the adaptive reuse 5
Bullen (2007) in a slightly different interpretation states that adaptive reuse is
“rehabilitation, renovation or restoration works that do not necessarily involve a change
of use”, and supports that adaptive reuse ‘extends the useful life and sustainability in a
combination of improvement and conversion’. Douglas (2006) however felt that adaptive
reuse involves conversion to change of use required by new and existing owners’ and this
is a view held by others (see for example, Davidson and Dolnick, 2004). Despite the
different readings of the same term, the bottom line that is adequate for the present
research is that the term of adaptive re-use refers to a building that is not demolished; on
the contrary it is re-used following the necessary works irrespective of keeping the same
use or changing it.
According to Roders (2006), there are seven scales of intervention on an existing
building cell starting with the lower scale – deprivation (scale one), preservation (scale
two), conservation (scale three) and restoration (scale four); to superior scale –
reconstruction (scale six) and demolition (scale seven). Feilden (1982) sustained that the
best way to preserve a building is to keep it in use and emphasised that the adaptive
re-use of buildings is perhaps the only way to save in an economic manner historic and
aesthetical values and at the same time bring up to contemporary standards historic
buildings. Adaptive reuse although is a challenge in many respects, for example design
and permitting, it offers economic, environmental and social benefits making it an
attractive solution to developers.
Considering that the present research poses the question to demolish or re-use a
building, an important tool in the present analysis is the life cycle of a building. The life
cycle of a building, ‘from cradle to grave’, refers to the view of a building during its
entire life and is divided into phases to enable comparisons of the buildings’
performances. The traditional approach presents the different phases of the building’s life
cycle with a linear relation. The sequential life cycle (SLC) of a physical construction can
be divided in different activities such as materials extraction, manufacture of
components, transportation, construction, use, refurbishment, use and adaptive reuse of
the existing physical construction. In SLC, the refurbishment stage refers to operation and
maintenance as a continuous process while after the adaptive reuse of the building the life
cycle starts from scratch.
Before however a decision is reached, it is important to discuss how the building’s
performance is usually evaluated. Many tools have been developed attempting to provide
an objective evaluation measuring amongst others, resource use, ecological loadings and
energy consumption. A description of these tools follows on the following section.
3 Building assessment systems
Cole (1998) argues that it is difficult to precisely define what ‘building performance’ is,
since there are several different parties with different interests and requirements in the
building sector. For example, renters and lodgers are interested in luxury and comfort
whereas developers focus more on equity and financial performance in general, (Haapio
and Viitaniemi, 2008). In order to address the needs of the different groups of interest, a
common set of criteria were developed the scope of which was to assess the
environmental impact of buildings, to collect information on the building and its
operation, to assist in the design of buildings in a sustainable way, and to monitor the
6 E. Sfakianaki and K. Moutsatsou
impacts of construction on the environment (Cole, 1998). In this way, the concept of the
building assessment system was developed which is a tool that rates how well a building
is performing or is expected to perform according to the specified set of criteria (Cole,
2005).
According to Retzlaff (2009), building assessment systems were adopted initially in
the US on a voluntarily basis. The first approach widely known that addressed a large
range of issues in a single tool was the Building Research Establishment Environmental
Assessment Method (BREEAM) in 1990 in the UK (Crawley and Aho, 1999). Since
then, a large number of methods has been developed such as ATHENA Environmental
Impact Estimator, Building Environmental Assessment Tool (BEAT) 2002, BeCost,
Building for Environment and Economic Sustainability (BEES) 4.0, BREEAM,
EcoEffect, Envest 2, and Leadership in Energy and Design (LEED), (for a broad
discussion see for example, Larsson and Cole, 2001, DOE, 1996/2006; IEA Annex 31,
2001; Reijnders and Roekel, 1999).
As Wallhagen and Glaumann (2011) explain, the majority of the assessment tools
assembles a large number of environmental issues, then weights and aggregates the
various aspects into overall judgements. Cole (2005) argues that environmental
assessment tools can broadly be divided into two categories, those that are based on
life cycle assessment (LCA) principles and those that are not. Most LCA-based
environmental assessment tools such as the Athena Environmental Impact Estimator and
Envest are used as the basis of evaluating materials or other strategic design options.
Other types of methodologies applied in assessment techniques relate to scoring
performance (e.g., aggregation of points; eco-efficiency-based) and to the derivation of
weightings (e.g., expert consensus, analytic hierarchy process, etc.) (Cole, 2005).
Although the methods developed vary to a great extent, they aim to assist some common
purposes: to motivate owners and developers to improve the performance of their
buildings, to notify all pertinent parties on the level of impact of buildings in
consideration, and to measure in an objective manner the impact of buildings in question
(Brochner et al., 1999; Cole, 1999). Some of these methods such as ATHENA and BEES
also provide the option of costing which will be further examined below.
More integrated approaches have also been developed in the past which further
illustrate the importance of assessment methods. For example, de Jonge (2005) based on
the theory of Vogtländer (2001a, 2001b) related sustainable investments such as building
costs and operational costs to eco-costs. The aim of the research was to develop a tool
which provides information on the environmental burden of housing projects, related to
the design characteristics with the scope to be used at various stages in the design and
development process, both new construction, redevelopment and renovation projects. The
tool ultimately provides the decision maker with assistance whether to renovate or to
redevelop. In the same context, Itard et al. (2006) examined the challenge of large-scale
urban restructuring and urban renewal of post-war neighbourhoods. The research adopted
an LCA-based tool (EcoQuantum) and in order to take into consideration the dynamic,
and not static, behaviour of buildings adapted calculations to the dynamic aspects of a
building for the aspects of energy use. De Jonge (2006) explains that the possibilities of
improving the energy performance of existing housing are limited. This raises the
question how to balance energy use of old buildings against that effects of emissions and
materials depletions of new construction.
Although there are many tools to assess existing buildings, new buildings, etc., the
focus of the present study is on existing buildings and the research hypothesis is whether
A
decision support tool for the adaptive reuse 7
it is worth maintaining an old building or demolishing it. In the prism of sustainable
buildings, a number of requirements are set for the assessment tools in addition to the
environmental aspect, which concern the economical and the social aspects that need to
be considered and included in the assessments. In addition to the fact that despite the
large number of building assessment systems, there has not yet emerged a single system
that is widely accepted; all these set the benchmarks for the development of a new
decision-making tool for the evaluation of existing buildings.
4 The decision support tool
The concept of sustainability concerns not only environmental but also economic and
social factors. As Bragança et al. (2010) explains, a building in order to be sustainable, it
must obey a number of factors besides the respect for the environment which are social
integration and social economy, maintenance in terms of cost, time, quality and
performance within an acceptable range. This is further verified by a number of studies
(such as Power, 2008) which investigate the feasibility of an intervention to an existing
building cell. Most of the studies indicate that, the factors arising from the dilemma
whether to adopt and reuse a building or demolish and reconstruct, can be divided into
three main categories: environmental-ecological factors, economical-financial factors and
Sentimental-social factors. In this respect, the present research develops a decision
support tool for the assessment of potential adaptive reuse of buildings and discusses how
this potential can be validated based on a triple bottom line (financial, environmental, and
social) philosophy.
4.1 Environmental – ecological factor
In the case of the building’s environmental evaluation, a significant number of models
that assess its performance have been developed as illustrated in Section 3. The present
research has adopted for the environmental factor the basic principles of the eco-costs
and the eco-costs value ratio (EVR) model developed by Delft University of Technology
(Vogtländer, 2001a), which expresses ecological burden in economic terms. The
theoretical framework of the eco-costs model is described in Figure 1. Eco-costs are
based on the concept of ‘marginal prevention cost’, or else the costs that are required to
bring back the environmental burden to a sustainable level. Eco-costs are a single life
cycle analysis-based indicator for environmental burden and are a measure to express the
amount of environmental burden of a product or a building on the basis of prevention of
that burden. Vogtländer (2001b) tried to handle the following dilemma; the growing
economy seems to be one of the major reasons for the deterioration of the environment
however stopping the growth seems unrealistic. He therefore developed his theory on the
concept of better eco-efficiency of systems for production and consumption.
More analytically, the EVR model links the ‘value chain’ to the ecological ‘product
chain’. In the value chain, the added value in terms of money and the added costs are
defined for each step of the product (from cradle to grave). In the same respect, the
ecological impacts of each step in the product chain are expressed in monetary terms
which are called eco-costs. It should be mentioned that eco-costs are not real costs but
virtual.
8 E. Sfakianaki and K. Moutsatsou
Figure 1 The eco-cost chain combined by the ecological product chain
Source: Vogtländer (2001b)
The outcome of the implementation of this theory, for each process, product or service is
the ratio of the value and the eco-costs. This eco-costs/value ratio can be defined at any
aggregation level of the chain based on equation (1):
Eco Costs
EVR Value
−
= (1)
where a low EVR indicates that the product is appropriate for use in the sustainable
society. Conversely, high EVR indicates that the value/costs ratio of a product might
become ‘less than one’ in the future, since ‘external’ costs will become part of the
‘internal’ cost-structure. In this respect, the EVR serves as an indicator for sustainability
in LCA in case where the quality of products differs. In the decision making process of
an intervention to an existing building, the quality of the initial product is the same. For
this purpose, the value factor is omitted, while the actual target of this phase is to predict
just the environmental burden of the decision or otherwise the energy consumption of the
intervention expressed in financial terms.
The calculation model includes ‘direct’ as well as ‘indirect’ eco-costs. The first
category includes costs such as costs required to reduce the emissions in the product
chain to a sustainable level, eco-costs of energy which is the price for sustainable energy
sources and eco-costs of materials depletion. In the latter case, costs are the eco-costs of
depreciation such as the eco-costs related to the use of equipment, buildings, etc.,
eco-costs of labour are the eco-costs related to commuting and the use of the office
(building, heating, lighting, electricity, etc.). All the elements calculated in the eco-cost
model, are calculated according to the LCA method as defined in ISO 14041. The
eco-cost model is applied in the context of the life cycle of a building presented in
Section 3. For each stage of the buildings life cycle (L), reference is made to the different
kinds of embodied and cumulative energy of the building.
The advantages of the proposed model besides it being available for use at no cost, is
that it provides a platform for comparisons since results are interpreted in monetary terms
enabling the actual costs of construction (demolition or re-use) to be embed in a unified
system. It is a method to express the amount of environmental burden of a product or a
building on the basis of prevention of that burden. The advantage of this method is the
flexibility of the calculations. Even if it is not based on a special software and belongs to
the basic calculation method of LCA, conducted in an excel spreadsheet, the outcome of
the method gives advanced results for the environmental impact of a product or service
easily explainable to non-experts and transparent for specialists. Once the eco-cost
method is applied aiming to calculate building energy, the export data in Euro even if the
import data is energy units measured in KJ/Kg. Consequently, the analysis of the energy
concludes in equation (2):
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decision support tool for the adaptive reuse 9
-cos -cos ( ) - cos (int )
()
ii
Eco t Eco ts initial Eco ts ervention
TotalEnvironmentalIndicator TEI
=+
= (2)
where i = 1, 2, 3, …, 7 (types of intervention based on Table 2).
Table 2 Type and scale of intervention
Scale of intervention i Type of intervention
Scale one 1 Deprivation
Scale two 2 Preservation
Scale three 3 Conservation
Scale four 4 Restoration
Scale five 5 Rehabilitation
Scale six 6 Reconstruction
Scale seven 7 Demolition
Source: Roders (2006)
4.2 Financial factor
Besides the actual calculations for the assessment of the environmental impact of a
building intervention (demolish or re-use) interpreted in terms of energy consumption,
the actual costs associated with its potential investment (demolish or re-use) during the
building’s life cycle should not be overlooked. The purpose of this analysis is the
prediction of the total cost for the stakeholder in each type of intervention to the existing
building. Life cycle costing (LCC) analysis is used by the present research as an analysis
over the whole life cycle of a building. There is a large number of economic evaluation
methods for LCC analysis, the most commonly used are presented in Table 3 together
with their advantages and disadvantages.
According to Schade (2007), the most suitable approach for LCC in the construction
industry is the net present value (NPV) method. NPV is the result of the application of
discount factors, based on a required rate of return to each year’s projected cash flow,
both in and out, so that the cash flows are discounted to present value (PV). According to
Kishk et al. (2003), the NPV is what is needed in terms of cost to be invested at present,
to meet future financial requirements throughout the life of the project and in this respect
the lesser the NPV of an alternative the better. The important contribution of the NPV
method is that it takes into account the time value of money.
10 E. Sfakianaki and K. Moutsatsou
Table 3 Economic evaluation methods for LCC
Method What does it calculate Advantage Disadvantage Usable for
Simple payback Calculate the time required to return the initial investment.
The investment with the shortest pay-back time is the most
profitable one.
Quick and easy
calculation. Result
easy to interpret.
Does not take inflation, interest or
cash flow into account.
Rough estimation if the
investment is profitable.
Discount payback
method (DPP)
Basically the same as the simple payback method, it just
takes the time value into account.
Takes the time value
of money into account.
Ignores all cash flow outside the
payback period.
Should be only used as
a screening devise not
as a decision advice.
Net present value
(NPV)
NPV is the result of the application of discount factors, based
on a required rate of return to each year’s projected cash
flow, both in and out, so that the cash flows are discounted to
present value. In general if the NPV is positive it is worth
while investing. But as in LCC the focuses is one cost rather
than on income the usual practice is to treat cost as positive
and income as negative. Consequently the best choice
between two competing alternatives is the one with minimum
NPV.
Takes the time value
of money into account.
Generates the return
equal to the market
rate of interest. It use
all available data.
Not usable when the comparing
alternatives have different life
length. not easy to interpret.
Most LCC models
utilise the NPV method
Not usable if the
alternatives have
different life length.
Equivalent
annual cost
This method express the onetime NPV of an alternative as a
uniform equivalent annual cost, for that it take the factor
present worth of annuity into account.
Different alternatives
with different life’s
length can be
compared.
Just gives an average number. It
does not indicate the actual coast
during each year of the LCC.
Comparing different
alternatives with
different life’s length.
Internal rate of
return (IRR)
The IRR is a discounted cash flow criterion which determines
an average rate of return by reference to the condition that the
values be reduced to zero at the initial point of time. It is
possible to calculate the test discount rate that will generate
an NPV of zero. The alternative with the highest IRR is the
best alternative.
Results get presented
in percent which gives
an obvious
interpretation.
Calculations need a trial and error
procedure. IRR can be just
calculated if the investments will
generate an income.
Can be only use if the
investments will
generate an income
which is not always the
case in the construction
industry.
Net saving (NS) The NS is calculated as the difference between the present
worth of the income generated by an investment and the
amounted invested. The alternative with the highest net
saving is the best.
Easily understood
investment appraisal
technique.
NS can be only use if the investment
generates an income.
Can be used to compare
investment.
Source: Smullen and Hand
(
2005
)
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decision support tool for the adaptive reuse 11
However, this method compares alternative ways of intervention but with the restriction
of the same life length of building for both alternatives. This renders the existence of a
predefined period of study mandatory. In this respect, this method cannot be used when
the alternatives being compared have different life lengths since in this case the
interpretation is very difficult with disputed outcomes. This obstacle is overcome when,
for the basis of comparison, there is a pre-defined limited time period. As such, using the
NPV method, all costs by year are initially identified and quantified and subsequently are
discounted to PV. They are finally added to calculate the sum of life cycle cost for each
of the possible alternative type of intervention. Based on the above and according to
Sieglinde (2010), the LCC of the building under consideration based on NPV and
pertinent the analysis concludes to equation (3):
-Re & ( )
iiiiii
LCC I Repl s E W OM R O TotalCostIndicator TCI=+ + + + + = (3)
where:
I PV of investment costs
Repl PV of capital replacement costs
Res PV residual value (resale value, salvage value) less disposal costs
E PV of energy costs
W PV of water costs
OM&R PV of non-fuel operating, maintenance and repair costs
O PV of other costs
i 1, 2, 3, …, 7 (type of intervention based on Table 2).
The present research for the purposes of comparison has predefined the period of study to
50 year as a good perspective for the useful life of construction projects. For both
alternatives (demolish or re-use), it is assumed that the initial costs (Ι), such as capital
investment costs for land acquisition, construction and necessary equipment for the
operation of the facility, are equal. Furthermore, for the basis of comparison, it is also
assumed that the capital replacements (Repl) of a building system remains the same since
the number and the timing of capital replacements of building systems depend on the
estimated life of the system and the length of the study period. The residual value of a
system (Res), components or materials is its remaining value at the end of the study
period, or at the time it is replaced during the study period. Residual values can be based
on value in place, resale value, salvage value, or scrap value, net of any selling,
conversion, or disposal costs. Components or materials in the case of demolition
considered to reach the initial cost, because of a total displacement or destroy of the
component or the system. In this case, the difference between the capital replacement
costs (Repl) and the residual value is equal to 0, (Repl – Res(i) = 0, where i = 7).
12 E. Sfakianaki and K. Moutsatsou
4.3 Sentimental – social factor
The last factor that is included in the proposed tool concerns the sentimental factor that
should be part of any sustainable approach. When building values are examined, the
decision to demolish or reuse an existing building has a sentimental dimension which in
the case of the present research is interpreted as the social factor. It is worth to compare a
building to a monument with a view to distinguish the different kinds of value
accumulated in its cell. This interpretation has been based on Riegl’s research (1982),
first published in 1930, which argues that the built up environment could be seen as a
collection of monuments from the existence of a community. The study distinguished
monuments to two kinds, intentional and unintentional. An intentional monument is “a
human creation, erected for the specific purpose of keeping single human needs or events
(or a combination thereof) alive in the minds of future generations” (Allen, 2009)
whereas unintentional monuments, which are much more numerous, are remains whose
meaning is determined not by their makers, but by the modern perceptions of these
monuments. An argument however to the latter is that in modern age all monuments
(buildings) could be seen as intentional to a certain extent, since they were built for a
specific purpose and their meaning is not yet determined by their makers, but by their
users or by our perception of these monuments.
Based on Riegl’s (1982) theory, different ages encourage the cult of different values
and our attitude towards conservation depends upon which values are attributed to the
monument. The distinction has been established not with a purpose to overlap one value
over another, but in an effort to identify the processes of valuation that determine
different approaches to conservation. More specifically, Riegl developed five different
kinds of values namely the memory value, age value, historical value, use value and art
value.
Quantifying building values is not a straight forward process. Conversely to the
previous two factors (environmental and financial), the sentimental factor, as a
non-tangible parameter, is much harder to measure and eventually conclude to a single
equation as in cases of equations (2) and (3) expressing outcomes in monetary terms. To
overcome this difficulty, a ranking table, based on Riegl’s theory (1982), is introduced
aiming to measure the sentimental factor as illustrated in Table 4. In this way,
stakeholders (x) have the opportunity to rank the five building values with a grade that
varies from [0.1–0.3] where grade 0.3 could be interpreted as the building value that is
not significant at all, while value with grade 0.1 is the most significant for the
stakeholder.
Table 4 Ranking table for the sentimental factor
Values Ranking range
Use value
0.1–0.3
Memory value
Historical value
Age value
Architectural value
A
decision support tool for the adaptive reuse 13
(
)
()
iii i
ii
R x UseValue MemoryValue HistoricalValue
AgeValue ArchitecturalValue
=++
++
∑
(4)
where i = 1, 2, 3, …, 7 (type of intervention based on Table 2), and x = a, b, c….
(different stakeholder).
The outcome of Table 4 defines the cumulative value of an existing building,
expressed with a ranking factor R(x)i which could vary from 0.5–1.5 based on the ranking
table where the lowest grade is 0.1 and the greatest 0.3. In the cases of demolition and
reconstruction, the values of this category are omitted. The final calculation of the value
indicator is based on the average of the results of equations (2) and (3) multiplied with
the ranking factor R(x)i as illustrated in equation (5). In this respect, we produce a more
comparable and less sensitive basis for comparisons.
(
)
-cos () ( )
2
ii
ii
Eco t LCC
Value R x TotalValueIndicator TVI
+
=×= (5)
where i = 1, 2, 3, …, 7 (type of intervention based on Table 2).
It is important to emphasise that the outcomes of all equations (2), (3) and (5) are
expressed in monetary terms (Euros) providing a common basis for comparisons.
4.4 The weighted decision support tool
The scope of the present research is twofold; to identify and establish the triple bottom
line of the environmental, economic and social indicators that affect the assessment of
potential adaptive reuse, and to weigh the importance of the evaluation outcomes based
on the opinion of experts and potentially other stakeholders involved. In this respect,
therefore, once the alternatives have been identified and the different categories have
been evaluated, the final step is to develop a weighting scheme w aiming to
accommodate the comparisons of alternatives. In the present research, these are obtained
from an experts’ opinion survey1, and are the following:
0.34, 0.30 and 0.36
EC S
ww w== =
Subsequently, the following composite index, CI*(A), is computed for each alternative,
where:
() ECSCI A w TEI w TCI w TVI=× +× + × (6)
The composite index produced for each alternative assists in the decision making since it
allows for comparisons of different alternatives of environmental, economic and social
factors and reflects values in monetary terms which are weighted according to the
importance of each category. Naturally, the best alternative is the one with lowest score.
The lower the score is, the more environmental, economic and social respectful, the
alternative under consideration is. The weighted decision support tool (WDST) is
illustrated in Table 5.
14 E. Sfakianaki and K. Moutsatsou
Table 5 Weighted decision support tool (see online version for colours)
Decision support tool for demolition or adaptive reuse of existing buildings
Alternative 1 Alternative 2
Eco-costs
Eco-costs (initial)
Con/tion
phase
Eco-costs (materials)
Eco-costs (assembling
semi/finished materials)
Operating phase
Eco-costs (heating)
Eco-costs (cooling)
Eco-costs (ventilation)
Eco-costs (lighting)
Eco-costs (equipment and
appliances)
Eco-costs of
alternatives
Intervention
phase
Eco-costs (partial demolition)
Eco-costs (restoration)
Eco-costs (demolition)
Eco-costs (reconstruction)
Total environmental indicator (TEI)
Weighted factor WE
Weighted total environmental indicator (We × TEI)
Life cycle cost
LCC
Investment costs (I)
Capital replacement costs
(Repl)
Residual value (Res )
Energy costs (E )
Water costs (W)
Non-fuel operating,
maintenance and repair costs
(OM&R )
Other costs (O)
Total cost indicator (TCI)
Weighted factor WC
Weighted total cost indicator (WC × TCI)
Social value
Ranking range
0,1–0,3
Use value
Memory value
Historical value
Age value
Architectural value
Total ranking (R )
Total value indicator (TVI) = (Total environmental
indicator + Total cost indicator ) / 2 × R
Weighted factor WV
Weighted total value indicator
Composite index (CI)
A
decision support tool for the adaptive reuse 15
5 Applying the WDST for a housing project
The final stage of the methodology proposed is the actual implementation to a real-
project case study. To emphasise the applicability initially of the tool proposed and
subsequently the accuracy of results and ease of use, it was preferred to use the initial
cost calculations from a case study already examined (Bowie and Jahn, 2002). More
specifically, the case study concerns a complex of approximately 200 apartments, built in
the 1960s, owned by a Dutch housing association which is planning to start an
intervention project. The characteristic approach of such a project would be to conduct a
feasibility study concerning various options in order to support a final project definition.
Apart from selling the apartments, the seven types of possible interventions are presented
in Table 2. To retain focus, only the alternatives of extensive renovation and
redevelopment will be examined. For these strategies, investment costs (traditional and
eco-costs) have been estimated on an apartment basis.
Let us assume that extensive renovation is considered as Alternative 1 (i = 1) and new
construction is considered as Alternative 2 (i = 2). The assumptions made are illustrated
below:
• The eco-costs during the operation phase are not calculated and are omitted from the
tool because in both alternatives the initial eco-costs that occur during the operating
phase are the same and will not influence the final result.
• The energy, water, operating and maintenance costs are also the same and are
omitted in the total calculation of the cost section. The life cycle cost of the building
is the same in both alternatives until the time of intervention. The difference in the
total costs commences after the intervention phase. For this purpose, the costs that
will be calculated are the costs of demolition and reconstruction.
• In order to calculate the ranking for the social section, two scenarios have been used.
The first scenario refers to the ranking of one stakeholder (a) who is fond of the
renovation alternative while in the second scenario the same stakeholder examines
also the alternative of demolition and reconstruction.
The stakeholder defines the social-cumulative-value of the existing building in the
case that the decision is to adopt and reuse it even if the use value of the building
may not exist yet. In this case, the responsibility to retain the memory, historical,
architectural and age value of the building is of high importance. As such the ranking
factor R(a)1 is formed as follows:
(
)
111 1
11
()
0.7
R a UseValue MemoryValue HistoricalValue
AgeValue ArchitecturalValue
=++
++ =
∑
On the other hand, the same stakeholder due to functional, technological, social and
legal obsolescence decides to demolish and reconstruct the existing cell considering
that it is more important the ability of the building to fulfil all the user needs in the
future more than the preservation of the cultural heritage. During studying this
alternative the ranking factor R(a)2 adjusted as follows:
16 E. Sfakianaki and K. Moutsatsou
(
)
222 2
22
()
1.3
R a UseValue MemoryValue HistoricalValue
AgeValue ArchitecturalValue
=++
++ =
∑
Subsequently, the following composite index, CI*(A), is computed for each
alternative, and presented in the WDST.
Table 6 Weighted decision support tool for a housing project (see online version for colours)
Weighted decision support tool
Alternative 1 Alternative 2
Eco-costs
Eco-costs of
alternatives
Intervention
phase
Eco-costs (partial demolition) 1.200,00
Eco-costs (restoration) 25.700,00
Eco-costs (demolition) 3.000,00
Eco-costs (reconstruction) 67.800,00
Total environmental indicator (TEI) 26.900,00 70.800,00
Weighted factor WE 0,34 0,34
Weighted total environmental indicator (We × TEI) 9.146,00 24.072,00
Life cycle cost
LCC
Cost of partial demolition 2.800,00
Cost of restoration 105.000,00
Costa of demolition 12.500,00
Cost of reconstruction 135.000,00
Other costs (O) 17.000,00 19.500,00
Total cost indicator (TCI) 124.800,00 167.000,00
Weighted factor WC 0,30 0,30
Weighted total cost indicator (WC × TCI) 37.440,00 50.100,00
Social value
Ranking range
0,1–0,3
Use value 0,30 0,10
Memory value 0,10 0,30
Historical value 0,10 0,30
Age value 0,10 0,30
Architectural value 0,10 0,30
Total ranking (R ) 0,70 1,30
Total value indicator (TVI) = (Total environmental
indicator + Total cost indicator ) / 2 × R
53.095,00 154.570,00
Weighted factor WV 0,36 0,36
Weighted total value indicator (WC × TVI) 19.114,20 55.645,20
Composite index (CI) 65.700,20 129.817,20
The results of the WDST demonstrate that Alternative 1 (extensive renovation) has the
lowest score and thus it is the most environmental, economic and social respectful
proposal. In fact, extensive renovation is approximately 50% lower than the demolition
alternative.
Naturally, the outcomes of this application should be further tested to the sensitivity
of the weighted scheme applied. However is should be noted that in the specific case
study, the results of the different indicators are so dramatically different that even the use
of a very different weighting scheme could not have altered the final outcome of
A
decision support tool for the adaptive reuse 17
Alternative 1 being more favourable under the criteria set. This finding throws some light
to the discussion of the results and demonstrates that there are cases where the results are
not sensitive to the application of weights.
6 Conclusions
The building sector has been constantly evolving towards a sustainable built
environment. In this respect, it is clear that there is need for a tool that will take into
consideration the sustainability of buildings using three main areas: the environment, the
society and the economy. The number of abandoned buildings in Europe and in Greece in
particular is large making the need for intervention almost self-evident. The question that
rises in these cases is the type of intervention and the hypothesis set in this research is
whether re-use is a preferred option as opposed to demolition and reconstruction of these
buildings. This issue needs serious consideration since there are a series of social,
cultural, economical, and environmental reasons to be reserved about demolition on a
wide scale. Adaptive reuse of old buildings has brought long and short-term benefits to
cut the environmental, social and economic costs of urban development and expansion in
a sustainable manner.
The decision-making tool that has been presented in this paper examines not only
environmental issues but economic and social factors aiming to embrace all three sections
of sustainable development. A number of methods and case studies have been examined
that fed and assisted the development of the WDST. Ultimately, its aim is to assist the
decision-making process for the pertinent parties enabling comparisons of different
indicators in common monetary units. This allows a quick and easy comparison between
alternatives and options as demonstrated herein. The tool at present stage is by no means
exhaustive and more thorough and in-depth examination of the impacts of environmental,
social and economic indicators on the level of intervention on a building is required. The
next stage should also include more applications of the tool to real projects enabling the
testing, monitoring and auditing of the outcomes and fine tuning of the tool.
References
Allen, D. (2009) Memory and Place: Two Case Studies [online] http://places.designobserver.com/
(accessed 20 June 2012).
Bowie, R. and Jahn, A. (2002) The New Directive on the Energy Performance of Buildings,
European Commission, Directorate General for Energy & Transport, Brussels, Belgium.
Bragança, L., Koukkari, H., Veljkovic, M. and Borg, R.P. (2010) ‘Sustainable construction – a life
cycle approach in engineering’, in COST Action C25. International Symposium, Faculty for
the Built Environment, University of Malta, Malta.
Brochner, J., Ang, G. and Fredriksson, G. (1999) ‘Sustainability and the performance concept:
encouraging innovative environmental technology in construction’, Building Research &
Information, Vol. 27, No. 6, pp.367–372.
Bullen, P.A. (2007) ‘Adaptive reuse & sustainability of commercial buildings’, Facilities, Vol. 25,
Nos. 1/2, pp.20–31.
Cole, R.J. (1998) ‘Emerging trends in building environmental methods’, Building Research &
Information, Vol. 26, No. 1, pp.3–16.
18 E. Sfakianaki and K. Moutsatsou
Cole, R.J. (1999) ‘GBC 2000. Changes to the GBC framework and GB tool’, Report submitted to
the Buildings Group/CETC, Natural Resources, Canada, 31 March.
Cole, R.J. (2005) ‘Building environmental methods: redefining intentions’, Building Research &
Information, Vol. 35, No. 5, pp.455–467.
Crawley, D. and Aho, I. (1999) ‘Building environmental assessment methods: environmental’,
Building Research & Information, Vol. 27, Nos. 4/5, pp.300–308.
Davidson, M. and Dolnick, F. (2004) ‘A planner’s dictionary’, Planning Advisory Service Report
Nos. 521/522.
de Jonge, T. (2005) Cost Effectiveness of Sustainable Housing Investments, Dissertation ed. DUP
Science, Delft.
de Jonge, T. (2006) ‘The eco-costs of housing transformation’, in Gruis, V., Visscher, H. and
Kleinhans, R. (Eds.): Sustainable Neighborhood Transformation, pp.133–148, IOS Press,
Amsterdam.
DOE (1996/2006) Baseline Environmental Management Report [online]
http://www.em.doe.gov/bemr/BEMRPages/execsum96.aspx (accessed 21 June 2012).
Douglas, J. (2006) Building Adaptation, Butterworth/Heinemann, Oxford.
Feilden, B.M. (1982) Conservation of Historic Buildings, Butterworth & Co., Oxford.
Haapio, A. and Viitaniemi, P. (2008) ‘A critical review of building environmental assessment
tools’, Environmental Impact Assessment Review, Vol. 28, pp.469–482.
Hartless, R. (2003) ‘Application of energy performance regulations to existing buildings’, Final
report of the Task B4, ENPER TEBUC Project, SAVE 4.1031/C/00-018, Building Research
Establishment, Watford, UK.
IEA Annex 31 (2001) ‘Assessing the adaptability of buildings’, in Russell, P. and Moffatt, S.
(Eds.): Energy-Related Environmental Impact of Buildings.
Itard, L.C.M., Klunder, G. and Visscher, H. (2006) Environmental impacts of renovation, in
Gruis, V., Visscher, H. and Kleinhans, R. (Eds.): Sustainable Neighborhood Transformation,
pp.113–129, IOS Press, Amsterdam.
Kishk, M., Al-Hajj, A., Pollock, R., Aouad, G., Bakis, N. and Sun, M. (2003) Whole Life Costing in
Construction: A State of the Art Review, RICS Foundation, London.
Kohler, N. and Moffatt, S. (2003) ‘Life-cycle analysis of the built environment’, UNEP Industr.
Environ., Vol. 2, No. 3, pp.17–21.
Langston, C., Wong, F., Hui, E. and Shen, L.Y. (2008) ‘Strategic assessment of building
adaptive reuse opportunities in Hong Kong’, Building and Environment, Vol. 43, No. 10,
pp.1709–1718.
Larsson, N. and Cole, R.J. (2001) ‘Green building challenge: the development of an idea’, Building
Research and Information, Vol. 29, No. 5, pp.77–88.
Norris, M. and Shiels, P. (2004) ‘Regular national report on housing developments in European
countries’, Synthesis Report for ‘the Housing Unit, Dublin, Ireland.
Power, A. (2008) ‘Does demolition or refurbishment of old and inefficient homes help to
increase our environmental, social and economic viability?’, Energy Policy, Vol. 36, No. 12,
pp.4487–4501.
Reijnders, L. and Roekel, A. (1999) ‘Comprehensiveness and adequacy of tools for the
environmental improvement of buildings’, Journal of Cleaner Production, Vol. 7, No. 3,
pp.221–225.
Retzlaff, C.R. (2009) ‘Green buildings and building assessment systems’, Journal of Planning
Literature, Vol. 24, No. 1, pp.3–21.
Riegl, A. (1982) ‘The modern cult of monuments: its character and its origin [1903]’, Oppositions,
Fall, Vol. 25, pp.21–51.
Roders, P.A. (2006) ‘A tool for architects, built and human environment’, 6th International
Postgraduate Research Conference, Delft University of Technology.
A
decision support tool for the adaptive reuse 19
Schade, J. (2007) ‘Life cycle cost calculation models for buildings’, in Atkin, B. and Borgbrant, J.
(Eds.): Proceedings of 4th Nordic Conference on Construction Economics and Organisation:
Development Processes in Construction Management, Luleå tekniska universitet, pp.321–329.
Sleight, C. (2005) ‘Construction growth expected to increase’, International Construction,
Vol. 44, No. 1, pp.12–13.
Sieglinde, F. (2010) Life-Cycle Cost Analysis (LCCA), National Institute of Standards and
Technology (NIST) [online] http://www.wbdg.org/resources/lcca.php (accessed 28 June
2010).
Smullen, J. and Hand, N. (2005) A Dictionary of Finance and Banking, Oxford University Press
[online] http://www.oxfordreference.com/views/ENTRY.html?subview=Main&entry=t20.
e2493 (accessed 28 February 2011).
Thomsen, A. and van der Flier, K. (2008) ‘Replacement or reuse? The choice between demolition
and life cycle extension from a sustainable viewpoint’, in Norris, M. and Silke, D. (Eds.):
Shrinking Cities, Sprawling Suburbs, Changing Coutrysides, ENHR Conference 2008, Centre
for Housing Research, Dublin.
United Nations Environmental Programme (UNEP) (2007) United Nations Environmental
Program-UNEP 2007 – Annual Report [online]
http://www.unep.org/PDF/AnnualReport/2007/AnnualReport2007_en_web.pdf (accessed
31 July 2013).
Vogtländer, J.G. (2001a) ‘The virtual eco-costs ‘99 – a single LCA-based indicator for
sustainability and the eco-costs-value ratio (EVR) model for economic allocation’,
International Journal of LCA, Vol. 6, No. 3, pp.157–166.
Vogtländer, J.G. (2001b) The model of the Eco-costs/Value Ratio, a New LCA Based Decision
Support Tool, PhD thesis, Delft University of Technology, DfS, Delft.
Wallhagen, M. and Glaumann, M. (2011) ‘Design consequences of differences in building
assessment tools – a case study’, Building Research & Information, Vol. 39, No. 1, pp.16–33.
Notes
1 68 Greek experts (i.e., designers, engineers developers and building users) participated in a
survey undertaken by the authors. 39% of the respondents are engineers (17% architects, 22%
civil engineers) each of which had a minimum of five year work experience being involved in
more than three restoration projects; 29% are developers and 32% building users (20%
building owners and 12% building occupants).
