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Improving Ecological Performance of Industrialised Building Systems in

Malaysia

Abstract

For construction stakeholders to fully embrace sustainability, its long benefits and associated

risks need to be identified through holistic approaches. Consensus among key stakeholders is

very important to the improvement of the ecological performance of Industrialised Building

Systems (IBS), a building construction method gaining momentum in Malaysia. A

questionnaire survey examines the relative significance of 16 potentially important

sustainability factors for IBS applications. To present possible solutions, semi-structured

interviews solicit views from experienced IBS practitioners, representing all of the

professions involved. Three most critical factors agreed by key stakeholders are material

consumption, waste generation and waste disposal. Using SWOT analysis, the positive and

negative aspects of these factors are investigated; with action plans formulated for IBS design

practitioners. The SWOT analysis based guidelines have the potential to become part of IBS

design briefing documents against which sustainability solutions are contemplated, selected

and implemented. This research extends existing knowledge on ecological performance

issues by considering the unique characteristics of IBS and identifying not only the benefits,

but also the potential risks and challenges of pursuing sustainability. This is largely missing

in previous research efforts. Findings to date in this research focus on providing much needed

assistance to IBS designers, who are at the forefront of decision making with a significant

level of project influence. Future work will move towards other project development phases

and consider the inherent linkage between design decisions and subsequent sustainability

deliverables in the project lifecycle.

Keywords: Industrialised Building System, sustainability, ecological, decision support,

Malaysia.

Article type: Research paper

Introduction

Industrialised Building Systems (IBS), also known as prefabrication, employ a combination

of ready-made components in the construction of buildings. IBS applications can improve the

quality of production, simplify construction processes and minimise waste generation

(Construction Industry Development Board, 2005; Blismas et al., 2006; Shen et al., 2009). Its

unique characteristics, such as offsite production and standardisation of components and

design using modular coordination, have great potential to enhance construction

sustainability (Jaillon and Poon, 2008; Hamid and Kamar, 2011). It will also help improve

work productivity, which has been a longstanding concern in the building industry. The

Malaysian government is urging the building industry to shift from traditional practices to

IBS based construction. Charting the future directions of local industry, the Construction

Industry Master Plan (CIMP) of Malaysia, specifically highlights government strategies for

IBS implementation (Construction Industry Development Board, 2006). To assess IBS-

related issues at the project level, the IBS Centre was set up in January 2007.

Despite top-level advocacy, the take-up rate of IBS in the Malaysian construction industry is

still low compared to developed countries such as the United Kingdom, Germany, the United

States of America and Japan. Previous literature reported the percentages of IBS usage in

Malaysia at only 10-15% of the overall volume of work during 2003 and 2006, while other

countries are easily double that (Hamid et al., 2008; Nawi et al., 2011; Kamar et al., 2009).

Polat (2010) observed that the level of IBS implementation is very low in developing

countries because the technological dependency. Moreover, the majority of key stakeholders

in Malaysia may have limited understanding and perhaps misconceptions on the potential of

IBS. They are often poorly informed on IBS design, unable to foresee its benefits and

unaware of its relevance to sustainability (Yunus and Yang, 2012). Current IBS practices also

exhibit an apparent lack of focus and linking to sustainability. This needs to be rectified to

achieve the full potential of IBS.

Sustainability considerations have expanded the scope of the construction industry by setting

a higher expectation in delivering building and infrastructure projects. An integrated

approach with a broader perspective is vital to encourage cooperation of the key stakeholders

in delivering a building with limited resource consumption, carbon reduction and biodiversity

targets in mind (Yang, 2012). Moreover, environmental concerns are best addressed on a

community scale which involves industry players at the project level (Cole, 2011).

Sustainability initiatives also require early collaboration among stakeholders (Horman et al.,

2006; Jaillon and Poon, 2010; Yang and Lim, 2008). Therefore, a consensus among key

stakeholders in setting the mutual prospective and agreeable targets of sustainability prior to

schematic design, is crucial for sustainable IBS delivery.

Cole (2004) stated that conventional methods of evaluating environmental performance need

to adopt new approaches that employ a broader range of considerations, while being

respectful of simplicity and practicality to make them more widely accessible. Decision tools

that are capable of encapsulating sustainability principles, including environmental

performance in the IBS design stage, will help optimise building components and ensure they

perform the intended functions. Luo et al., (2008) highlighted that inconsistent, inappropriate

and wrong decisions will affect the performance of IBS buildings. Effective decision making

is mandatory in eliminating construction problems such as change orders, delays in

production or construction and budget overrun, during IBS implementation (Chen et al.,

2010a).

This paper discusses findings of an ongoing study aimed at formulating decision making

guidelines that promote the ecological performance of IBS applications through exploring

critical factors relating to sustainable construction and operation of IBS building products.

Using feedback from experienced practitioners in local industry, current industry concerns

and critical issues have been identified. Through questionnaire surveys, this paper focuses on

the exploration of potential factors affecting IBS ecological performance during the design

phase of a project. Interview surveys and subsequent statistical analysis established a

consensus between key stakeholders regarding their views on making effective design

decisions. A decision-making strategy is then formulated using SWOT (Strengths,

Weaknesses, Opportunities and Threats) analysis for the identified factors and issues.

Literature Review

Sustainable development is becoming an essential part of human activity in terms of

providing quality of life while preserving resources for future generations. The level of

sustainability integration in built environment activities is increasing because of rapid

expansion in information, technology and product development (Jaafar et al., 2007; Yang,

2012). The construction industry requires holistic decision-making and innovative solutions

to enhance sustainability while realising mutually beneficial outcomes for all stakeholders.

With the support of information technology (IT), integration strategies and approaches will

help overcome industry fragmentation. However, the absence of a common language and

consensus among stakeholders is preventing full consideration of sustainability, especially

from environmental perspectives.

Kibert (2008) highlighted the seven principles of sustainable construction as 1) reduce

consumption of resources (reduce), 2) reuse resources (reuse), 3) use recyclable resources

(recycle), 4) protect nature (nature), 5) eliminate toxics (toxics), 6) apply life cycle costing

(economics), and 7) focus on quality (quality). These principles are provided as a benchmark

for creating a better world for future generations.

Ecological performance is the promotion of any attributes that will increase the ability of IBS

construction to preserve natural resources and reduce negative impacts on the environment. It

is necessary to ensure environment sustainability (Figge and Hahn, 2004; Jaillon and Poon,

2008). For example, improvements in IBS component quality will help ensure consistent

standards of insulation and reduce operational energy. Moreover, IBS offers major benefits in

the environmental sphere, such as material conservation and reductions in waste and air

pollution. This has been proven by several researchers such as Jaillon et al. (2009), Baldwin

et al. (2009) and Tam et al. (2007). Many IBS components are locally manufactured using

local products in reusable mouldings or assembly lines. This significantly reduces

transportation costs and traffic congestion. Moreover, construction waste can be minimised

and waste from off-cut is immediately recycled. By understanding the IBS potentials in

placing the environment as a priority, designers and consultants will be able to explore issues

of significance to ecological degradation. Table 1 lists a total of sixteen ecological

performance factors in IBS applications which have been identified from previous literature

reviews.

Table 1: Potential of ecological performance factors in IBS applications

No. Sustainability Factors Source

1 Waste generation Burgan and Sansom (2006)

Richard (2006)

Jaillon and Poon (2008)

Chen et al. (2010a)

Teo and Loosemore (2003)

Tam et al. (2007)

No. Sustainability Factors Source

Arif and Egbu (2010)

2 Ecology preservation Adetunji et al. (2003)

Al-Yami and Price (2006)

Burgan and Sansom (2006)

Shen et al. (2007)

Soetanto et al. (2004)

3 Energy consumption in design and

construction

Holton (2006)

Abidin and Pasquire (2005)

Nelms et al. (2007)

Shen et al. (2007)

Burgan and Sansom (2006)

International Council for Building Research and

Innovation (1999)

Chen et al. (2010a)

4 Embodied energy Department of Trade and Industry (DTI) (2001)

Ian et al. (2008)

5 Waste disposal Holton (2006)

Tam et al. (2007)

Soetanto et al. (2004)

6 Health of occupants (indoor air

quality)

Al-Yami and Price (2006)

Gibberd (2008)

Chen et al. (2010a)

7 Material consumption Chen et al. (2010a)

Gibberd (2008)

Holton (2006)

Luo et al.(2005)

Nelms et al. (2007)

Taher et al. (2009)

Jaillon and Poon (2008)

8 Recyclable / renewable contents Chen et al. (2010a)

9 Site disruption Burgan and Sansom (2006)

Chen et al. (2010a)

Gibb and Isack (2003)

Gorgolewski (2005)

10 Transportation and lifting Blismas and Wakefield (2009)

Department of Trade and Industry (DTI) (2001)

Luo et al. (2008)

Patzlaff et al. (2010)

Yee (2001)

Zhao and Riffat (2007)

Song et al. (2005)

Gorgolewski (2005)

11 Land use Adetunji et al.(2003)

Al-Yami and Price (2006)

Burgan and Sansom (2006)

International Council for Building Research and

Innovation (1999)

Shen et al. (2007)

12 Reusable / recyclable elements Song et al. (2005)

13 Operational energy Department of Trade and Industry (DTI) (2001)

Chen et al. (2010a)

14 Water consumption Adetunji, et al.(2003)

Al-Yami & Price (2006)

No. Sustainability Factors Source

Gibberd (2008)

Holton (2006)

Nelms et al. (2007)

Chen et al. (2010a)

15 Environment administration Adetunji et al. (2003)

Ian et al. (2008)

16 Pollution generation Shen et al. (2007)

Shen et al. (2010)

Chen et al. (2010a)

Research Gap

Most of the current IBS implementation isolates the design and construction processes (Nawi

et al., 2011). The implementation is often design oriented, cost focused and project delivered

without specific consideration of maximizing the advantages IBS brings. The conventional

approach in IBS applications also hindered cooperation among key stakeholders (Hamid and

Kamar, 2011; Nadim and Goulding, 2011; Nawi et al., 2011). There is a lack of

communication and cooperation among the key stakeholders known as “over the wall”

syndrome (Evbuomwan and Anumba, 1998). In these conventional approaches,

manufacturers and contractors can only become involved after the design stage. The lack of

integration will result in problems for the supply chains such as delays, under or over supply

and constructability issues. The need for subsequent re-design and re-planning will increase

project costs (Hamid et al., 2008). It is important to allow each stakeholder to define issues

and set sustainability goals prior to schematic design and then continue through construction,

operation and demolition of the building.

In addition, little concern has been given to improving sustainability in the early stage of

construction, especially when the designer prepares the drawings and specifications (Ding,

2008). Contrary to the IBS implementation approaches, most of the available assessment

guidelines and tools are not design-oriented. They were constructed to endorse or disapprove

a final design therefore cannot serve the purpose for designers to contemplate alternatives

(Soebarto and Williamson, 2001). In Indonesia for example, professional designers and

contractors are engaged in separate contracts, which means the contractors only get involved

after the designs are completed (Trigunarsyah 2004). This engagement style leads to isolation

and ignores opportunities in optimising project benefits such as cost savings and speedy

completion. Therefore, early involvement and cooperation among stakeholders is also very

important to improve sustainable IBS construction.

Environmental issues and financial considerations should be evaluated together in improving

sustainability. Some assessment tools, such as BREEAM and LEED, do not include financial

aspects in the evaluation framework (Ding, 2008). The other tools such as Green Star, Green

Mark, and Green Building Index also focus on the evaluation of design against a set of

environmental criteria such as energy and water efficiency, indoor environmental quality and

sustainable site management. The considerations on the financial aspects are neglected and

may lead to a project that, while environmentally sound, would be very expensive to build.

The challenge for the construction industry is to deliver economic buildings that maintain or

enhance the quality of life, while at the same time reducing the impact of the social,

economic and environmental burdens from the community.

Currently, the IBS Score System, which was developed by the Construction Industry

Development Board (CIDB) of Malaysia, is used to measure the usage of IBS. This tool

measures the percentage of IBS usage in a consistent way with a systematic and structured

assessment system (Construction Industry Development Board, 2005). In Malaysia, the

current assumption is that higher IBS scores mean more ‘sustainable construction’. In a way,

a higher score can indeed reflect a reduction of site labour, an improvement in quality, neater

and safer construction sites, faster project completion as well as lower total construction cost

(Construction Industry Development Board, 2005). However, it does not explicitly and

directly represent sustainability attributes (e.g., environment, social and economy) for IBS

applications. The assessment schemes focuses on the percentage of IBS components used in

the construction, such as precast concrete, component repeatability and design using modular

coordination concepts.

Elsewhere, researchers considered IBS in assessment tools such as PPMOF (Prefabrication,

Preassembly, Modularisation and Offsite Fabrication), IMMPREST (Interactive Method for

Measuring PRE-assembly and Standardisation), PSSM (Prefabrication Strategy Selection

Method) and CMSM (Construction Method Selection Model). PPMOF was a computerised

tool developed to assist industry practitioners in evaluating the applicability of IBS

components on their projects (Song et al., 2005). It focused solely on strategic level analysis.

Chen et al, (2010b) stated that decisions might be biased because of the weight assignment to

each category is subjective. IMMPREST, which was developed in the United Kingdom,

attempted to include sustainability elements for decision making (Pasquire et al. 2005).

However, it has several shortcomings in comprehensively evaluating sustainability (Luo et

al., 2008). The most significant challenge in using this tool is the lack of information at the

early stage of a project (Chen et al., 2010b). For successful early collaboration between the

design and construction teams, sufficient information is required to facilitate better

understanding and minimise misconception among teams. In the United States, PSSM was

developed to help a project team find a suitable prefabrication strategy for a building system.

The solution was formulated through understanding the synergies and issues with IBS

strategies, building processes and building performance early in the design phase, but it only

focused on curtain wall systems, mechanical systems and wall frames (Luo et al., 2008). The

latest tool, CMSM was specifically designed for concrete building projects to select and

optimise IBS components (Chen et al., 2010b).

While these existing tools provide sound benchmarks in the selection of IBS, they are not

able to make effective recommendations on how to improve sustainability based on the

chosen options. As highlighted by Ofori and Kien (2004), the absence of relevant information

to guide designers hinders the incorporation of sustainability into holistic IBS designs and

delivery. This is the crux of the issue in the application of IBS in Malaysia. It is important to

provide design professional with appropriate guidance at the project level.

Blismas et al. (2006) stated that most of the decision tools for assessing IBS applications

focus on economic issues. They often disregard ‘softer’ issues which are perceived as

insignificant, such as lifecycle prediction, health and safety and the effects on energy

consumption. There is a need to establish holistic methods of IBS selection by considering

Triple Bottom Line (TBL) criteria and responding to institutional implications in order to

improve overall IBS implementation. As discussed in the previous section, IBS applications

tend to be linked with government projects primarily. As such, political scenarios and

government support are very important aspects. This research explores the environmental,

economical and social aspects of IBS and extends sustainability assessment to include

‘technical quality’ and ‘implementation and enforcement’ aspects. However, in this paper, the

focus is on ecological performance in enhancing sustainability for IBS applications.

Developing and developed countries may have different priorities in terms of IBS

applications in terms of the type of IBS, characteristics of local communities and available

resources. IBS in Malaysia also consists of structural applications, such as timber and steel,

which exhibit unique characteristics for the improvement of sustainable deliverables (Burgan

and Sansom, 2006). Most of the tools presented to date only reflect scenarios of developed

countries. Local and regional characteristics and physical environment are among the

important elements to be considered when measuring the level of sustainability. With the

flexibility for adaptation, issues studied in developed countries are unlikely to be applicable

or even relevant to developing countries (Cohen, 2006).

Therefore, there is a need to identify critical issues and provide solutions to local problems.

Exploration on the benefits, potential risks and challenges of pursuing sustainability can lead

to a holistic view in decision-making. With unified views and agreements between key

stakeholders, a consensus in encapsulating sustainability strategies can be achieved.

Research Approach

Creswell (2009) named four different views of research paradigms as “postpositivist”, “social

constructivist”, “advocacy and participatory” and “pragmatic” worldviews. Each view

represents the cluster of beliefs and perspectives a researcher should hold within a scientific

discipline (Bryman, 2004). This research is oriented towards solving practical industry

problems and concerns on local sustainability development. The most applicable

philosophical position and orientation towards the inquiry for this research is pragmatism.

The focus of this approach is not the theory, but the research problems. The solution can be

established by deriving knowledge regarding the problem, which arises from actions,

situations, and consequences. Pragmatism often demands mixed methods to solve research

problems (Creswell 2009). Several research mechanisms are integrated to ensure the success

of this project, including questionnaire surveys, semi-structured interviews, SWOT analysis

and the development of decision-making guidelines.

The unit of analysis refers to the type of unit a researcher uses when measuring and the

aggregation level of data during subsequent analysis (Neuman, 2007). The common units of

analysis are the individual, the group (e.g., family, friendship group), the organisation (e.g.,

corporation, company), the social category (social class, gender, race), the social institution

(e.g., religion, education) and the society (e.g., nation, a tribe). In this study, the unit of

analysis used is the organisation. Data was collected from different organisations such as

contractors, designers and manufacturers. It was analysed by comparison and synthesis to

extract findings and facilitate discussion on the subjects investigated.

From the literature review of existing decision making tools, 16 potentials factors have been

identified as capable of improving the ecological performance in IBS applications (Table 1).

These factors were included in a questionnaire survey instrument that was piloted before the

main survey investigation. It is important to compile survey questions into useable formats in

describing responses, comprehensiveness and acceptability of the questionnaire (Fellows and

Liu, 2008). At first, the questionnaire is used to identify critical factors in IBS applications

that are able to improve sustainability from environmental dimensions. A consensus among

key stakeholders is achieved by statistically analyzing the interrelationships between the

investigated factors. Later, semi structure interviews were used to gather information

regarding agreeable strategies and practical solutions.

SWOT (strengths, weaknesses, opportunities, and threats) analysis was employed in this

research. SWOT can evaluate the internal and external conditions simultaneously by

recording all of the possibilities and opportunities. As a result, through a systematic approach,

support for a decisive situation can be achieved (Srivastava et al., 2005). This analysis has an

advantage in that it presents holistic, rather than ‘preferred’, views regarding sustainable

deliverables for IBS application. It also can provide a good basis for the formulation of

implementation strategies.

During the questionnaire survey, a total of 300 questionnaires were distributed to potential

respondents randomly selected using CIDB databases and other listings of Malaysia

construction industry organisations. To ensure a maximum level of response rate, a

combination of hard copy mail out, online survey, and face-to-face consultation was

employed. As a result, 115 valid questionnaires were received and used in the analysis,

representing a response rate of 38%. In the questionnaire, the respondents were asked to

assign an appropriate rating on a five-point scale where 1 is “very insignificant”, 2 is

“insignificant”, 3 is “neutral”, 4 is “significant”, and 5 is “very significant”. The formula used

to calculate the mean score rating is:

( ) ( ) ( ) ( ) ( )

( )

(1)

A t-test was used to identify the most significant factors among those selected. This method

was previously proven by several researchers such as Ekanayake and Ofori (2004) and Wong

and Li (2006) in related studies. In this research, the null hypothesis (factors were neutral,

insignificant, and very insignificant) is accepted if the t-value is smaller than 1.6583 (the

critical t-value).

It is also important to consider the differing views between each organisation type regarding

the factors significant to improving the IBS ecological performance. Non-parametric testing

was applied in this study because the variables were measured by ordinal scale and not in

normal distribution. In order to assess how different types of organisations rate these factors,

the Kruskal-Wallis one-way analysis of variance (ANOVA) proves to be the most appropriate

for the problem on hand (Wong and Li 2006) therefore was used. The chi-square (χ2) was

interpreted as Kruskal-Wallis value representing the rating of sustainability factors across

respondents’ organisations. When the p-value is lower than 0.05, there will be significant

differences between views of organisation.

In the interview study, twenty interviewees from different types of organisations participated.

They were identified through CIDB recommendation based on their previous work, as well as

from the questionnaire study. All interviewees have more than 10 years of experience in the

Malaysian construction industry. The variety in the respondents’ backgrounds allows the

authors to identify different professional perceptions in pursuing sustainability.

Flexibility in the semi-structure interviews allowed the researchers to comprehensively

investigate and explore detailed information on each issue, while at the same time

maintaining focus on the research objectives. Subsequently, SWOT analysis was used to

provide a decision-making guideline. The data from the semi-structured interviews was

organised and transcribed before the data were keyed into QSR NVivo version 9. The

strengths, weaknesses, opportunities, threats and potential action plans were explored and

interpreted from the available coding. The interpretation process provided themes and

descriptions in formulating the SWOT based decision-making frameworks and guidelines.

Designers require lots of information to guide them in making appropriate decisions,

especially when integrating sustainability efforts (Ofori and Kien 2004). In project

management, SWOT analysis is able to help a decision maker decide what risks they need to

take in order to see the expected return on investment (Milosevic 2010). Lu et al. (2009)

adopted SWOT analysis as the basic methodology to gain insight into the internationalisation

of China’s construction companies in the global market. In Vietnam, Luu et al. (2008)

proposed a framework that integrates balanced scorecard and SWOT matrix to measure the

performance of construction firms in developing countries. SWOT analysis is ideal for

analysing the situation each investigated factor presents. The interrelated criteria also help to

develop potential strategies. Through such analysis, decision-makers can exploit new

opportunities by utilising available strengths, avoiding weaknesses and diagnosing any

possible threats in the examined issues. SWOT analysis can present a framework capable of

integrating potential sustainability factors into the equation while not being inflexible and

restrictive. It will be able to loosely bind issues together and provide adequate information

within the context of the subject matters for decision-making assistance. The outcomes will

then act as “guidance” documents for the designers to consider and contemplate sustainable

solutions in IBS applications. Any other type of frameworks will not suit the context of the

examined problems.

Further research work in this on-going study will utilise several case studies to assess the

appropriateness and level of efficiency of the developed decision tools.

Results and Analysis

Sampling is important in this study because it is rarely possible to examine an entire

population, which is largely due to the resource restriction in most studies. The objective of

sampling is to provide a practical means of enabling data collection and processing

components of research to be conducted while ensuring that the sample provides a good

representation of the population (Fellows and Liu, 2008). Based on the nature of the research,

cluster sampling was adopted to investigate different perceptions from various groups of

respondents.

Seven groups of respondents were identified as the key stakeholders in IBS application based

on their organisation type. The organisation types were design/consultancy, contractors,

manufacturing, user or facility management, property development/client, research/academic

institution and government authority/agency. Using official professional listings (for

example, from the Construction and Industry Development Board, Industrialised Building

System Centre, Green Building Index Malaysia) as a basis, the respondents’ backgrounds

were reviewed to assess their suitability for participating in the survey. This type of sampling

is called “purposive or judgmental sampling” (Neuman 2007). It is used to select participants

from the specialised population - in this case, those with experiences and knowledge in IBS

implementation. Abidin and Pasquire (2005) also adopt this strategy to select particular

settings, persons or events to study sustainability value chain problems.

The questionnaire consisted of four major parts. Part 1 captured the respondents’

demographic details such as their level of experience and background. Part 2 examined the

level of significance of potential factors in enhancing sustainability deliverables for IBS

construction. Part 3 investigated the impact of those potential sustainability factors in

providing a better future without neglecting present needs. In Part 4, the respondents were

asked to give additional comments or suggestions. Finally, the respondents were invited to

participate in the subsequent investigation phase ofthis research.

Analysis of the survey response data produced mean significance values for the sixteen

ecological performance factors ranging from 3.78 to 4.50. Table 2 shows that ten factors

scored mean values greater than 4.0 and the remaining six factors scored between 3.78 and

3.99. The standard deviations for this analysis show very good data accuracy as little

variation exists from the mean evaluated. Subsequently,a t-test was used to help the authors

to identify the most significant factors. Three factors are therefore identified as the most

significant in improving sustainability in the ecology performance dimension. They are waste

generation, waste disposal and material consumption.

The Kruskal-Wallis one-way analysis of variance (ANOVA) reveals that there was no

significant difference between various stakeholders for waste generation (p value 0.215) and

waste disposal (p value 0.215). However, material consumption (p value 0.005) shows slight

differences across key stakeholders. A possible reason for this may be that manufacturers and

users are typically involved only with the end product. Unlike other groups, they are not

certain about estimating material consumption, especially during the construction stages.

Waste generation was ranked first in the survey analysis (Table 2: mean value 4.50). Burgan

and Sansom(2006) highlighted that since IBS employs off-site manufacturing processes, it

has the potential to minimise waste through the entire building lifecycle. Jaillon et al. (2009)

identified waste reduction as one of the major benefits when using IBS compared with

conventional construction. Their analysis shows the average wastage reduction level was

approximately 52%. Therefore it is extremely important to minimise the source of waste

generation through IBS design and construction, and at the same time, alleviate the burden of

waste management.

Waste disposal is ranked as the second most important factor (Table 2: mean value 4.38). The

IBS manufacturing process allows for better management of the waste stream (Gorgolewski,

2004; Gorgolewski, 2005). Many off-site manufacturing plants have recycling facilities and

the integration of industrial ecological systems allows waste from one production process to

become a resource for the next. In addition, effective design will ensure that resources are

consumed efficiently and materials ordered strictly to standard sizes, thus minimising onsite

processing and off-cuts. Soetanto et al. (2004) stated that the disposal (i.e. demolition and site

clearance) costs can be minimised when adopting IBS applications.

The third most significant factor for ecological performance is Material consumption (Table

2: mean value 4.28). In Malaysia, the expansion of urban and industrial areas has caused

mineral resource sterilization through the encroachment upon existing mines and quarries,

therefore preventing exploitation of and access to new and undeveloped mineral resources

(Hezri and Hasan, 2006). Jaillon and Poon (2010) stated that replacing conventional

construction with IBS applications will help reduce material consumption. Similar findings

also highlighted by Tam et al. (2005) confirmed that material consumption can be

significantly reduced through IBS construction. In their study, savings achieved from

plastering and timber formwork alone counts to approximately 100% and 74-87%

respectively.

Table 2: Ranking Sustainability Factors Categorised in the Ecological Performance Criteria

Sustainability Factors Rank Mean Std.

Deviation

t-value

1 Waste generation 1 4.50 0.792 6.652

2 Waste disposal 2 4.38 0.838 4.828

3 Material consumption 3 4.28 0.785 3.837

5 Recyclable / renewable contents 4 4.12 0.974 1.352

5 Site disruption 5 4.10 0.868 1.181

6 Transportation and lifting 6 4.08 1.036 0.810

7 Reusable / recyclable elements 6 4.08 1.010 0.838

8 Ecology preservation 8 4.04 0.976 0.482

9 Water consumption 9 4.01 1.031 0.091

10 Embodied energy 9 4.01 0.940 0.100

11 Environment administration 11 3.99 0.911 -0.103

12 Pollution generation 12 3.96 0.972 -0.387

13 Health of occupants (indoor air

quality)

13 3.92 0.992 -0.853

14 Operational energy 14 3.83 1.051 -1.700

15 Energy consumption in design and

construction

15 3.80 0.888 -2.437

16 Land use 16 3.78 0.884 -2.661

The three most significant factors were further investigated through semi-structured

interviews. This allows the authors to explore details of each factor in depth and to identify

solutions or action plans to consider, encapsulate and improve sustainability in IBS

applications. In this investigation, SWOT (Strengths, Weaknesses, Opportunities, and

Threats) analysis is used to present information and encapsulate recommendations into a

practical tool.

Twenty respondents participated in the interview sessions. These respondents belonged to

seven types of organisations, namely designer/consultant companies, manufacturer

companies, contractor companies, user or facility management companies, client/developer

companies, research/academic institutions and authority/government agencies. With a

minimum of 10 years of experience in real world IBS applications, they are considered the

most knowledgeable and authoritative to provide recommendations in enhancing sustainable

deliverables. Table 3 presents the SWOT analysis results on ecological performance criteria.

Table 3: SWOT Analysis Results on Ecological Performance Criteria

Sustainability

Factor Strengths Weaknesses Opportunities Threats

Material

Consumption

IBS produce

very

minimum

waste (S1)

Efforts to sort

different type of

wastage are

required (W1)

Usage of

renewable

materials can

improve

recovery rates

(O1)

Waste

minimisation

decision

should be

agreed during

the design

stage (T1)

Able to

facilitate

separation of

waste

streams (S2)

Need to design

proper location

for waste

collection (W2)

Less virgin

materials are

used when

construction

waste is recycled

for another

project (O2)

Proper

planning and

checklist are

required (T2)

Easy to

separate

disposal to

different

types (S3)

Lack of

cooperation

from sub-

contractor (W3)

Potential to

be re-used

(S4)

Waste

Generation

No waste

(S1) Ineffective

planning cause

mass wastages

(W1)

Reduce

wrapping for

elements

delivered on site

(O1)

Require

proper

handling (T1)

Less debris

(S2) Required

precise

dimension and

measurement

for each

element (W2)

Prevent waste by

proper

maintenance

(O2)

Damage

during

transportation

and handling

(T2)

Exact

elements are

delivered to

site (S3)

Design with

whole-life cycle

in mind to

minimize waste

(O3)

Unfit problem

( T3)

Specify & use

reclaimed or

Sustainability

Factor Strengths Weaknesses Opportunities Threats

waste materials

in construction

(O4)

Recycled waste

(O5)

Waste Disposal

IBS produce

very

minimum

waste (S1)

Efforts to sort

different type of

wastage are

required (W1)

Usage of

renewable

materials can

improve

recovery rates

(O1)

Waste

minimisation

decision

should be

agreed during

the design

stage (T1)

Able to

facilitate

separation of

waste

streams (S2)

Need to design

proper location

for waste

collection (W2)

Less virgin

materials are

used when

construction

waste is recycled

for another

project (O2)

Proper

planning and

checklist are

required (T2)

Easy to

separate

disposal to

different

types (S3)

Lack of

cooperation

from sub-

contractor (W3)

Potential to

be re-used

(S4)

The internal and external conditions are evaluated simultaneously by recording all of the

possibilities and opportunities. In this research, group-wise analysis was used in SWOT. This

methodology was effective in providing factors and major objectives and to clarify unclear

issues by developing a consensus among stakeholders (Srivastava et al., 2005). As shown in

Table 3, the significant strengths for material consumption were IBS produce minimum waste

(S1), able to facilitate separation of waste streams (S2), easy to separate disposal to different

types (S3) and potential to be re-used (S4). These strengths were then linked with the

recommendation suggested in the semi-structured interviews. For example, S1 provides an

idea for stakeholders to adopt methods and technology with lesser demand on materials for

their project as one of the action plans. 3R (reduce, reuse and recycle) strategies can be a way

forward to achieve sustainable development in Malaysia (Hamid and Kamar 2011). Similar

analysis was applied to both positive and negative considerations of all critical factors. Table

4 shows the recommendations based on the complete analysis. The recommendations provide

step-to step actions for stakeholders at the project level for specific sustainability challenges.

Table 4: Recommendations in improving sustainability in IBS implementation

Sustainability Factors Recommendations: Actions Plan

Material Consumption

Promotes recycle materials and resources

Use local resources and materials

Examine the nature of the materials used

Regulation to use sustainable resources

Effective and optimum materials handling

Follow specification provided

Adopt less materials technology

Waste Generation

Precision in size and dimension

Proper handling

Higher penalty and tax executions

Design for the environmental impact

Planning efficiently

Waste Disposal

Stringent environmental regulations

Disposal management and requirements

Recycle and reuse approach

Team up with other builders to recycle

Discussion

Building production in a controlled environment offers numerous opportunities to improve

sustainability, such as minimising construction time, increasing quality of buildings,

enhancing occupational health and safety and reducing construction waste. The three most

significant factors in IBS ecological performance demonstrate the importance to manage

resources and waste. Effective planning for materials and waste minimisation is imperative.

IBS applications were proven to have the ability to reduce waste for both design and

construction phases (Jaillon et al., 2009). The adoption of IBS applications contributes to

both material conservation and waste reduction (Jaillon and Poon, 2008). Early consideration

in the design stage will contribute to waste avoidance through efficient use of construction

materials and the planning of production processes. It is important for IBS component

manufacturers to improve operations by ordering material precisely and on a just-in-time

basis, considering appropriate storage facilities and eliminating defects and damages.

Modular coordination of materials such as brick, timber or steel components should be

promoted to standardise components and minimise double handling and off-cuts.

Victoria’s Environment Protection Act (1970, s.1I) states that waste should be managed in

accordance with the following order of preference:

avoidance;

re-use;

re-cycling;

recovery of energy;

treatment;

containment;

disposal.

The identification of waste generation as the most critical factor in improving IBS application

echoes the notion that waste needs firstly to be avoided and its generation process properly

managed to achieve a sustainability objective.

The second most significant factor is waste disposal, also relating to the waste management

process. The factor is the least preferable solution in the above waste hierarchy. However,

this factor can contribute to sustainability by encouraging IBS stakeholders to develop

efficient strategies to dispose construction materials. Schultmann and Sunke (2007)

highlighted that the reduction of waste through the establishment of closed-loop material

flows alleviates sustainable development constraints. Methods and techniques in waste

disposal need to be strategized to allow stakeholders to take advantage of material recovery.

IBS applications allow systematic and coordinated dismantling of building components,

which can be reused at a different location. In this context, focus for the long term should be

on encouraging an effective waste disposal process. As shown in Table 3, cooperation among

the builders to promote recycling and reuse is very important. Involvement from all

participants at the project level is vital to achieving such an objective. In this study, local and

regional characteristics and physical environments are also among the important elements to

be considered.

A full understanding of the local resource availability and capacity is vital to ensuring that

material consumption issues are properly considered in IBS project delivery. The qualitative

analysis of this study has resulted in the recommendation of seven actions plans (Table 4).

These action plans present the main process and steps of working through each critical factor

to improve sustainability. With these plans, designers may follow consistent approaches

while responding to sustainability concerns from all stakeholders. Intensive evaluation of

applicable materials will help the government determine and control the balance between

import and export of construction materials and minimise material price fluctuation.

Initiatives of using local materials and recycling can serve as a catalyst for the local economy

and close the loop of resource regeneration. Technologies promoting reuse or long service

life, such as durable mouldings and formwork, can contribute to material consumption

efficiency.

Conclusion

With proven benefits, Industrialised Building Systems (IBS) can provide the right ingredients

to the construction industry’s response to sustainability challenges in Malaysia. Against rising

interests, existing IBS evaluation criteria and tools do not specifically relate to sustainability.

The improvement of IBS environmental performance needs to involve all participants such as

developers, designers, contractors and manufacturers; to agree upon and prioritise issues; and

to support design professionals as they exert major influences to the project outcome.

A systematic strategy to improve IBS ecological performance through decision support to the

design phase is presented. Three critical factors are identified to be material consumption,

waste generation and waste disposal. To provide a decision making frame suited to the

subject matters yet conducive to brainstorming, testing of alternatives, and contemplation of

pros and cons, SWOT analysis is used to present specific strategies of dealing with the

critical factors and provide practical guidelines for IBS designers. The research process also

helps raise the industry’s general awareness of sustainability and highlights the need to make

existing evaluation tools capable of responding to new issues. Issues unique to developing

countries, through the cases of Malaysia, are also given due consideration.

We need a holistic approach to respond to sustainability challenges in IBS implementation.

The approach should encompass the entire project development cycles. As the first step,

research to date has combined quantitative and qualitative analysis to develop potential

strategies for IBS design professionals to respond to, deal with, and maximise benefits from

the key factors of ecological performance. On-going work will validate and improve this

decision framework for design before moving to consider issues in the construction and

operational phases. It will be interesting to find out the inherent linkages between design

decisions and actual sustainability deliverables during other development stages.

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