Design-Build Projects: a Comparison of Views Between South Australia and Singapore
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CIB World Building Congress, April 2001, Wellington, New Zealand Page 1 of 11 Paper: CLI 36 DESIGN-BUILD PROJECTS: A COMPARISON OF VIEWS BETWEEN SOUTH AUSTRALIA AND SINGAPORE Y Y LING1, S LOK1 AND E S M TAN2 1Department of Building, National University of Singapore, Singapore 119260 2PWD Corporation Pte Ltd, Singapore 069110 ABSTRACT One of the ways to increase construction productivity is to use the design-build (DB) procurement method. DB is said to foster an integrated approach to construction, and may be able to solve some of the fragmentation problems faced by the construction industry today. In Australia, DB plays a crucial role in increasing efficiency of the construction industry. As such, countries with low construction productivity, such as Singapore, have much to learn from Australia. A research was undertaken in South Australia to gauge the performance of DB projects with respect to time, cost and quality. Investigation was also carried out on the appropriateness of using DB for projects of different nature and on whether there is any major change in the architect’s role in DB projects. Questionnaire surveys were carried out to gather opinions of architects and contractors in South Australia. Purposive sampling of architects and contractors was adopted. In depth discussion of the views gathered was undertaken, and the results were compared to previous studies carried out in Singapore. The areas of comparison between the performance of DB projects in Singapore and Australia are: aesthetic quality, workmanship quality, physical construction time, total development time, timeliness of completion and costs. Conclusions were then drawn from the comparison. Statistical analysis was also undertaken to ascertain the nature of project that is suitable to use the DB procurement method, such as buildings that are simple, complex, innovative, standardized, large, medium and small sized and in new construction or in renovation works. A list of project nature was then produced, so that clients can use it as a checklist, in deciding whether their projects are suitable to make use of the DB procurement route. Similar statistical analysis was also carried out to ascertain the importance of contractors’ contribution and to investigate any change in the architects’ roles in the design and construction stages in DB projects. Survey results were compared to studies carried out in Singapore and conclusions drawn. KEYWORDS: Design-build; Singapore; Australia; Performance; Procurement INTRODUCTION In design-build (DB) procurement system, design and construction become the responsibility of one organisation, usually a contractor (Janssens, 1991; Masterman, 1992). This procurement route enables clients to employ one firm that takes sole responsibility for delivering the required building and associated services in accordance with defined standards and conditions (Bennett et al., 1996). CIB World Building Congress, April 2001, Wellington, New Zealand Page 2 of 11 Paper: CLI 36 The first objective of this paper is to investigate the performance of DB projects in South Australia, with respect to time, cost and quality. This is then compared to the performance of DB projects in Singapore. The next objective is to investigate the types of project characteristics that best suit DB procurement method. In particular, the study investigated whether projects that are simple, complex, innovative, standardized, large, medium and small sized and whether projects that are new construction or renovation works are suitable for DB procurement system. The final objective of the paper is to investigate whether there is any major change in the architect’s role in DB projects. This is because, unlike the traditional design-bid-build (DBB) arrangement, architects are now engaged by contractors, instead of the project owner, to undertake the design. The importance of this study is that if it is found that DB projects have good time, cost and quality track records, more projects should be procured based on this method. Secondly, a list of project nature were produced, so that clients can use it as a checklist, in deciding whether their projects could use the DB procurement route. By knowing whether the architects’ roles have changed, architects who are new to DB projects would know what to expect and tailor their services to the new requirements. PERFORMANCE OF DB PROJECTS Quality of DB projects A report by Bennett et al. (1996) showed that quality targets for DB projects were lower and less frequently met compared to DBB projects. Akintoye and Fitzgerald (1995) found that architects felt that quality of product and design innovation are sacrificed in the use of DB. However, a study by the USA Construction Industry Institute (Krizan, 1997) found that there are no significant differences in quality among DB, DBB and management form of contract procurement. The NEDO report (1985) also concluded that though traditional methods of contracting are good, alternative forms, such as DB, produce quicker results at competitive prices and with no resulting loss in quality. Konchar and Savindo (1998) discovered that DB projects achieved equal if not better quality results than other types of projects. Given these differing views, the fieldwork would investigate Australian architects and contractors’ view Time performance of DB projects A study by Akintoye and Fitzgerald (1995) showed that 54% of the clients thought that DB offered savings in construction time and 44% estimated the average time saved to be 1 - 15%. In the survey of construction contractors, 54% of respondents claimed that the use of DB can achieve up to 20% reduction in overall project time compared to the traditional approach (Akintoye, 1994). Konchar and Sanvido (1998) found DB to be at least 12% faster than DBB projects. Similarly, in a survey done by Ndekugri and Turner (1994), an overwhelming majority of respondents indicated that DB is generally faster than the traditional method. In Singapore, a study by the Construction Industry Development Board (CIDB, 1994) showed that three quarters of the respondents surveyed achieved time saving of 5 to 30 % by using DB. Case studies of the ISK Warehouse and Kranji Secondary School in Singapore also showed that DB helped the projects to be completed within a short time span (CIDB, 1994). From the various views of researchers on the time performance of DB projects, it can be concluded that one of the main advantages of DB is time saving. The validity of this is investigated in the fieldwork. CIB World Building Congress, April 2001, Wellington, New Zealand Page 3 of 11 Paper: CLI 36 Cost performance of DB projects Ndekugri and Turner (1994) noted that the DB approach is amenable to the stipulation of a maximum guaranteed price and hence for a client with an overriding concern on costs, the DB approach provides better protection than traditional system. Pain and Bennett (1988) concluded from case studies that cost of DB projects may be the same as DBB projects, and may be even lower. The surveys by Akintoye & Fitzgerald (1995) and Akintoye (1994) found that 53% of architects and 76% of contractors claimed that DB could achieve savings in construction cost. Konchar and Sanvido (1998) discovered from their studies that DB projects to be at least 6.1% cheaper than DBB projects. A study by the USA CII (Krizan, 1997) showed that DB projects had significantly less cost growth than DBB projects and somewhat less cost growth than projects utilising construction management approach. Songer and Molenaar (1996) attributed the cost reduction to the shortening of project duration and the introduction of the contractor’s construction knowledge in the design. However, there are studies that showed that DB projects may not be cheaper than DBB projects. The largest industrial client in Singapore, the Jurong Town Corporation, found that their DB projects were slightly more expensive as compared to conventional projects (Chong, 1998). A majority of architects in Akintoye and Fitzgerald’s (1995) study attributed the cost savings to reduced standards and lower professional fees. The fieldwork would study the professionals’ views on cost aspects of DB projects. PROJECT CHARACTERISTICS SUITABLE FOR DB Bennett and Flanagan (1983) suggested that DB is only suitable for ‘simple well defined or standard buildings’. Many authors have given suggestions on the types of projects that are suitable for DB (NEDO, 1983; Franks, 1990; Naoum, 1991). The studies generally showed that there is no one ‘best’ procurement system for building projects and the correct arrangement depends on the particular set of project circumstances, type of owners, their time and cost requirements and the characteristics of the projects (Nahapiet and Nahapiet, 1985). In view of the different opinions encountered, it is difficult to conclude what types of projects are suitable for DB procurement system. As such, the fieldwork to investigate this aspect of DB was mounted. ROLE CHANGE IN DB PROJECTS In the traditional DBB arrangement, two separate groups are involved; the design group and the construction group (Mohsini and Davidson, 1992). In DB projects however, the contractors are now involved very early in the design. The contractor’s early involvement allows truly collaborative decision-making which fosters innovative solutions (Yates, 1995). Innovation is encouraged in DB projects because contractors have control over the design (Pain, 1993), can reap financial rewards from the use of innovative products and processes (Pain, 1993), and have the opportunity to improve quality and provide more cost- effective solutions (Songer et al., 1994). With the increasing complexity of buildings, potentially appropriate techniques can be mobilised by suppliers and specialist contractors and DB provides access to this knowledge during the design stage (Kluenker, 1996). In the fieldwork, the importance of the contractors’ contribution and the frequency of accepting their contributions are investigated. The roles of architects are also expected to change in DB projects. In DBB projects, architects are generally the leader of the team. In DB projects however, the line of authority may be reversed.