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A rich variety of cost models is used in the world's construction industries. In countries exposed to British practice, the use of traditional bills of quantities is common. Elsewhere, bills of quantities may not be used at all. This paper briefly reviews the nature and purpose of cost models both in the UK and in south‐east Asia. It explains how the principle of cost‐significance can lead to a simplified method of measurement which is both well‐structured and sufficiently accurate ‐ a half‐way house between traditional bills and a single lump sum. By way of example, the derivation of a cost‐significant model for student hostels in Singapore is presented. Representing no more than a first step, the problems still to be resolved are outlined. Nevertheless, the techniques seem to hold much promise for the future, and others are encouraged to explore where they might most effectively be applied.

Traditional Lump Sum (TLS) methods have been the primary procurement method within Australia. Yet, their use is beginning to wane in states such as: Queensland, New South Wales and Victoria where Design and Construct, Construction Management and hybrids thereof have become the norm. Considering the demands of clients, the increasing propensity to use non‐traditional methods, the quality of drawings that are being produced, and the role of software applications such as Computer‐Aided Design in directly generating quantities, this paper seeks to examine the role Bills of Quantities (BoQs) serve and how effective they are as a pre‐contract and post‐contract tool.

Only limited empirical research has addressed the role and effectiveness of BoQs, particularly in Australia. With this in mind, the research adopted an exploratory approach to gain insights from industry practitioners about BoQs. A questionnaire survey was developed from the literature and used to solicit the opinions of practitioners about their role and effectiveness as a pre‐contract and post‐contract tool.

The distributed questionnaire survey resulted in 86 responses from industry practitioners – quantity surveyors, building contractors, and project managers. The findings fundamentally reveal that the use of Bill of Quantities prepared in accordance with the standard method of measurement is on the decline and only useful as a tool for post‐contract control.

The research has revealed that there is a need for industry to embrace alternative forms of measuring quantities in building projects. Abridged bills and builders' quantities are being increasingly demanded in Australia. Thus, it is suggested that this demand could drive the need for alternative forms of pricing in building projects and lead to the increasing use of non‐traditional methods of measurement.

The aim of the paper is to examine attitudes of general contractors operating in the Sydney region to the potential use of probability estimating and databases in cost estimating. A sample of 10 large general contractors with a turnover over $100m was selected for the study, which took place in 1993. Responses of the contractors to a standard questionnaire were obtained using face to face interviews. The research described in this paper confirmed the popularity of traditional single value estimating and highlighted the lack of use of probability cost estimating by the general contractors surveyed. The limited availability of client‐prepared bills of quantities for tendering has neither diminished their popularity among bidding contractors nor increased the use of elemental cost planning. Although databases are generally available, subjective judgements of estimators are of greater value in cost estimating. The research has concluded that a change in the estimating paradigm towards probability cost estimating, and the use of databases, are unlikely to occur in the near future.

The objectives of this paper are to discuss the constraints stemming from the unstructured nature of the cost estimation practice in Turkey and introduce a generic computer aided building cost estimation model based on a cost significant technique for Turkish construction sector public projects in its detailed design phase.

The research design was based on the simplified version of the bill of quantities method and a cost significant estimating model works on a cost database was suggested to overcome the problems. Underlying principles and basic steps of cost estimation based on cost significant work packages was explained by means of manual calculations.

In order to automate the manual building cost estimation process, the software based on cost significant work packages was developed.

The software is currently in the testing phase and is being used for educational purposes. Making use of both public sector and current market prices in the cost estimation process, increasing number of projects stored in the database for more accurate results, estimating costs of different types of projects and calculating the cost significant value factor more precisely by using statistical techniques, those being employed by global cost models are suggested for future research.

As the number of the similar projects in database is increased, the accuracy of the cost estimation is also increased.

Estimators and graduate students can use the software to estimate building cost of public housing projects in its detailed design phase.

THE need to increase the productivity of British industry is a common topic and when it is discussed the more economic use of manpower is inevitably raised. What is often lost sight of is the fact that future gains of productivity will be derived, as they were in the past, from a wider use of better machines rather than from more intensive effort by human beings. Such machines are expensive. Some of them, like the sophisticated machine tools described by the grandiose name of ‘machining centres’, are extremely costly.

Determining the duration for road construction projects represents a problem for construction professionals in Ghana. The purpose of this paper is to develop an artificial neural network (ANN) model for determining the duration for rural bituminous surfaced road projects.

Data for 22 completed bituminous surfaced road projects from the Department of Feeder Roads (rural road agency) were collected and analyzed using the principal component analysis (PCA) and ANN techniques. The data collected were final payment certificates which contained payment bill of quantities (BOQ) of work items executed for the selected completed road projects. The executed quantities in the BOQ were the total quantities of work items for site clearance, earthworks, in-situ concrete, reinforcement, formwork, gravel sub-base/base, bitumen, road line markings and furniture, length of road and actual durations for each of the completed projects. The PCA was first employed to reduce the data in order to identify a smaller number of variables (or significant quantities) that constitute 81.58 percent of the total variance of the collected data. The ANN was then used to develop the network using the identified significant quantities as input variables and the actual durations as output variables.

The coefficient of correlation (R) and determination (R²) as well as the mean absolute percentage error (MAPE) obtained show that construction professionals can use the developed ANN model for determining duration. The study shows that the best neural network is the multi-layer perceptron with a structure 3-38-1 based on a back propagation feed forward algorithm. The developed network produces good results with an MAPE of 17.56 percent or an average accuracy of 82.44 percent.

Apart from the fact that the sample size was small, the developed model does not incorporate the implications of other likely factors that may affect contract duration.

The outcome of this study is to help construction professionals to fix realistic contract duration for road construction projects before signing a contract. Such realistic contract duration would help reduce time overruns as well as the payment of liquidated and ascertained damages by contractors for late completion.

This paper proposes an alternative way of determining the duration for road construction projects using the total quantities of work items in a final payment BOQ. The approach is based on the PCA and ANN model of quantities of work items of completed road projects.

I intend in this paper to describe the methods we are evolving to deal with information problems in the building industry. But first I must say something of the industry itself. Not only is it a very large industry but it is fragmented in organization. The most common process involved in building is that the client who pays for the building initiates it by calling upon an architect to investigate his building needs in detail and to prepare designs. The architect is invariably advised by an independent quantity surveyor about likely costs, who, after approval of the designs, prepares specifications and bills of quantities. These documents, together with detailed working drawings, are used to invite tenders from general contractors. The successful general contractor enters into a contract with the client and then constructs the building. Construction is a process involving the identification and transport of large numbers and quantities of building products and their co‐ordinated assembly on site, following the instructions in the contract documents which are in the form of drawings, specifications, and bills of quantities. The building products, such as cement and blocks, and equipment such as boilers are ordered by the general contractor from manufacturers, merchants or specialist contractors to the specification of the architect. The architect is aided in design and specification by specialist technologists and consulting engineers.

The purpose of this paper is to examine the need to develop building service standard method of measurement (BSSMM) that would provide a home ground advantage and a framework for managing the cost of building services by quantity surveyors.

A review of previous research on the rules of measurement was carried out. This exercise provides the basis for questionnaire design which was administered to quantity surveyors in Malaysia construction industry.

The results indicated the need to develop BSSMM. In total, 23 variables were identified as essential features of such standard method of measurement. These variables were grouped into three categories and a priority ranking of them was carried out. The analysis revealed a strong agreement among quantity surveyors on the priority ranking of the essential features of the BSSMM.

Although, the research would assist industry stakeholders in developing BSSMM that reflects local and international best practices, there is need to further investigate how the rules of the BSSMM could be aligned with construction industry classification systems.

The availability of information and computer technology (ICT) tools has transformed the traditional practices in the industry and offered values to quantity surveyors, but if quantity surveyors’ tools cannot be consolidated and incorporated into emerging ICT applications, then QS collaboration will be difficult, and the requirements for electronic data exchange will be impractical. Therefore, this type of standard method of measurement will facilitate cross-referencing and coordination between BoQ and other documents such as drawings, specifications and tender produced by other project participants and thereby lay efficient foundation for effective collaboration of quantity surveyors in BIM model. In addition, the BSSMM will not only comply with local industry practices, it will also be internationally compatible.

Adoption of a structured format based on BSSMM to present building services cost information is essential in view of the increase in the value and complexity of building services in modern buildings. However, there is need to enhance quantity surveyors’ knowledge in the technology and cost management of building services so as to ensure the reliability of cost advice provided to clients. This goal would be partly achieved through education and training of Quantity Surveyors/Cost Consultants in the interpretation and use of the rules of an SMM.

The construction industry has particular problems in its handling of general and project documentation, arising largely from the separation of the design and construction functions, and the large number of firms involved. The Department of the Environment has issued a report proposing improvements in the total information system which suggests that classification is the key factor in any programme of work. In this paper a general account is given of the problems, the work of the DoE, the existing schemes; and proposals are put forward for the compilation of a ‘metasystem’ which would be used to control or steer the conventions used for information handling.

The purpose of this paper is to investigate the whole-life costs of non-residential green-rated building developments in Singapore to derive useful information for research and practice. When industry stakeholders like building owners, architects, engineers, quantity surveyors, builders and facility managers have detailed information about the initial and operating costs of different types of buildings, they will be able to apply whole-life costing to their existing or new projects with the intention of achieving value for money, as well as environmental sustainability. The developed index is useful to green policymakers and building owners.

Data are collected from building projects certified by the Building and Construction Authority (BCA) of Singapore under the Green Mark scheme, starting from 2005. Statistical analysis is performed on the collected data to generate the information required to build the index as well as cost database. The Paasche price index method is used to produce a weighted composite index for Singapore’s non-residential building sector.

The results show the classification of whole-life costs components by two main groups – “development and construction costs”, and “operating and maintenance costs”. There are a total of 68 cost significant items selected from 13 construction work categories. Comparing the weights for three non-residential building types, the highest is obtained for industrial building, which is followed by institutional and commercial buildings.

Without data, the description of the research has primarily dealt with the formulation of the proposed index because designing an appropriate methodology is key to ensure widespread acceptance and use.

Prospective users have to be aware that the index cannot provide information about change in absolute terms and is not very accurate as such in reflecting the actual level of costs or prices of the variable of interest. However, it is a good indicator of the relative change over time in the level of costs or prices.

It is expected that this method contributes additional information to BCA’s existing tender price index about a building’s operating costs as well since the proposed index is a measure of change in the average whole life-cycle costs of buildings over time.