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The aim of this paper is to establish the extent to which quantity surveyors undertake cost planning and the manner in which elemental cost estimating is currently applied. Elemental cost analysis is perhaps the best known product‐based cost model and provides the data upon which elemental cost planning is based. The technique has been used by quantity surveyors to base their predictions during the design stage since the 1950s. There has, however, been no recent attempt to establish the extent to which practicing quantity surveyors use this technique (if indeed they still do so) and the manner in which cost analysis is currently carried out.

A nationwide questionnaire survey of UK quantity surveying practices was undertaken. The survey sought to establish: the extent to which elemental cost estimates are prepared for proposed developments; the format used to prepare these estimates (together with the degree to which the BCIS Standard Form of Cost Analysis (SFCA) is still used); the factors that affect the use of elemental cost estimates; and the level of the detail to which these estimates are analysed. Further, the survey investigated the predilection within the surveying profession for single‐figure and elemental format cost models.

The study clearly establishes that UK quantity surveying practices routinely undertake elemental cost planning during the design phase of a project and that the BCIS SFCA is the most popular approach to cost planning. Further, it establishes that while around 70 per cent of the respondents would not currently use single figure estimating software, between 85 and 95 per cent indicated that they would be encouraged to use it if it was able to generate an elemental breakdown of its prediction.

The paper offers insights into the current use of cost planning and analysis methods in the UK.

The aim of this study is to investigate the reasons for disparity between design stage elemental cost plan and final tender sum (contract sum) in building procurement. A number of risk factors responsible for such variation were identified through case study projects from which data were extracted.

Literature review determined the risk factors inherent in the preparation of design stage elemental cost plan. Interviews and thematic analysis identified the risk factors responsible for the disparity between design stage elemental cost plans and final tender sums. Analysis of documents obtained from the archives of study participants (consultant quantity surveyors) complemented responses from the interviews.

The review revealed a number of inherent risks in the design stage elemental cost plan development. The interviews further indicated that risks have an impact on and are responsible for the deviations experienced. The assessment of these risk elements could assist in determining the final tender sum from cost plans.

Findings revealed disparity between elemental cost plans and final tender sums in the region of −14 and +16 per cent. The risk factors identified were responsible for the deviations observed. With this information, Quantity Surveyors are more able to accurately forecast final tender sums of building projects from cost plans through proper risk identification and analysis, thus increasing the accuracy of design stage elemental costing.

To the best of the knowledge of the researchers, there is no recent documentary evidence of an investigation into the reasons for disparity between design stage elemental cost plan and final tender sum in traditional building procurement in New Zealand construction.

Refurbishment is inherently more sustainable than building new. However, planned and actual costs of refurbishment projects are bound to vary due to the complex nature of most such projects. This can affect the performance of refurbishment work. The purpose of this paper is to examine factors responsible for elemental cost variations between the actual and planned costs of refurbishment projects. The study also examines factors that contribute to differences in actual and planned cost between refurbishment and new build projects.

A quantitative approach was adopted for this study. A literature review identified factors responsible for elemental cost variations in refurbishment projects, as well as factors responsible for differences in actual and planned cost of new build and refurbishment projects. This was followed by a questionnaire survey of refurbishment projects across Malaysia. A total of 55 respondents provided input through a questionnaire survey to identify these factors.

This study demonstrates that procurement strategy (PS), inappropriate contractors (IC), poor project management (PPM), availability of funding, materials and equipment, and force majeure (FM) significantly affect refurbishment cost performance. Electrical installations, firefighting equipment, and painting were the building elements most affected by cost variations. A regression model for refurbishment cost prediction indicates that PS, IC, PPM, availability of funding, materials and equipment, and FM were significant predictors of building refurbishment cost performance.

This paper provides insight into the major factors affecting elemental cost variation of refurbishment works, as well as building elements most affected by cost variations and provides a model for predicting refurbishment cost performance.

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.

There has been a lack of research, particularly within the New Zealand (NZ) context, focusing on the identification and assessment of risk factors for construction projects, leading to a wide variation between design-phase elemental cost plans (ECPs) and the outturn tender sums (OTS). Still to be investigated is how risks interact to produce such variability. This study aims to determine the risk-influencing factors, identified through risk measurement, during design development.

This study adopted literature review and online questionnaire survey. The literature review was used to identify the factors affecting project budgetary performance, which was used to design the questionnaire survey culminating in data analysis. The questionnaire was administered to 64 practising project managers (PMs) in NZ. Their responses were analysed using descriptive statistics, mean ranking analysis, degree-of-risk measure and correlational analysis, to find the top-five risk factors impacting the variability observed, through ranking the mean and degree of risk values that produce such variability.

Significant risk factors were identified from the questionnaire survey analysis, such as changes in project owner/stakeholder requirements, experience of project team, site condition information, competency of consultants and information flow and quality. These provided some insights in explaining the variability between the design-phase ECPs and OTS based on risk impacts from PMs’ viewpoints.

Findings revealed a drift of 23.86% in budgeted costs (inflated risks), which seems significant. Prioritising top risk factors may provide handy information for researchers on the variables that could be relied upon for the development of a forecasting model for application in NZ.

The study findings have implications for PMs seeking to provide information on mitigation strategies by using risk management approach, considering the influence of development risks on building project delivery and, consequently the project owner’s financial position. To guard against wide variation between design-phase ECPs and OTS, the main contribution of this study is to raise consultants’ awareness of the important risk factors for their planning at the outset, thus assisting PMs in pro-actively managing their clients' budgets.

This study creates value by synthesising literature on construction project budgeting and highlighting areas for further research. By giving adequate attention to key risks associated with budget overruns in commercial projects, variability between ECPs and OTS, a common phenomenon in NZ, can be controlled to achieve cost savings. Based on this, further study suggests the development of a model that could assist the stakeholders in NZ to more reliably predict OTS from the design-phase ECP and pro-actively avoid unfortunate budget/cost overruns, disputes and even project abandonment.

The purpose of this paper is to elicit the activities in geometric 3D computer-aided design (CAD) estimating. Construction estimators usually target the structural integrity of data underlying project designs while measuring quantities and developing estimates. However, there are different ways to this. There is considerable evidence to suggest substantial distinction between data structuring in geometric and parametric CAD (building information modelling). Each of these platforms also appeals to estimators in the various practice domains differently. Regardless, the developments in the use of geometric and parametric CAD for design and management purposes have been rapid.

The study focuses on the various perspectives within the different construction business domains. Interviews, focus group discussions and direct observation methods were used to explore data on estimating activities in 3D CAD from two public organizations, two large contracting firms, two quantity surveying consulting practices, two specialist-project companies and four software development and vending firms. These involved 17 middle-top management estimators who have had extensive experience in the industry. As the activities were elicited, participants were able to ascribe relative importance to each of the activities, and these were logically compared across the different practice domains.

Thirty-one activities were identified as the components of estimators’ procedures leading to reliable outcomes in estimating 3D CAD designs. Logical correlations were discussed through extant literature towards forming a centroid model which could be used for numerous industry applications, including software development, knowledge transfer between organizations, employees’ hands-on training, curriculum design for academic institutions and as a policy framework for professional institutions on estimating practice. Further areas of research were also highlighted.

This work is an original piece. It is neither published nor under consideration elsewhere.

Building cost planning was originally developed in the framework of traditional procurement methods with conventional documentation, tendering and administration processes. With the advent of alternative forms of procurement with more fluid approaches to design stages and documentation, the need for sound cost planning does not appear to diminish. As a process established on solid theoretical foundations, cost planning should be robust enough to adapt and flourish in a variety of procurement environments. However, little documentation and analysis of transformed and adapted forms of cost planning appear to have been made. This case study of a design‐construct company in Melbourne, Australia, presents and explores a contemporary form of building cost planning integrated into a design cost management approach adopted by a construction company experienced in alternative forms of procurement. The article traces this process on a design‐construct project from inception to the end of the design development stage and tender. Whilst the fundamental framework of cost planning remains intact, the focus and detail in each of the stages are guided by the company's priority for greater financial control over the cost and value implications of design and other decisions. This recently established working model of design cost management in this company has been designed to deliver added value to the client through a better balance of time, cost and quality in each project.

Provides an overview on the development of information production in construction. It is suggested that there is a need for the professional organisations to re‐think the way they produce project information so that the opacity in current project information is replaced by transparency so that all the stakeholders in the procurement process can move from their adversarial/bargaining positions to one that encourages a team problem‐solving approach.

This research aims to develop conceptual phase building project cost forecasting models by exploring the relationship of existing plan shape complexity indices and general design morphology parameters with total construction cost.

Plan shape indices proposed to date by the literature for measuring building design complexity are critically reviewed. Building morphology is also dictated by town planning restrictions such as plot coverage ratio or number of storeys. This study analyses historical data collected from 49 residential building projects to develop multiple linear regression (MLR) and artificial neural network (ANN) models for forecasting construction cost. Existing plan shape coefficients are calculated to evaluate the geometrical complexity of sampled projects. Ten regression-based cost estimating equations are totally derived from stepwise backward and forward methods, and their predictive accuracy is contrasted: to performance levels reported in past studies and to ANN models developed in this research with multilayer perceptron architecture.

Analysis of plan shape indices revealed that 85.7% of examined past projects possess a high degree of design complexity, hence resulting in expensive initial decisions. This highlights the need for more effective early design stage decision-making by developing new building economic tools. The most accurate regression model, with a mean absolute percentage error (MAPE) of 19.2%, predicts the log of total cost from wall to floor index and total building envelope surface. Other explanatory variables resulting in MAPE values in the order of 20%–22% are total volume, volume above ground level, gross floor area below ground level, gross floor area per storey and total number of storeys. The overall MAPE of regression-based equations is 24.3% whilst ANN models are slightly more accurate with MAPE scores of 21.8% and 21.6% for one hidden and two hidden layers, respectively. The most accurate forecasting model in the research is the ANN with two hidden layers and the sigmoid activation function which predicts total building cost from total building volume (19.1%).

This paper introduces MLR-based and ANN-based conceptual construction cost forecasting models which are founded solely on building morphology design parameters and compare favourably with previous studies with an average predictive accuracy less than 25%. This paper is expected to be beneficial to both practitioners and academics in the built environment towards more effective cost planning of building projects. The methodology suggested can further be implemented in other countries provided that accurate and relevant data from historical projects are used.

Kaizen in construction is a new paradigm stemming out of lean production systems. Construction companies in developing economies, such as Nigeria, have a task to innovate to liquidate in certain cases. With the aid of kaizen, which encompasses the benefit of stakeholder relationship improvement and management, profitability enhancement and delivery of projects to satisfied clients, construction companies can realise expected growth. An exploration of the critical success factors (CSF) and associated drivers within the limits of the scope is essential. The paper aims to discuss these issues.

Exploratory factor analysis statistical tests categorised the CSF identified in the literature review section. A detailed sampling approach extracted 135 questionnaires under the five-point Likert scale format from a larger population in Nigeria. An exploration of important drivers and iteration of eigenvalues combined with asymptotic significance of the drivers provided the CSF and significant drivers.

Construction management function, operational efficiency, construction business ethics and construction cost management were the CSF established from the exploratory factor analysis tests. It was confirmed that kaizen can be adopted in Nigerian construction companies with reflections on the principal drivers for the CSF.

The exploration of the CSF and drivers associated with kaizen implementation can be applied to other developing countries with considerations of implementation in terms of cost and time.

The identification of CSF provides ample opportunity for consideration of kaizen in construction companies. The findings of this study are a basis for investigations into cost and time implications of kaizen adoption in construction companies.