Ron Wakefield

Drivers, constraints and the future of offsite manufacture in Australia

Purpose – Much has been written on offsite manufacture (OSM) in construction, particularly regarding the perceived benefits and barriers to implementation. However, very little understanding of the state of OSM in the Australian construction industry exists. A “scoping study” was recently conducted to determine the “state‐of‐the‐art” of OSM in Australia. The purpose of this paper is to report on the overall findings of the study.Design/methodology/approach – The study took a broad qualitative survey‐based approach. This involved three industry workshops, several interviews and seven case studies across four major states of Australia. The study surveyed a range of suppliers across the construction supply‐chain, incorporating the civil, commercial and housing segments of the market.Findings – The study revealed that skills shortages and lack of adequate OSM knowledge are generally the greatest issues facing OSM in Australia. OSM uptake into the future is dependent on many factors, not least of which is a be...

Concrete prefabricated housing via advances in systems technologies: Development of a technology roadmap

Purpose – The purpose of this paper is to discuss the roadmapping methodology and its application to concrete prefabricated housing in Australia.Design/methodology/approach – The paper describes the concrete and housing industries of Australia collaboration in a project to develop a technology and innovation roadmap that will advance the concrete industrys supply chain capabilities by identifying and mapping innovation necessary for prefabricated concrete house construction. The roadmap lays out what is necessary for an off‐site systems‐based approach to housing construction in Australia. The systems‐based approach to prefabricated concrete products is a relatively new and developing extension of the concrete industry supply chain in Australia. New manufacturing technologies and innovations, which are emerging locally and from overseas, make these potential extensions possible. For the long‐term sustainability of the concrete industry, it is critical that it better understands how to adopt cooperative in...

Analysis of Disruptions Caused by Construction Field Rework on Productivity in Residential Projects

Operational performance in residential construction production systems is assessed based on measures such as average house-completion time, number of houses under construction, lead time, and customer service. These systems, however, are prone to nonuniformity and interruptions caused by a wide range of variables such as inclement weather conditions, accidents at worksites, fluctuations in demand for houses, and rework. The availability and capacity of resources therefore are not the sole measures for evaluating construction production systems capacity, especially when rework is involved. The writers’ aim is to investigate the effects of rework timeframe and frequency/length on tangible performance measures. Different call-back timeframes for rework and their impact on house-completion times are modeled and analyzed. Volume home-building was chosen as the industry sector studied in the research reported in this paper because it is a data-rich environment. The writers designed several experiments to model on time, late, and early call-back timeframes in the presence of rework with different length and frequency. Both mathematical modeling and discrete-event simulation were then used to compare and contrast outputs. The measurements showed that the average completion time is shorter in systems interrupted by frequent but short rework. In other words, a smaller downstream buffer between processes is required to avoid work starvation than those systems affected by infrequent but long interruptions. Early call-backs for rework can significantly increase the number of house completions over the long run. This indicates that there is an opportunity for the mass house-building sector to improve work practice and project delivery by effectively managing rework and its related variables. The research reported in this paper builds on the current body-of-knowledge by applying even-flow production theory to the analysis of rework in the residential construction sector, with the intention of ensuring minimal disruption to construction production process and improving productivity.

Prevention through design: Trade‐offs in reducing occupational health and safety risk for the construction and operation of a facility

Purpose – The research aims to explore the interaction between design decisions that reduce occupational health and safety (OHS) risk in the operation stage of a facilitys life cycle and the OHS experiences of workers in the construction stage.Design/methodology/approach – Data was collected from three construction projects in Australia. Design decisions were examined to understand the reasons they were made and the impact that they had on OHS in the construction and operation stages.Findings – The case examples reveal that design decisions made to reduce OHS risk during the operation of a facility can introduce new hazards in the construction stage. These decisions are often influenced by stakeholders external to the project itself.Research limitations/implications – The results provide preliminary evidence of challenges inherent in designing for OHS across the lifecycle of a facility. Further research is needed to identify and evaluate methods by which risk reduction across all stages of a facilitys l...

The development and testing of a hierarchical measure of project OHS performance

Purpose – This paper seeks to examine a hierarchical measurement model for occupational health and safety (OHS) performance developed for use in the Australian construction industry and tested over the life of one case study construction project. The model was intended to provide a more sensitive and informative measure of project OHS performance than traditional injury frequency rates.Design/methodology/approach – Two measurement tools were tested. The tools, a monthly weighted safety index and a quarterly safety climate survey, were used to measure OHS performance and performance data are presented.Findings – The data suggest convergent validity, indicated by consistent results between the two measures. Results also indicated that a combination of measurement techniques provides more comprehensive data pertaining to project OHS performance and enables the diagnosis of OHS issues that would be undetected with reliance exclusively on traditional measures, such as lost time injury frequency rates.Research ...

Work-Health and Safety-Risk Perceptions of Construction-Industry Stakeholders Using Photograph-Based Q Methodology

AbstractWork health and safety (WHS) on construction sites can be influenced by decisions made upstream from the construction stage. The effectiveness of WHS risk management relies on decision makers’ ability to decide appropriate strategies to mitigate/control risks. However, it is unclear whether upstream decision makers share similar WHS risk perceptions with those who undertake the construction work. This study used Q methodology to explore WHS risk perceptions of architects, engineers, construction managers, and WHS professionals. Photographs depicting different technologies/methods were used to capture professionals’ WHS risk judgments. Data were analyzed to identify the within-group and between-group similarity/difference in professionals’ WHS risk perceptions. The data-analysis result indicates the coexistence of within-group difference and similarity, as well as between-group difference and similarity in WHS risk perceptions. The research contributes to the body of knowledge by showing that WHS r...

Exploring the link between early constructor involvement in project decision-making and the efficacy of health and safety risk control

The position of the constructor in communication networks, including those before the commencement of construction, is likely related to the quality of work health and safety (WHS) outcomes realized. In order to examine the extent of this relationship, 23 cases were drawn from 10 participating construction projects in Australia and New Zealand. Social network analysis was used to mathematically and graphically model information exchanges in 13 of these cases. For each case, the quality of WHS risk control outcomes was measured. This measurement was based on an established ‘hierarchy of control’ in which risk controls are classified in descending order of effectiveness from the elimination of a hazard (the most effective) to the reliance on personal protective equipment (the least effective). Social network metrics were calculated reflecting: (1) the ratio of actual links among parties in the project network relative to the maximum number of links possible (network density); and (2) the extent to which the constructor communicated with other parties in pre-project planning and design stages (the constructors’ degree centrality). Network metrics were compared for cases in which the risk control scores were higher and lower than average. The results showed a significant difference in constructors’ pre-construction degree centrality for cases with high and low risk control scores. The results provide preliminary evidence as to the potential WHS benefits of ensuring that constructors’ knowledge about construction methods, materials, WHS risks and means of risk control, are integrated into pre-construction decision-making.

Quantitative analysis of rate-driven and due date-driven construction: production efficiency, supervision, and controllability in residential projects

AbstractConcerns about production efficiency, quality, and affordability in the residential construction indicate there may be benefits in adopting alternative production control strategies to those traditionally used. Reducing adverse effects of exogenous variability in demand and endogenous variability in process are the ultimate goals of production control strategies. For residential construction this means controlling the number of houses under construction and controlling the start rate of new house constructions. The aim of this investigation is to compare and contrast the outcomes of these two production management strategies. Production data of two volume house builders in Victoria and Queensland, Australia, were collected. Tangible performance metrics from the builders were analyzed and compared using the principles of queuing theory. Then numerous simulation experiments were designed and run to analyze different what-if scenarios in the building environment. A special purpose simulation template...

An investigation of property-related decision practice of Australian fund managers

Purpose – In Australia, the A

Designing a game for occupational health and safety in the construction industry

2.2 trillion managed funds industry including the large pension funds (known locally as superannuation funds) are the dominant institutional property investors. While statistical information on the level of Australian managed fund investments in property assets is widely available, comprehensive practical evidence on property asset allocation decision-making process is underdeveloped. The purpose of this research is to identify Australian fund managers property asset allocation strategies and decision-making frameworks at strategic level. Design/methodology/approach – The research was undertaken in May-August 2011 using an in-depth semi-structured questionnaire administered by mail. The survey was targeted at 130 leading managed funds and asset consultants within Australia. Findings – The evaluation of the 79 survey respondents indicated that Australian fund managers property allocation decision-making process is an interactive, sequential and continuous process involving m...