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The purpose of this paper is to quantify fitout churn in office buildings to more accurately evaluate the recurrent embodied energy in life cycle assessment studies.

Three research methods were used in the context of Central Business District (CBD) office buildings in Sydney. Method 1 involved leasing records from 528 office buildings; method 2, a leasing history from a selective sample of three prime grade office buildings; method 3, a targeted survey of 21 property professionals concerning fitout churn cycle estimates.

Prime buildings are the area of most interest to fitout churn because they represent a large proportion of total office floor area. The churn rate differs according to office tenancy type (as defined by small, medium and large leased areas). Large tenants occupy the majority of floor space. Lease duration as obtained from Method 1, offers a reasonable proxy for predicting fitout churn. Using this method coupled with weighted-average calculations, the data indicate a fitout churn rate of 8.2 years.

Variability concerning the situational context of Sydney CBD office buildings restricts broad generalisability of the findings. However, the research method used in this study would enable broad-based comparison and the potential for verification.

The main contribution of the research is to improve the ability to accurately predict fitout churn cycles as previous work only involves limited case studies and arbitrary estimates, thus lacking a strong evidence based.

The short life cycle replacement of fitout in modern high-rise office buildings represents an under-researched waste problem. This paper aims to quantify the amount of demolition waste from office strip-out including attention to waste streams going to landfill, reuse and recycling.

Quantitative waste data (by weight) were measured from 23 office fitout projects situated in “A” grade office building stock from the Sydney CBD. Waste streams were measured separately for landfill, reuse and recycled materials. Descriptive and clustering statistics are presented and analysed.

From a total of 9,167 tonnes office fitouts demolished, 5,042 tonnes are going to landfill. The main contributor to landfill stream is the mixed waste generated in a fast-track demolition process. This approach partly resulted from the office interiors lacking regularity and easy disassembly. Moreover, considerable variability is observed in the waste per area, the waste streams and the waste compositions. Also, it is noteworthy that the recycled waste stream considerably increases when there exist economically viable conversion facilities, as for metals, hard fills and plasterboards.

The research is focused upon work practices that take place in Australia; therefore, generalisability is limited to situations that have similar characteristics. Future studies are needed to verify and extend the findings of this research.

A key area arising from the research findings is the need to design fitout with recycling and reuse in mind to divert more from landfill. This must explore and incorporate onsite demolition processes to ensure the design is well suited to commercially dominant processes in the overall demolition process, as well as attention to developing economies of scale and viability in re-sale markets for reused items.

Little empirical or quantitative research exists in the area of office fitout waste. This research provides entry to this area via quantifiable data that enables comparison, benchmarking and diagnostic ability that can be used to underpin strategic solutions and measurement of improvements.

Measuring onsite productivity has been a substance of debate in the construction industry, mainly due to concerns about accuracy, repeatability and unbiasedness. Such characteristics are central to demonstrate construction speed that can be achieved through adopting new prefabricated systems. Existing productivity measurement methods, however, cannot cost-effectively provide solid and replicable evidence of prefabrication benefits. This research proposes a low-cost automated method for measuring onsite installation productivity of prefabricated systems.

Firstly, the captured ultra-wide footages are undistorted by extracting the curvature contours and performing a developed meta-heuristic algorithm to straighten these contours. Then a preprocessing algorithm is developed that could automatically detect and remove the noises caused by vibrations and movements. Because this study aims to accurately measure the productivity the noise free images are double checked in a specific time window to make sure that even a tiny error, which have not been detected in the previous steps, will not been amplified through the process. In the next step, the existing side view provided by the camera is converted to a top view by using a spatial transformation method. Finally, the processed images are compared with the site drawings in order to detect the construction process over time and report the measured productivity.

The developed algorithms perform nearly real-time productivity computations through exact matching of actual installation process and digital design layout. The accuracy and noninterpretive use of the proposed method is demonstrated in construction of a multistorey cross-laminated timber building.

This study uses footages of an already installed surveillance camera where the camera's features are unknown and then image processing algorithms are deployed to retrieve accurate installation quantities and cycle times. The algorithms are almost generalized and versatile to be adjusted to measure installation productivity of other prefabricated building systems.

Building Information Modelling (BIM) is becoming the new norm in the AEC industry and also part of many construction project management (CPM) programmes. The purpose of this paper is to address the difficulty and challenges in walking the narrow line between an industry-ready BIM and a BIM that is good for student learning and offers a realistic and practical, but simultaneously achievable, learning environment.

An action research was conducted in an undergraduate CPM education setting.

Key challenges encountered were availability of appropriate teaching and learning resources for BIM; finding the balance between theory and practice, technology and process, and traditional and emerging CPM methods; and facilitating staff’s professional development. Closer look was given to the teaching and learning resources for BIM. Theoretical resources that are available for education in the form of books, articles and websites are easy and straightforward to locate. Likewise, a good share of various tools are available for educational purposes. On the other hand, actual building models represent a challenge in terms of preparing and optimising usage of the model for high-quality educational purposes. Several different approaches for obtaining BIM resources were identified with various challenges and benefits.

The results and recommendations will assist educators to better understand and overcome the practical challenges related to BIM education, especially those related to teaching and learning resources.

A problematic issue for new approaches to prefabricated timber construction is simply that there is insufficient productivity measurement data to assist estimation of resource usage, speed onsite and best practice. A lack of information potentially results in increased pricing behaviour which may slow the uptake of prefabricated construction. The purpose of this paper is to measure installation productivity onsite for prefabricated timber floor cassette panels and develop sufficient understanding of the process to suggest improved practices.

A time and motion approach, paired with time-lapse photography was used for detailed capture of prefabricated cassette flooring installation processes onsite. An emphasis was placed on work flow around crane cycles from three case study projects. Time and date stamping from 300 crane cycles was used to generate quantitative data and enable statistical analysis.

The authors show that crane cycle speed is correlated to productivity including gross and net crane time scenarios. The latter is refined further to differentiate uncontrolled outlying crane cycles from normally distributed data, representing a controlled work process. The results show that the installation productivity rates are between 69.38 and 123.49 m²/crane-hour, based on normally distributed crane cycle times. These rates were 10.8–26.1 per cent higher than the data set inclusive of outlier cycles. Large cassettes also proved to be more productive to place than small.

The contribution of this research is the focus on cranage as the lead resource and the key unit of measure driving installation productivity (in cassette flooring prefabricated construction), as distinct from past research that focuses on labour and craft-based studies. It provides a different perspective around mechanisation, for resourcing and planning of work flow. Crane cycles provide a relatively easy yet reliably repeatable means for predicting productivity. The time-lapse photographic analysis offers a high degree of detail, accuracy and objectivity not apparent in other productivity studies which serves to enable quantitative benchmarking with other projects.

The impact of service quality on customer satisfaction during detached housing construction in Australia is investigated for a targeted customer – one whose expectations focus on “price and product” and not “service quality”. The purpose of this paper is to see if service quality impacts on customer satisfaction during construction, despite the apparent conflict in expectations.

A detailed single case study methodology is used, focusing on the aforementioned customer as the unit of measure. A longitudinal design is employed by measuring customer satisfaction and service quality “gap scores” at four stages during construction, using a survey instrument adapted from the consumer research literature. This is coupled with qualitative interview data coded into a linked set of definable service incidents.

The study finds that irrespective of having price and product oriented pre-purchase expectations, customer satisfaction is closely related to perceptions of service quality during onsite construction. This only occurs for a selective set of “active” service quality dimensions – especially responsiveness and reliability dimensions. These dimensions appear to be driven by the customer’s underlying level of exposure to both positive and negative service incidents, and the ratio between the two appears to direct the strength and direction of “gap scores”. Once the physical end product materialises, the customer gradually focuses more on the objectivity and realisation this offers, and less on service quality.

The paper facilitates theory development in terms of generating testable variables effecting the dynamic relationship between service quality and customer satisfaction, during construction. The approach enables an increased ability to identify and explain how contextual variables, linked to specific customer types, impact on the relationship. The generalisability and validity of the findings are discussed.

The study aims to assist contractors in strategically managing customer satisfaction by applying marketing theory to housing construction. It specifically aims to investigate service quality as an input to pre‐purchase (pre‐contract) expectations in the made‐to‐order housing construction market.

A theoretical model is developed from the literature concerning the formulation of expectations during the pre‐purchase decision process. Data from 51 detailed telephone interviews with customers undertaking live housing projects are analysed using both thematic analysis and qualitative comparative analysis.

A revised model is provided, which includes a dimensionalised set of traits to suit housing construction customers. Strings of traits are then used to develop holistic customer profiles, including situations where service quality is fully present in critical pre‐purchase expectations and where it is totally absent (i.e. price and product design dominate instead).

The model and profiling technique offer a generalisable basis for contractors and others involved in housing delivery to better understand customer expectations, thus making it possible to better manage customer satisfaction.

The research contributes to new knowledge by providing a systematic means of understanding customer behaviour at a depth that is not apparent in the current body of literature. Theory is also developed in a way that has practical application, i.e. customer profiles can be used to assist daily marketing and management operations.

The purpose of this paper is to quantify and profile the indicative amount of retrofits in office buildings as a necessary step in quantifying the recurring embodied energy in office buildings. Buildings are a major source of energy usage and emissions, and office buildings are a significant contributor to this situation. Life cycle assessments in this area have tended to neglect the potentially large impact arising from recurring embodied energy associated with office fit-out – which is often akin to a short-term consumable rather than a long-term durable in many multi-storey buildings.

This study used building permit data from the Melbourne Central Business District (n = 986) over the period 2006-2010 (inclusive) to quantify the number of retrofits and related trends. Building on this, a small number of targeted case study buildings were used to probe specific issues in profiling trends associated with high-frequency trends arising from the main sample.

The data show that the number of retrofits varies according to location, grade, size and the age of buildings. Using the case study data, there is initial evidence to suggest that between 46 and 70 per cent of the floors in a high-rise office building will undergo retrofit in a five-year period. Further research should apply these data to recurring energy modelling for office buildings.

One limitation which applies to this study is that the research is limited to a defined geographical area in one Australian city, Melbourne. Secondly the study covers a specific period, and the number of retrofits may be affected negatively or positively depending on the prevailing market conditions.

This paper raises important questions in respect of life cycle carbon emissions in the context of prevailing trends to shorter lease terms and practices around fit-out.

The retrofit of office buildings tends to go unnoticed and unmeasured in the debate about sustainable buildings. The paper provides original thought development and important measurement input which will assist in providing a more accurate and meaningful life cycle assessment of office buildings.

This paper aims to develop a theoretical model concerning the way service quality impacts on the perceptions of customers in housing construction.

The model is based on marketing theory merged with construction concepts. The Australian housing industry is used as a basis for creating a generalised market scenario. Parasuraman et al.'s “gap model” is adapted to suit the design and construction process by merging it with elements of Winch et al.'s model of service quality in construction projects.

The model arising from the research shows a structured and contextualised view of how service quality theoretically occurs in housing construction. It differs from previous models in so far as recognising that customers make service quality judgements progressively during the design and construction process, rather than waiting for the end product to emerge. Such judgements may influence the direction and dynamics of the project.

The paper fosters interdisciplinary research and the resulting model has the potential to facilitate the development of customer profiles so that housing contractors can improve management techniques and use service quality as a means of seeking competitive advantage in the market place.

To develop a method for measuring consumer‐perceived tolerances concerning the appearance of unitised construction finishes (e.g. tiling, brickwork, paving, jointed façades).

Consumer perceptions were converted into physical tolerances by drawing on an area of the behavioural sciences known as psychophysics. In particular, Weber's Law was used, which applies a formulaic approach to creating perception‐based constants. A trial of this approach was undertaken on floor tiling in 50 residential properties. Tiling was chosen because it was considered representative of situations where the appearance of the finished work was important to consumer perceptions. In particular, consistency of tile joint width was measured, which had the advantage of tapping into tiles laid askew, in poor alignment or affected by variable tile sizes.

Weber's Law offers an appropriate means of objectifying consumer perceptions into physically measurable tolerances. It was found that joint width in tiling can vary up to 70 per cent before consumers find the work beyond their threshold of acceptance – causing them to think the work “ugly”. Saturation of such joints can occur up to three times per 5m² area without causing consumers to complain.

Such an approach can be easily applied to any unitised construction element where the regularity of appearance is important.

The study provides a new and more balanced approach to the assessment of construction quality by ensuring THAT consumer expectations are taken into account, as well as the normal emphasis on technical quality standards.