Contractor Monitoring of Productivity and Sustainability in Building Refurbishment
The aging building stock in Europe and regulatory requirements to decrease energy consumption make sustainable refurbishment a valuable alternative to other construction activities. The construction industry appears to suffer from low productivity growth, and the construction productivity debate concludes that productivity measurement is difficult, not least due to changes in input and output qualities. Building certification schemes are one way to measure sustainability. However, existing schemes focus mainly on environmental sustainability and new construction, while refurbishment differs from new construction. The purpose of this research is to analyse the relation between the theoretical concepts of sustainability and productivity in the context of measurement, and to investigate the performance measures used in housing and office refurbishment projects.
This thesis is based mainly on literature reviews in the areas of sustainability, productivity, performance measurement and building refurbishment. The empirical data were collected through eight semi-structured interviews - five with site managers employed by large contractors, and three with general or site managers from small and medium sized enterprises (SMEs). All the interviewees were involved in housing refurbishment projects.
The findings of this thesis suggest that current methods of measuring productivity in the construction industry are unsatisfactory. Simple area-based methods and measurement of labour productivity do not capture changes in input and output qualities. Most existing building certification schemes have not taken account of the overall sustainability of the refurbishment process. They reflect the fundamentals of sustainability very poorly, and they tend to hide conflicts between sustainability and productivity. They mostly lack a clear refurbishment focus, even in schemes that are supposed to include refurbishment. Lack of time is a frequent excuse for not measuring productivity on sites, although perceived time pressure might be a symptom of complex resource allocation. SMEs pay little attention to sustainability measurement because they do not see it providing economic benefits, while large contractors invoke lack of client demand.