Actual service life prediction of building components

In recent years, sustainability and life cycle cost in the construction industry have been given great attention in many countries due to the heavy climatic and environmental impact from this sector. In Denmark, a sustainability certification scheme for buildings has been developed including a condensed method for assessment of life cycle costs for buildings. Estimation of life cycle costs has traditionally been based on predicted service life for building components in terms of technical performance. This paper suggests a method for taking into account other contributing factors such as economics, aesthetics and use of the building. Each of these factors is regarded as a stochastic variable and can be seen as competing causes of bringing service life to an end. A model is proposed for combining such variables resulting in the actual service life of building components. Furthermore, the paper presents an analysis of service life of buildings as such with respect to the use of the building partially based on analysis of data from the nationwide Danish register of buildings and housing as well as turnover in the Danish construction industry from refurbishment and demolition activities. Finally, it is discussed how to adjust the model for practical purposes, and a scheme for actual service life for selected building components important for analysis of sustainability is linked. The schemes are now being implemented as basis for sustainability certification of new buildings in Denmark.