The factor X in dwellings: the construction of an indicator by combining life cycle assessment with the indoor climate
05 / 2000 - 12 / 2006
In the housing sector, the question has arisen with which amount the environmental load of buildings can be decreased. This is a part of the factor X debate, in which the possible reduction of the environmental loads is discussed. One of the methods to assess the environmental load of buildings is through using the life cycle assessment methodology. However, this methodology needs to be improved and extended. For example, the indoor environment is not taken into account yet and the weighing and aggregation of the different effects should be improved. Aim: The aim of this research is the improvement of the current LCA methodology for dwellings by extending it with the indoor environment and improving the weighing and aggregation methodology. Furthermore, the highest factor X that is achievable at this moment for dwellings will be calculated. Research: The first part of this research consists of the development of a model, with which the indoor environment of a dwelling can be assessed. The impacts of components like volatile organic compounds, radon and particulate matter, noise and odour on the human health will be evaluated. The human health damage is calculated using the disability adjusted lost years (DALY) approach. In this approach, the years living disabled and the years of life lost due to a premature death are weighed and summed. This proves to be a better yardstick than the current scoring methods for toxicological risks to humans. Next, the methodology of weighing and aggregating of the different effects on the human health will be evaluated and improved when necessary. In addition, the uncertainties will be mapped. Finally, sets of measures that are feasible for a building that is going to be built and an existing building that is to be renovated are developed. For these sets, an environmental indicator (reflecting the factor X) will be determined with the new method of life cycle assessment. In this way, the maximum achievable value of factor X can be determined with a maximum practicable effort to improve buildings environmentally.