This paper describes the development of a model which can be used to explore the technical feasibility and policy implications of attempting to achieve 60 - 90% reductions in the C02 emissions from the UK housing stock by the middle of the next century. Reductions of this order are likely to be required across the industrialised countries in order to stabilise the atmospheric C02 concentration and global climate. In order to be able to investigate this problem, a highly disaggregated physically based energy and carbon dioxide model of the UK housing stock has been developed.