Housing is a readily available setting for a number of public health interventions, but there is a lack of research results from intervention studies alone to support improved housing as a robust means to improve health. Insulating existing homes, providing effective safe heaters, and where necessary subsidized power, has been shown theoretically and in practice, to increase older peoples health and wellbeing and the health of children with asthma. In some cases the intervention prevented only further deterioration in health. The construction of new passive houses that are well insulated, have no active heating or cooling systems and use passive solar energy even in winter time, costs around 10% more but reduces energy running costs by a factor of 10 over the building lifetime. Such sustainable housing can increase the disposable income of the households and help to reduce inequalities.