Indoor radon and air quality investigations in new or renovated energy-efficient swiss single-family dwellings

The perspectives of a new energy crisis subsequent to the depletion of natural resources along with the increase of energy costs make, more than forty years after the first oil crisis, energy savings a priority. This lead to rethink building practices so as to make it more sustainable and economical in terms of energy consumption by ensuring the air tightness and a good thermal insulation. Indeed, the less we ventilate such sealed houses, the more moisture, number and level of pollutants increase in the indoor environment. The deterioration of the indoor air quality and the appearance of occupants non-specific health disorders are the consequences. Preliminary results indicate the attention to pay to energy-efficient buildings. On the one hand, the concentration of indoor radon has a clear tendency to increase after an energy saving action. On the other hand, it appears that even though the new Swiss energy efficient houses seem less affected by this problem than the traditional renovated houses, or even transformed according to these label requirements, unexpected situations may still arise. People living in energy saving buildings need to be well informed about the risks and about “what-to-do and not-to-do” living in such “high tech” houses. Maintenance of technical installation can also be troublesome