Energy saving and airtightness of blocks of flats in Lithuania.

Measurements of the airtightness of blocks of flats in Lithuania were carried out between 1995 and 1997 to assess the effectiveness of energy saving measures. At that time there was no real data on the airtightness of such dwellings available. The aim of the measurements was to evaluate how much heat could be saved by diminishing the air change rate. Since there are no thermostats installed in the dwellings, 'tightening' becomes the only measure available to increase indoor temperature. Unfortunately, the results show that the popular expectation that energy was being wasted are not well grounded. We conclude that there is no real possibility for saving heat in small dwellings without contravention of health requirements except in isolated cases. The mean air change rate was found to be approximately 1.5 h-1 and further steps to tighten the building envelopes could only save energy in some large dwellings of three and more rooms.