INDOOR CLIMATE CONDITIONS IN LIGHTWEIGHT DETACHED HOUSES IN COLD CLIMATE

Field measurements of the indoor climate have been carried out in 128 lightweight timber-frame detached houses in Finland and in Estonia during the years 2002-2005. The temperature and relative humidity were continuously measured in bedrooms, living rooms and outdoors for each house at 1-hour intervals over a 1-year period. The studied timber-frame detached houses had different types of heating and ventilation systems, envelope structures and indoor surface hygroscopic properties. An extended period of high indoor temperatures during summer suggests that thermal comfort was not considered in the original design. During winter, despite of almost ideal average temperatures, the variations in temperature was larger than expected to be produced by modern heating systems and well insulated envelopes. Minor differences in the daily amplitude of the relative and absolute humidity were shown in the comparison of the hygroscopic and non-hygroscopic cases. A very similar dampening effect was seen when balanced ventilation was compared to other ventilation systems. The building orientation and a large number of uncontrolled factors had an important effect on the indoor climate because the variation of indoor climate parameters was much higher between single houses than between subdivisions compared