Energy Efficiency and Indoor Climate of Apartment Buildings in Estonia

The years 1960-1990 saw an extensive construction of apartment buildings in Estonia. In the 1970s the specific heat consumption of apartment buildings made about 380 kWh/m2 per year. The 1990s saw the beginning of the renovation of heat substations, heating and ventilation systems and building envelopes. The renovation of windows in old apartment buildings was accompanied by problems in the indoor climate. The problem of indoor climate seriously affects partly renovated old apartment buildings. With the help of simulation programs energy conservation achievable with renovation and indoor climate has been analysed in apartment buildings. Increase in energy efficiency in buildings with the help of air handling units (AHU) with heat recovery is analyzed. In old apartment buildings one of the possible solutions is the air change arrangement by room heat recovery units and programmable exhaust ventilators in toilets, bathrooms and kitchens.