The performance of ventilation in Soviet design apartment buildings in Estonia.

The purpose of the study was to measure the performance of natural ventilation in 5- and 9- storey apartment buildings, and to offer solutions for the improvement of ventilation. In the four most common building types, the functioning of the old ventilation system was measured during a spring and summer period. The economically feasible improvement solutions, as installing the auxiliary fans and mechanical exhaust ventilation, were analysed with measurements and calculations. The old natural ventilation system with stacks and leaky windows can maintain a certain basic level of ventilation. The air change was in an average two-room flat 0,4 ... 0,5 l/h during the measuring period. The simplest and economically most feasible way for improving ventilation is to install in the first stage the kitchen exhaust fans, and in the second stage, the exhaust airflows in bathrooms and toilets can be improved by installing the fans on the top of the stacks.