The project measurement of building tightness is completed, but many open questions remain. Rakkenustentiiviystutkimus valmis - avoimia kysymyskia riittaa viela.

Reports conclusions from projects investigating the tightness of buildings sponsored by the Ministry of Trade and Industry. Describes factors influencing ventilation such as size and shape of building, location, distribution of leakage points, interior air flow paths and the design and control of ventilation. Wind condition and temperature difference are the only driving forces in natural ventilation, in mechanical ventilation the temperature has only a limited influence but the wind may cause considerable draught in an untight building. Points out that mechanical ventilation seems to be the right solution to air quality problems in tight houses.