Measurements of the air temperature and air velocity were carried out in four buildings without air-conditioning using a newly developed anemometer whose sensitivity allows the examination of the dynamic behaviour of air movements. Recent results describing the physical reasons of draft problems were employed in order to re-examine the correlation between air movements and draft problems in a building. From the resulting evaluation criteria follows that besides, the environmental temperature and the mean air velocity, the magnitude of the turbulent fluctuations is important .
During winter periods in four types of newly built terraced dwellings and in apartments of a flatbuilding,the daily behaviour and motivations of the inhabitants with respect to airing and ventilation have been studied. In total the information was obtained from 279 households. A combination of verbal interviews, diaries and technical measurements are used as methods of investigation. On basis of the findings,calculations can be made about air flows in occupied dwellings.