Ventilation: A behavioural approach

Behavioural studies of the window-opening habits of families in one hundred and twenty three houses show a strong seasonal pattern. During winter window opening is closely related to moisture level in the external air. In summer it is more closely linked to mean daily temperature. There are wide differences between families, with larger families having more open windows. Re-examination of ventilation criteria suggests three seasons, one in deep winter which needs minimum adequate air for body odour removal, the second in spring/autumn for controlling moisture and the third in summer for cooling.