The tightness of buildings studied by international cooperative group. Byggnaders tathet studeras i internationell samarbetsgrupp.

Notes emerging importance of airtightness and preparation of `Air Infiltration Handbook' by Sweden. Discusses the work of the Air Infiltration Centre under the auspices of the International Energy Agency. Reports on second AIC conference hosted by Sweden in September 1981. Discusses main topics presented at the conference dominated by the need for `controlled ventilation' and the problem of measurement.