Expresses air infiltration rate measured using tracer gas in 2 similar town houses in terms of wind speed, wind direction, indoor-outdoor temperature difference, average rate of boiler firing and fraction of time that doors are open. Method yielded reproducible rates of air infiltration within 0.1 air exchanges per hour in any single one-week run once outside temperature, wind speed and wind direction were allowed for. States results partly reveal set of physical principles determining house air exchange rates which are so far poorly understood.
Sets out simplified analysis of thermal load imposed by infiltration of cold outside air into interior of heated building as function of prevailing wind speed and difference between internal and external temperatures. Treats infiltration loss, structure loss, effect of wind speed on loss. Summarises these values in tables. Concludes incidence of wind speeds in excess of those used for calculation of heat losses at design condition can have a significant effect on internal temperatures. Notes implications for non-attainment of design temperatures in intermittently heated buildings.