Heat loss in buildings as a result of infiltration.

Heat load from passage of cold outside air to building interior is function of wind speed and outdoor air temperature. Analyses meteorological data to determine suitable design conditions for accurate assessment of infiltration heat losses. Terms multiple of wind speed and indoor-to-outdoor air temperature 'wind-temp number' using it as measure of infiltration heat loss caused by wind. Plots these numbers for range of outdoor air temperatures and wind directions. States that peak values of summation of fabric heat loss and wind and stack induced infiltration heat loss should be used for design purposes.