Abstract
It is difficult to measure directly the coefficient of wind pressuer c_1 (windward) and c_2 (leeside) that are necessary for estimation of cross ventilation amount. The author obtained values of c_1 and c_2 as shown in Tab. 1 or Fig. 3, from the theoretical formulas (5) and (6) by the abssrved values of qi (wind velocity in inlet), q_0 (wind velocity in outlet) and q (wind velocity in outdoor). The coefficients of wind pressure obtained here fit those of the theoretical values.
