Wind-induced ventilation is studied analytically in a simple one-zone structure and numerically in a three-zone building. The paper focuses on the wind effect, but because wind influence cannot be treated independently of other main driving forces, the wind effect is studied with and without stack effect and mechanical exhaust. The analytical part describes the basic equations that are necessary to predict ventilation rates. These equations are applied to a simple structure to make it possible to study the principal meamng and influence of each one of the parameters in an analytical way. The magnitude and importance of each parameter are discussed.

The numerical part shows an actual calculation of a multi-zone structure. The infiltration for each zone is shown as a function of wind effect alone and in combination with stack effect and mechanical exhaust. This demonstrates the non-trivial interaction between the different driving forces.