Natural ventilation is of increasing interest in building industry because of recent focus on environmental concern, considered with both comfort and economical criteria. The aim of this study is to investigate how wind may induce natural ventilation, with focus on wind incidence and large scale environment density influences. These parameters modify flows inside and outside buildings. Numerical dynamic simulations are achieved for a standard office building using pressure coefficients obtained from a parametrical model. Simulations allow to describe inside building air flow for three incidences: 0 degrees, 45 degrees, 90 degrees and three theoretical environments: open, suburban and urban. Originality of this study is to work with both vertical and horizontal pressure coefficient gradients. Results show how important horizontal gradients are in air flow comprehension. Urban wind driven ventilation potential is also discussed. Some words are said on existing tools limitations. The need for further studies is illustrated in order to obtain handy pressure coefficients prediction tools and to optimize openings mechanical regulation. The all study falls under the step of sustainable architecture. (c) 2004 Elsevier B.V. All rights reserved.