Natural ventilation in office type buildings: results from design case studies.

Natural ventilation can be a part of a strategy for a good indoor air quality. It can also be a way to realise night time ventilation during warm periods. In this latter case, the aim is to cool down the thermal mass of the building to obtain a better thermal comfort during daytime. Night time ventilation requires high ventilation rates and sufficient accessible thermal mass. The ventilation openings have to be well designed to avoid undesirable effects like rain, pollution and burglary. However a successful design for summer comfort depends on a lot more: solar and internal gains must be well controlled. The summer comfort can be evaluated in advance by means of thermal simulations. This paper presents four Belgian buildings in which natural night ventilation for summer comfort is a critical issue; it are two new buildings and two renovated buildings.