A method for the assessment of the wind-induced natural ventilation forces acting on low rise building arrays

Whilst the assessment of the natural ventilation rates of low-rise buildings is an area of growing concern in the continued search for greater interior comfort standards, this concern is perhaps reflected more in our awareness of the energy impact which this source of heat loss has in the present financial climate. It is surprising therefore that so little is known about air infiltration in the low rise buildings, which continue to comprise the majority of our housing stock. The relatively small amount of data which exists relates only to isolated buildings despite the fact that other spheres of fluid mechanics have for some time recognised the importance of proximity effects in the prediction of fluid flow phenomena. It is the intention of this paper to describe a series of wind tunnel investigations which have led to the development of a procedure by which it is possible to estimate the wind pressure forces which act on a low-rise building which itself is part of a large group of similar buildings. The use of this technique makes it possible to allow for the building form, the parameters which describe the array in which it is situated, the upstream building conditions and the orientation of the wind. Wind speed maps are included in an appendix so that the prediction technique may be applied to the determination of natural ventilation forces on buildings situated in parts of the UK.