Directional driving rain indices for the United Kingdom - computation and mapping (Background to BSI Draft for Development DD93)
THIS PUBLICATION HAS BEEN ARCHIVED.
Whilst this publication can still be purchased some of the information in it has been superseded by more recent research and standards. The BRE Group does not accept any responsibility whatsoever for any loss or damage, including - without limitation - indirect or consequential loss or damage arising from use, or loss of use, of data or profits arising out of, or in connection with, the use of this document.
In 1971 the Building Research Station published Digest no.127 "An index of exposure to driving rain", by R E Lacy, based on work done at BRS during the 1960s.
A BRE report "Driving-rain index: annual mean driving-rain index in the United Kingdom with proposed revised rules for assessing local exposure" by Lacy was published by HMSO in 1976.
The BRE publications were superseded by the British Standard Draft for Development DD93: 1984 "Methods for assessing exposure to wind-driven rain", which gives the full design method and driving rain maps for the whole of the UK, and then by BS 8104: 1992 "Code of practice for assessing exposure of walls to wind-driven rain".
Designers should now use BS 8104.
These indices are relevant to the weathering and staining of building facades and assessing the risk of rain penetration. This report (BR59) discusses the background to the production of DD93, including the work of P.G.F. Caton of the Meteorological Office.