BS 6375-1(1989) : 1989

Foreword
Committees responsible
Classification
1 Scope
2 Definitions
3 Classification
4 Test procedures
5 Test for air permeability
6 Test for watertightness
7 Tests for wind resistance
Appendices
A Guidance on the selection and specification of
   windows for weathertightness
B Methods of calculating design wind pressure
Tables
1 Exposure categories
2 Ground roughness categories
3 Combined internal and external pressure coefficients
4 Design wind pressure
Figures
1 Air permeability limits for windows with opening
   lights
2 Window types and air penetration
3 Basic wind speed

Describes classification of windows for weathertightness in terms of exposure categories related to test pressure levels for air permeability, watertightness, and wind resistance. Applicable to all types of windows in which any frame member is no longer than 3m, and includes windows in which the opening lights are not fully framed. Excludes patent glazing, curtain walls that span across horizontal structural members of floors but includes the opening lights within a patent glazing or curtain walling system.