Technical Booklet E Fire Safety·Page 85·3.9
Definition of wall for fire safety purposes
For wall and ceiling lining performance, walls include glazed surfaces (except in doors) and ceiling slopes exceeding 70° to the horizontal.
For the purposes of the performance of wall and ceiling linings –
(a) a wall should include –
(i) the surface of glazing (except glazing in a door); and
(ii) any part of a ceiling which slopes at an angle of more than 70º to the horizontal;
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