Technical Booklet E Fire Safety·Page 143·5.16
Method 1 - Small residential buildings unprotected areas limits
For small residential buildings in Purpose Groups 1 and 2(b) not exceeding three storeys and 24 m in length, the maximum total unprotected area is determined by the minimum distance to the relevant boundary, with no limit at 6 m distance.
This method may only be used for buildings in Purpose Groups 1 and 2(b) which do not exceed three storeys in height and are not more than 24 m in length. The maximum total area of unprotected areas in the side of a building should not exceed that given in Table 5.2 for the relevant minimum distance between that side and its boundary.
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