Technical Booklet E Fire Safety·Page 134·5.2
Fire Resistance of External Walls
External walls must have appropriate fire resistance periods as specified in Section 4, except in unprotected areas determined by paragraphs 5.10 to 5.12.
The external walls of a building are elements of structure and other than those areas which may be unprotected (as determined in accordance with paragraphs 5.10 to 5.12) should have the appropriate period of fire resistance given in Section 4.
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