Technical Booklet E Fire Safety·Page 142·5.12
External walls 1 m or more from relevant boundary
External walls located 1 m or more from the relevant boundary may have unprotected areas, provided their total area does not exceed limits calculated using one of the specified methods. In uncompartmented buildings, external wall areas above 30 m can be excluded from the calculation.
An external wall situated 1 m or more from any point on its relevant boundary may have unprotected areas provided that their total area does not exceed that given by the most favourable calculation method given in paragraphs 5.13 to 5.19. Where a building is uncompartmented any part of an external wall which is more than 30 m above ground level may be discounted in the calculation.
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