Technical Booklet E Fire Safety·Page 68·2.74
External walls adjacent to protected stairways
Where a protected stairway projects beyond, is recessed from, or is in an internal angle of the external walls, unprotected areas in adjacent external walls must be separated by a minimum distance of 1.8 m.
Where a protected stairway projects beyond, is recessed from, or is in an internal angle of the external walls of the building – the distance between any unprotected areas (see Section 5) in the adjacent external walls of the building and an unprotected area in the external walls of the protected stairway should not be less than 1.8 m, as shown in Diagram 2.10.
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