Technical Booklet E Fire Safety·Page 59·2.58
External escape routes
Where an external escape route (other than a stair) is beside an external wall, the wall within 1.8 m horizontally of the escape route must be of fire-resisting construction, extending 1.1 m above and 9 m below the level of the route.
Where an external escape route, other than a stair, is beside an external wall of the building, that part of the external wall within 1.8 m (measured horizontally) of the escape route should be of fire-resisting construction 1.1 m above and 9 m below the level of the route as shown in Diagram 2.11 (see page 61).
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