Technical Booklet E Fire Safety·Page 42·2.18
Enclosure of existing stairway - general requirements
Existing stairways in dwellinghouses must be enclosed with fire-resisting walls and either extend to a final exit or lead to at least two separate escape routes at ground level.
The existing stairway should be enclosed by fire-resisting walls and either –
(a) extend to a final exit as shown in Diagram 2.3(a); or
(b) lead to at least two escape routes at ground level, each delivering to a final exit and separated from each other by fire-resisting construction and self-closing fire doors as shown in Diagram 2.3(b).
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