Technical Booklet E Fire Safety·Page 40·2.14
Additional provisions for dwellinghouses with multiple storeys above 4.5 m
Dwellinghouses with two or more storeys above 4.5 m must have all upper storeys served by a protected stairway. Storeys over 7.5 m above ground level must have an alternative escape route with its own final exit, with the protected stairway subdivided by fire-resisting construction at or about 7.5 m.
In a dwellinghouse with two or more storeys more than 4.5 m above ground level –
(a) all storeys above the storey containing the final exit should be served by a protected stairway which complies with paragraph 2.12(b); and
(b) each storey that is over 7.5 m above ground level should have an alternative escape route leading to its own final exit. Where access to an alternative escape route is through the protected stairway, the protected stairway should be subdivided by fire-resisting construction at or about 7.5 m above ground level.
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