Technical Booklet E Fire Safety·Page 42·2.21
Fire separation of new storey from existing building
A new storey must be separated from the rest of the dwellinghouse by fire-resisting construction, with the stairway either continuing the existing enclosure or separated from existing areas by fire-resisting construction.
The new storey should be separated from the rest of the dwellinghouse by fire-resisting construction. The new stairway should either –
(a) rise as a continuation of the existing stairway and enclosure, in which case the stairway should be separated from the new accommodation by fire-resisting construction; or
(b) be separated from the existing stairway and the rest of the dwellinghouse by fire-resisting construction.
Any door in new fire-resisting construction should be a self-closing fire door.
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