Technical Booklet E Fire Safety·Page 37·2.5
Emergency egress windows for upper storeys
Every habitable room on an upper storey not more than 4.5 m above ground level without alternative escape routes should have an emergency egress window complying with paragraph 2.9. One window may serve two rooms if both have direct access to the stairway enclosure and can be accessed between rooms without passing through the stairway.
Every habitable room, on an upper storey not more than 4.5 m above ground level that does not have alternative escape routes, should have an emergency egress window complying with paragraph 2.9 for escape purposes. However, an emergency egress window may serve two such habitable rooms provided that – (a) both rooms have their own access to the stairway enclosure; and (b) it is possible to gain access, via a communicating door between the rooms, to the window without passing through the stairway enclosure.
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