Technical Booklet E Fire Safety·Page 37·Diagram 2.1
Diagram 2.1 – Emergency egress window dimensions and positioning
Diagram 2.1 specifies dimensions for emergency egress windows in roof space conversions of 2-storey dwellinghouses, with different requirements for dormer windows (800–1100 mm bottom of opening) and roof windows (600–1100 mm bottom of opening), requiring a clear opening not less than 0.33 m² with minimum 450 mm height and width.
Emergency egress windows from roof space conversions of 2 storey dwellinghouses. (a) Dormer window – bottom of opening 800–1100 mm above floor level at eaves. (b) Roof window (rooflight) – bottom of opening 600–1100 mm above floor level. Notes: (1) Clear window opening not less than 0.33 m² in area and at least 450 mm high and at least 450 mm wide. (2) Window located to facilitate rescue by ladder from the ground. (3) The window may be in the end wall of the dwellinghouse instead of the roof as shown.
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