Technical Booklet R Access to and Use of Buildings·Page 27
Lobby width requirements
Unobstructed clear lobby width must be at least the width of the widest door leaf plus 300 mm or 1200 mm minimum for single leaf doors, and 1800 mm minimum for double leaf doors.
The unobstructed clear lobby width should be - a) for lobbies served by single leaf doors - not less than the width of the widest door leaf plus 300 mm or not less than 1200 mm whichever is the greater; and b) for lobbies served by double leaf doors - not less than 1800 mm.
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