Technical Booklet R Access to and Use of Buildings·Page 28·4.4
Minimum unobstructed width of corridors and passageways
Corridors and passageways must have an unobstructed width of at least 1200 mm, with minor projections ignored and larger projections requiring suitable directional guidance.
A corridor or passageway should have an unobstructed width of not less than 1200 mm. Minor projections (e.g. skirtings, architraves, etc.) may be ignored. However, where a projection into the corridor or passageway is unavoidable (e.g. at an archway in an existing building) and is more than 100 mm, that projection should have a suitable means of directing people around it.
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