Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 23·3.9
Stair Headroom Requirements
Stairs must provide a minimum clear headroom of 2000 mm, measured vertically from the pitch line and landing level; roofspace conversions in dwellings may have reduced headroom where demonstrated necessary.
A stair should have a clear headroom of not less than 2000 mm over its full length and width. Headroom is measured vertically from the pitch line of the flight and the level of the landing. See Diagram 3.2(a). For roofspace conversions in a dwelling, where it can be demonstrated that there is not enough space to achieve a clear headroom of at least 2000 mm, it would be reasonable for a stair to have headroom as shown in Diagram 3.2(b).
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