Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 27·3.16
Number of rises in a flight
A flight should have a maximum of 16 rises and a minimum of 2 rises, except that single steps are permitted in specific locations within dwellings.
The number of rises in a flight should be a maximum of 16 and a minimum of 2. However, notwithstanding the provisions of paragraph 3.19, a single step may be provided –
(a) at the bottom of a stair in a dwelling;
(b) at an entrance to a dwelling;
(c) between any enclosed porch, outhouse or conservatory and the remainder of a dwelling;
(d) where it provides access to a small room; or
(e) between a garage and a dwelling.
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