Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 20·2.14
Stepped approach requirements
A stepped approach to a dwelling must have flights of at least 900 mm width, maximum rise per flight of 1800 mm, step dimensions between 75–150 mm rise and minimum 280 mm going, closed steps, maximum 16 steps per flight, and landings of at least 900 mm with a handrail on one side.
A stepped approach should have –
(a) a flight or flights with an unobstructed width of not less than 900 mm;
(b) a rise of not more than 1800 mm in each flight of steps;
(c) steps with a uniform rise of not less than 75 mm and not more than 150 mm;
(d) steps with a uniform going of not less than 280 mm (which in the case of tapered treads should be measured at a point 270 mm from the narrow end);
(e) steps that are not open and have a suitable profile such that the risk of tripping is reduced. See Diagram 2.4;
(f) a maximum of 16 steps in a flight;
(g) landings with an unobstructed length of not less than 900 mm; and
(h) a suitable continuous handrail (see paragraph 2.15) on one side of the flight and at an intermediate landing where the flight comprises three or more steps.
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