Technical Booklet H Stairs Ramps Guarding and Protection from Impact·Page 31·3.31
Number of rises per flight
Each flight must have between 2 and 12 rises, though exceptions may apply in constrained existing buildings.
There should be not less than 2 rises and not more than 12 rises in each flight. There may be exceptional circumstances where a different rise or greater number of rises in a flight is more appropriate e.g. where there are dimensional constraints imposed by an existing building.
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