In k1 section 1 21 spiral and helical stairs the regulations refer you to a british standard bs5395 2 1984.
Spiral staircase regulations scotland.
This document is summarised in the table below with categories given for each spiral application and the relevant maximum riser heights and minimum widths.
Uk staircase regulations there are three main building regulations that relate to staircases generally referred to as part k m b.
K1 building regulations is the approved document which covers stairs ladders and ramps.
The document governing spiral staircase building regulations in the uk is british standard 5395 part 2.
When considering the building regulations for spiral staircases in the uk it is worth being aware that these can differ in scotland.
Overall staircases in scotland are likely to be larger in width and length and take up more space than those elsewhere in the uk.
Bs 5395 part 2 1984 this states that a spiral serving 1 habitable room should have a 600mm clear width max rise of 220mm and centre going of more than 145mm.
Spiral staircases page of continental stairs.