Staircase Building Regulations...what you need to know!

As we are often asked whether certain staircases comply with building regulations, we thought it may be useful to inform our clients as to the restrictions and requirements surrounding many aspects of home improvements as well as the building regulations pertinent to staircases. Although we sell stairs of diameter 100cm on this site, that does not necessarily mean they comply with all regulations.


Staircase category                i.e.                 Min-max rise per tread      Min clear widths per tread      Min centre goings per tread


A                                  Small private stair                170-220mm                                600mm                                      145mm


B                                 Main stair of a house          170-220mm                                800mm                                       190mm


C                                 Semi Public                          170-220mm                                800mm                                       230mm



We always suggest you contact your local council prior to any work. However click below for part K of the building regulations section BS5395 charting all the relevant information with regard to the building regulation requirements for staircases.













Domestic spiral staircases come under 2 aspects of the Building regulations depending upon their usage


Primary stair - For a main stair serving 2 or more habitable rooms you require a 800mm clear width (900mm in Scotland), max rise of 220mm and a centre going of 190mm. Generally 1800mm diameter staircases and above are used in this instance.


Secondary staircase - For a spiral serving 1 habitable room it should have a 600mm clear width, max rise of 220mm and centre going of more than 145mm.



String / Stringer - the structure that supports the treads and risers which can be in wood or steel

Tread - the part of the stair that you walk on

Going - The individual going is the horizontal measurement from face of riser to face of riser

Riser - the vertical portion between each tread on the stair.  There are closed or open risers

Rise - The individual rise is the vertical measurement from top of tread to top of tread

Nosing - the front part of the tread that overhangs the riser, they actually overlap each other slightly.


Staircase Terminology...some helpful explanations