Staircase building regulations: Wales
Written by Scott Jones, The Stair Guys, independent staircase measuring and sourcing specialists·Last updated
Almost everyone treats England and Wales as one jurisdiction for stairs. For the geometry of a private staircase, that is wrong, and it is wrong in the direction that gets a stair rejected. Wales runs its own Approved Document K, and it is not England's. The Welsh document is the 1998 edition incorporating the 2000 and 2010 amendments. England moved on to a 2013 edition that is marked "for use in England" and does not apply in Wales. Two different documents, written fifteen years apart, and the private stair numbers in them are not the same.
The going is the difference that matters
In England a private stair needs a going of at least 220mm. In Wales it does not. The Welsh document sets out the private stair as two bands: a rise between 155mm and 220mm used with a going between 245mm and 260mm, or a rise between 165mm and 200mm used with a going between 223mm and 300mm. Whichever band you are in, the minimum going is 245mm or 223mm. It is never 220mm. Build to the England figure in Wales and the stair does not meet the Welsh guidance, which is the sort of thing that surfaces at the worst possible moment, when it is already in.
| England (AD K 2013) | Wales (AD K 1998, incorporating 2000 and 2010 amendments) | |
|---|---|---|
| Rise, private stair | 150mm to 220mm | 155mm to 220mm, or 165mm to 200mm (two bands) |
| Going, private stair | 220mm to 300mm | 245mm to 260mm (with a 155-220mm rise), or 223mm to 300mm (with a 165-200mm rise) |
| Minimum going | 220mm | 245mm or 223mm, depending on the rise band |
| Maximum pitch, private stair | 42 degrees | 42 degrees, the same |
| Headroom | 2m | 2m, the same |
| Loft conversion headroom | 1.9m at the centre, 1.8m at the side | 1.9m at the centre, 1.8m at the side, the same |
| Handrail height | 900mm to 1000mm | 900mm to 1000mm, the same |
| 2R + G | "the normal relationship", 550mm to 700mm. Not a limit. | "the normal relationship", 550mm to 700mm. Not a limit. |
| Stair categories | Private, utility, general access | Private, institutional and assembly, other stair |
What genuinely is the same
Plenty does carry across, and it is worth being precise about which parts. Headroom is 2m on the access between levels in both nations, and both allow the same loft conversion relaxation of 1.9m measured at the centre of the stair width, reducing to 1.8m at the side. Handrail height is 900mm to 1000mm in both. The maximum pitch for a private stair is 42 degrees in both. So the shape of the stair in section is broadly the same. It is the tread depth, and the categories the document sorts stairs into, where the two nations part company.
One more that catches people out in both nations: the 2R + G figure of 550mm to 700mm is not a rule. Both documents call it "the normal relationship" between rise and going. It is a sanity check, not a limit, and you can build a compliant stair that falls outside it.
Stair width: Wales does not give a figure
The Welsh document is explicit that it does not set one. Paragraph 1.11 says that no recommendations for minimum stair widths are given, and leaves it to the designer. So if someone tells you there is a minimum staircase width in the Welsh building regulations, ask them which paragraph, because there is not one to point at.
The other real difference: accessibility and M4
England has, since 2015, split its accessibility rules into three tiers, M4(1), M4(2) and M4(3), where a planning condition can require the higher tiers. The higher tiers bring in things like a minimum 850mm stair width to allow a future stairlift. Wales did not adopt that system. Welsh Approved Document M remains the single, earlier accessibility standard, with no M4(2) or M4(3) optional categories. So there is no automatic 850mm stairlift-width rule and no through-floor lift reservation built into the Welsh building regulations for an ordinary dwelling.
Where accessible-housing rules do come from in Wales
That does not mean accessibility is ignored in Wales. Where accessible or adaptable homes are required, it comes through the planning system, from a Local Development Plan policy imposed as a planning condition, rather than through the building regulations. If your project is subject to such a condition, the local planning authority will set the standard it wants, and building control enforces against that condition. So in Wales the question to ask is not just "does it meet the building regs" but "is there a planning condition on accessibility", because that is where any stairlift-width or adaptability requirement will sit.
Frequently asked
Are the staircase building regulations different in Wales?+
Yes, and more than most people think. Wales uses its own Approved Document K, the 1998 edition incorporating the 2000 and 2010 amendments, not England's 2013 document. Headroom, handrail height and maximum pitch are the same, but the private stair rise and going are different, and Wales sorts stairs into different categories.
What is the minimum going for a private staircase in Wales?+
At least 245mm if the rise is between 155mm and 220mm, or at least 223mm if the rise is between 165mm and 200mm. It is not 220mm. That is the England figure and it is not enough in Wales.
Why do people think Wales uses 220mm like England?+
Partly because England and Wales are treated as one jurisdiction for most things, and partly because the figure 220mm does appear in the Welsh document. It is at paragraph 1.24 and it applies only to alternating tread stairs in a loft conversion, where there is not enough space for a normal stair. It is not the general private stair figure.
Is the maximum pitch still 42 degrees in Wales?+
Yes. The Welsh document states the maximum pitch for a private stair is 42 degrees, the same as England.
Is there a minimum staircase width in Wales?+
No. Paragraph 1.11 of the Welsh Approved Document K says that no recommendations for minimum stair widths are given, and leaves it to the designer.
Does Wales use England's M4(2) and M4(3) accessibility standards?+
No. Wales never adopted England's M4(2) and M4(3) optional requirements, so there is no built-in 850mm stairlift-width rule or through-floor lift reservation in the Welsh building regulations for an ordinary dwelling. Where an accessible-housing requirement applies in Wales it normally comes through the planning system instead.
Sources
Primary sources we used and reconciled before publishing.
- Approved Document K: protection from falling, collision and impact. For use in Wales, 1998 edition incorporating 2000 and 2010 amendments (Welsh Government). Private stair rise and going at para 1.3(a); headroom at para 1.10; 2R + G at para 1.5; stair widths at para 1.11; alternating tread stairs at paras 1.23-1.24.
- Amendment slip: amendments to Approved Documents, September 2013 (For use in Wales). Confirms Approved Document K remains the 1998 edition and amends only materials and workmanship text.
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