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Code and standard reference

UK Building Regulations Part K Stairs

Last reviewed · BuildMath editorial team

Approved Document K lists a maximum 220 mm rise, minimum 220 mm going, and maximum 42-degree pitch for private stairs, with separate rules for other stair categories, headroom, landings, handrails, and guarding. These values are a navigation aid only: use the current official document and the requirements adopted for the project location.

Limit table

UK Building Regulations Part K Stairs planning summary
ItemLimit or ruleReferenceVerification note
Private stair riseMaximum 220 mmTable 1.1Other stair categories use different limits.
Private stair goingMinimum 220 mmTable 1.1Measure in accordance with the document diagrams.
Private stair pitchMaximum 42°Table 1.1Rise and going must also comply.
HeadroomNormally 2.0 mSection 1.10Loft conversions have illustrated alternatives.
LandingsLevel and generally at least stair widthSection 1.20 onwardDoor swing and obstruction rules apply.

How to use this code summary

  1. Confirm which code edition and local amendment applies to the project address.
  2. Measure the actual completed geometry, not only rough framing or nominal dimensions.
  3. Compare the calculator output with every relevant row and exception in the primary source.
  4. Escalate structural, accessibility, egress, guard, and fall-protection questions to the authority or qualified professional.

Calculators that use this reference

Frequently asked questions

Is this the complete code text?

No. This is a focused planning summary with a direct primary-source link. Definitions, exceptions, local amendments, and adjacent sections can change how a limit applies.

Which edition should I use?

Use the edition adopted by the authority having jurisdiction for the project address, including local amendments.

Can the calculator certify compliance?

No. It can flag a value against a displayed planning limit, but approval belongs to the authority, designer, or qualified professional.

Why is the source linked?

The source link lets readers and answer engines distinguish a cited rule from an unsupported numerical claim.

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