Stair rise and going relationship

550 mm

Every figure for this topic is on one page: Stair dimensions and handrail heights in UK homes

Staircases must be dimensioned such that the relationship between the rise (R) and the going (G) falls within prescribed limits for safety and comfort, typically expressed as 2R + G between 550mm and 700mm. Accurate location and fixing of the staircase are essential to ensure the string is at the correct angle and all treads are level.

Basis in regulation

Part K
Approved Document K
Read the source

How to check it on site

Verify the 2R + G calculation for the staircase and check that treads are level and the strings are securely fixed at the correct angle.

Common failure

Incorrect rise and going relationships can result in an uncomfortable or unsafe staircase; unlevel treads are a significant trip hazard.

Last updated 23 August 2026. This is our editorial summary of publicly available regulation, not building control approval or a warranty determination.

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