Going of a tapered tread

Measured at the centre of the flight; at least 50 mm at the narrow end

Winder or tapered tread in a private stair

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

Read the full answer

Where the going of a tapered tread is measured, and the minimum going at the narrow end.

Basis in regulation

Part K
Approved Document K
Read the source

How to check it on site

Measure the going on the centre line for flights under 1 m wide, and check the narrow end of every winder rather than sampling one.

Common failure

Winders set out to fit the stairwell, leaving a narrow end that is effectively a point.

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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