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Half-turn stair calculator for U-shaped layouts
A half-turn stair folds the climb into two parallel flights connected by a landing. It can reduce the required room length, but flight spacing, landing size, opening, and headroom all need to work together.
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Best for
- • Compact rectangular stair halls
- • Layouts needing two parallel flights
- • Comparing footprint against a straight stair
Measurements to take
- • Finished floor-to-floor height
- • Lower and upper flight lengths
- • Flight width and gap
- • Turn direction
- • Opening length and floor thickness
Results you get
- • Step distribution across both flights
- • Riser height and flight goings
- • Pitch and Blondel values
- • Estimated minimum headroom
- • Landing geometry and parts schedule
What to have reviewed
The current half-turn export summarizes the design for review. A qualified builder or designer still needs to resolve support, landing construction, stringer connections, guarding, and local regulatory requirements.
Common questions
What is a half-turn staircase?
It is a U-shaped stair with two flights traveling in opposite directions, connected here by a rectangular landing.
Why compare both flight lengths?
The available length for each flight affects its going and pitch. Comparing both prevents one flight from becoming the limiting geometry.