Staircase Calculator
Size a domestic staircase from your floor to floor height, with a Building Regs (Part K) sense check.
Sense checked against Approved Document K for private stairs: max rise 220 mm, min going 220 mm, max pitch 42°, and 2×rise + going between 550 and 700 mm. Always confirm against current regs and your specific job.
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How to use the staircase calculator
Enter the total floor to floor height and the calculator works out the number of risers, the individual rise and going, and checks them against UK Building Regulations for domestic stairs. It is a fast way to sense check a staircase before you order timber or commit to an opening size.
Frequently asked questions
How do I calculate the number of stairs?
Divide the total floor to floor height by a comfortable rise of around 190, 200 mm and round to a whole number of risers; that fixes the exact rise per step.
What are the Building Regs for domestic stairs?
For private stairs in England the maximum rise is 220 mm, the minimum going is 220 mm, and the pitch must not exceed 42°. Always confirm against the current Approved Document K.
What is the rise and going of a staircase?
The rise is the vertical height of each step; the going is the horizontal depth of each tread. Together they set how steep and comfortable the stairs feel.