Staircase Calculator
Risers, treads, going and concrete for a straight or dog-legged RCC stair.
Free tool by EngineeringNepal.com.np · Results are for guidance; check critical figures with a qualified engineer.
Designing the steps of a house stair
The stair is one of the first things to get right on a house plan in Nepal, because it fixes the size of the stair hall and the floor heights. Too high a riser makes the stair tiring for elders and children; too short a tread makes it unsafe. This calculator takes the floor to floor height and your preferred step sizes, then finds the number of risers, the exact riser height, the going and the concrete needed for an RCC stair.
How the numbers are worked out
- Number of risers = floor to floor height ÷ maximum riser, rounded up. For a dog-legged stair the count is made even so the two flights are equal.
- Actual riser = floor height ÷ number of risers. Every step must be the same height.
- Treads per flight = risers in that flight − 1.
- Going = number of treads × tread width. Add the landing width to get the length of the stair hall.
- Comfort rule: 2R + T should be about 600 to 640 mm. Values from 550 to 700 mm are generally acceptable.
Common sizes for residential stairs
Many house stairs in Nepal use a riser of 150 to 175 mm (about 6 to 7 inches) and a tread of 250 to 300 mm (10 to 12 inches), with a clear width of 0.9 to 1.2 m. Public buildings need wider stairs and lower risers. Check the building bye-laws of your municipality and the relevant parts of the Nepal National Building Code before finalising a design.
Concrete quantity
The RCC volume adds the inclined waist slab (slope length × width × thickness), the triangular steps (½ × riser × tread × width each) and, for a dog-legged stair, a mid landing of about width × twice the width. Use the concrete calculator to turn this volume into cement bags, sand and aggregate, and the steel weight calculator for the reinforcement.
Frequently asked questions
What floor height should I enter?
Use the finished floor level to finished floor level, including floor finishes. A typical floor height in a Nepali house is about 2.9 to 3.2 m (9.5 to 10.5 ft).
Why is my riser smaller than the maximum I entered?
Because the floor height is divided into equal steps. If 3.0 m needs 18 risers, each one is 166.7 mm, which is below the 175 mm maximum.
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