Three numbers decide whether a staircase feels comfortable: the rise of each step, the tread you put your foot on, and the headroom above you. Get these right on the drawing and nobody will notice the stairs. Get them wrong and everybody will.
The three numbers
- Rise: 150–175 mm (6–7 in). Above about 180 mm the stair feels steep, especially for elderly family members.
- Tread: 250–300 mm (10–12 in), excluding the nosing.
- Headroom: at least 2.1 m (about 7 ft), measured vertically from the nosing line to the lowest overhead obstruction.
A useful check is 2 × rise + tread = 550–700 mm. A 160 mm rise with a 275 mm tread gives 595 mm, a comfortable stair.
Width and landings
For a house, 900 mm (3 ft) is the minimum clear width. 1,050 mm (3.5 ft) lets you move furniture up without a struggle. A landing should be at least as deep as the stair is wide, and no single flight should have more than about 12–15 steps.
Working it out
With a 10 ft (3,050 mm) floor-to-floor height and a 160 mm rise, you need 19 risers. A dog-legged stair splits these into 10 + 9, which needs roughly 8 × 12 ft of floor area including landings. That space has to be kept on every floor, which is why the staircase is the first thing we fix on a small plot.
The headroom mistake
The most common site error is a beam at the landing or mid-flight that drops into the headroom. The drawing looked fine in plan, but nobody checked the section. The fix after casting is ugly and expensive. Every staircase we draw is checked in section for beam positions before the frame is released.
Vastu note
Staircases are generally preferred in the south, west or south-west parts of the house and climbing clockwise. They should not be placed in the north-east or at the centre (Brahmasthan). Try our Vastu validation tool to check your own plan.
