Short answer
What is the standard size of stairs for a house in India? The Model Building Bye-Laws 2016, clause 4.17, give a dwelling stair a minimum width of 1.0 m, a tread of at least 250 mm, a riser of at most 190 mm, 12 risers per flight and headroom of 2.2 m. NBCS 2026 says 175 mm for a one or two family dwelling. These are model and code values: your town's bye-law decides.
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Searches for the “standard size of stairs for a house” return lists of numbers with no source. This page gives the numbers that two documents actually print, with clause numbers, and says what they do not cover. The Model Building Bye-Laws (MBBL) 2016 are a model prepared for the guidance of States and urban local bodies. They apply to a town only if the town’s own bye-laws are framed on them, so the stair rule that binds your house is the one in your own town’s bye-laws. NBCS 2026 (SP 7:2026, the successor to the National Building Code) describes itself as voluntary and non-binding. For how to find your local rules, see setback rules explained. This page does not give the stair slab thickness or reinforcement: the structural engineer designs those.
What do the model bye-laws say about stair sizes?
Clause 4.17 of the MBBL is the stair clause in the chapter on general building requirements. It has one class for homes, “Residential buildings (dwellings)”, and does not separate a private stair inside a house from a common stair.
| Item | MBBL 2016 (residential buildings) | Clause |
|---|---|---|
| Minimum width of staircase | 1.0 m | 4.17.2 |
| Row housing with 2 storeys | A note gives 0.75; the MBBL print no unit for it | 4.17.2 note |
| Minimum tread, without nosing | 250 mm | 4.17.3 |
| Maximum riser | 190 mm | 4.17.4.1 |
| Risers per flight | “limited to 12 per flight” | 4.17.4.1 |
| Minimum headroom | 2.2 m under a landing, and in any staircase | 4.17.4.2 |
Other buildings have wider stairs, a larger tread and a lower riser: for non-residential buildings the tread is at least 300 mm and the riser at most 150 mm. Those are not for a house.
Clauses 4.17.1 and 4.17.5 refer to “Part 4 ‘Fire and Life Safety’ of NBC 2005”. That edition has been replaced: SP 7:2026 (NBCS 2026) replaced NBC 2016 in 2026. See IS codes for house construction.
What does NBCS 2026 say?
NBCS 2026 has stair clauses in the exit part of its fire and life safety chapter (4.4.2.4.3). It gives its own values, which are not the same as the MBBL’s.
| Item | NBCS 2026 | Clause |
|---|---|---|
| Minimum width, one or two family dwellings | 1.00 m (for row housing with 2 storeys, 0.75 m) | 4.4.2.4.3.2 |
| Minimum tread, residential, without nosing | 250 mm | 4.4.2.4.3.1 |
| Maximum riser, one or two family dwellings | 175 mm | 4.4.2.4.3.1 |
| Risers in a flight | 12 recommended; considering the floor-to-floor height, not more than 15 | 4.4.2.4.3.1 |
| Minimum headroom | 2.2 m under the landing and under the staircase | 4.4.2.4.3.2 |
NBCS words these as “should”, and the MBBL as “shall”. The two documents differ on the riser limit and on the number of risers in a flight, and we state both without reconciling them. The MBBL also differ within themselves: their high-rise chapter (5.4.3) says 15 risers per flight, and their clause on stairs for differently-abled people (8.5) says 12. Ask your authority which rule applies to your house. NBCS also says beams, columns and other building features should not reduce the headroom or the width of a staircase.
NBCS requires a handrail on one side where the stair is under 1.5 m wide, and on both sides at 1.5 m or more, and lets handrails project a small distance into the measured width. We found no handrail height for internal stairs in NBCS. The MBBL give no handrail rule for a house stair in clause 4.17. They print stair handrail heights only elsewhere: in the high-rise chapter (5.4.3) and for fire-escape stairs (11.8), and neither is a rule for a house stair. Clause 4.12 sets a height for parapets and handrails at the edges of terraces, balconies and verandahs, which is a guard at a floor edge and not a stair rule.
What do the model bye-laws not say?
Clause 4.17 of the MBBL has no rule for a landing size in a house, for winders, for the guard or baluster spacing on a house stair, or for lighting a stair. Spiral stairs appear only in the fire-escape section (11.8.1), and stair lighting only in the high-rise and fire chapters. The only landing text is in the fire-exit door rules (clause 4.24), which apply to buildings identified under the fire chapter, so we do not treat it as a house rule. So for these items the drawing, your town’s bye-law and your engineer decide.
How do I check the stair on my plan?
This is practice, not a standard. It is arithmetic and checking, and the limits come from your local bye-law.
- Take the floor-to-floor height from finished floor to finished floor, including the slab and finish thickness.
- Divide it by a trial number of risers to get the riser height. Adjust the number until the riser is within the limit your local rule gives.
- Make all the risers equal, including the first and last. Tile or stone at the bottom and the top changes the finished riser, so the structure is set with the finish in mind.
- A flight has one tread fewer than its risers, because the top of the flight is the upper floor or a landing. The run follows from the tread.
- Check that the plan can hold the run and the landing. If it cannot, change the type of stair: see staircase types for a house.
- Check the headroom against the beam, slab edge or landing above, using finished levels, and allow for plaster or a false ceiling.
- Keep door swings away from the flight, and do not let a door open straight onto a step.
- Plan the light, a handrail on the open side, and the opening in the roof slab if the stair goes up to the terrace. A stair cover over the top of the stair is called a mumty in the MBBL, a structure to enclose only the stairs and protect them from weather, not used for human habitation (definition 82). How it counts in height and area is a local rule.
- Put the stair size on the drawing before the slab is cast. See working drawings for a house for where the stair details go, and how to read a house plan for how a stair is drawn.
What mistakes should I avoid?
These are practice, not code rules.
- Unequal risers because the floor finish was added after the structure was set.
- Short headroom under a beam, landing or slab edge, especially after plaster or a false ceiling.
- A door that swings onto the stair or opens straight onto a step with no landing.
- No handrail on the open side, or wide gaps in the railing.
- A stair too narrow to carry furniture.
- A stair made steeper to save floor space.
- A dark stair, with no light or a switch at one end only.
- Slippery tiles on the tread and the nosing.
- A stair to the terrace with no cover, so rain reaches the door.
- Deciding the stair size after the slab is cast.
- Copying a stair rule from a foreign website or from another town.
Frequently asked questions
What is the standard width of a staircase in a house?
The MBBL 2016 give a minimum of 1.0 m for residential buildings (4.17.2), and NBCS 2026 gives 1.00 m for one or two family dwellings. Your town’s bye-law decides.
What is the maximum riser height for a house?
The MBBL say 190 mm for residential buildings, and NBCS 2026 says 175 mm for one or two family dwellings. They differ, so ask which your town applies.
What is the minimum tread?
Both say 250 mm without nosing for residential buildings.
How many steps can be in one flight?
The MBBL say risers are limited to 12 per flight (4.17.4.1). NBCS recommends 12 and says there should not be more than 15, considering the floor-to-floor height.
What is the minimum headroom of a staircase?
Both give 2.2 m: the MBBL for a passage under the landing and in any staircase, and NBCS under the landing and under the staircase.
Do these rules apply to my house?
Only the rules of your town apply. The MBBL are a model, and NBCS is voluntary. Ask your authority or architect for the stair clause of your bye-laws.
Related guides
- Staircase types for a house: straight, L, U and spiral
- Minimum room sizes, ceiling height and window area for a house
- Working drawings for a house: the full list
This guide is general information. Read the disclaimer. Your architect, structural engineer and local authority decide the stair for your house.
Sources
- Model Building Bye-Laws 2016 (Town and Country Planning Organisation, Ministry of Housing and Urban Affairs): clause 4.17 (4.17.1 to 4.17.5), clause 4.12, definition 82 mumty and clause 5.4.3 (page images read for 4.17, 4.12 and 5.4.3). A model prepared for the guidance of States and urban local bodies; it applies only where adopted.
- SP 7:2026, National Building Construction Standards (NBCS) 2026, Part F Fire and Life Safety, clauses 4.4.2.4.3.1 and 4.4.2.4.3.2 on staircases (page images read). From an unofficial archive.org copy. NBCS describes itself as voluntary and non-binding.
General information only. It is not a structural design or professional advice. Ask a licensed structural engineer or architect to check your plans and site.