Delhi Room and Stair Rules Under UBBL 2016

The requirement

In Delhi, room size and stair width follow the size of the flat. Up to 50 m², a habitable room needs 7.5 m² of floor and 2.1 m of width. Above 50 m², it needs 9.5 m² and 2.4 m. Height is 2.75 m either way (UBBL 2016, Table 7.1).

Delhi does not just take the national numbers. It has its own rule book, the Unified Building Bye-Laws 2016. The DDA notified it on 22 March 2016. The central government approved it first. A habitable room is a room you live in, such as a bedroom or a sitting room.

Small flat, up to 50 m². The room must be 7.5 m² or more. It must be 2.1 m wide or more. Floor to ceiling, it must reach 2.75 m.

Bigger flat, above 50 m². The room must be 9.5 m², and 2.4 m wide. Height stays at 2.75 m. Where the flat has two such rooms, the second one need only reach 7.5 m².

Two notes sit under the same table. Keep 2.4 m clear under any beam. And no part of the building may go past 4.8 m from floor level to the soffit of the ceiling. There is a way round that second one. Your architect may ask for a double height space. It is not counted twice in the FAR. The height limit for the whole building still holds.

Light and air. The openings in a room, doors left out, must add up to a tenth of the floor area. No part of a room counts as lit if it sits more than 7.50 m from the opening. An inner court that serves such a room must be at least 3.0 m by 3.0 m in a building under 15 m tall. It need not be that big if the space is ventilated by machine.

Stairs in a low-rise home. Low rise means under 15 m tall. The same two bands set the stair width. Up to 50 m², it is 0.9 m. Above 50 m², it is 1.0 m (Table 7.1, item 12).

There is a break for old work. Say you add a floor to an old low-rise home. Say its stair was built 900 mm wide under the 1983 bye-laws. You may keep 900 mm on the new upper floors.

Steps. An inside stair in a low-rise home needs a tread of at least 25 cm, the nosing left out. Other buildings need 30 cm, high-rise flats included. Winders are allowed in a low-rise home. They must not sit at the top of a downward flight. Keep to 12 risers in one flight. Leave 2.2 m of headroom under the stair and under any landing.

Other work is not the same. Flats, hostels, group housing and guest houses need a 1.5 m stair. Halls, cinemas and other assembly buildings need 2.0 m. So do hospitals and the like (clause 7.11.1). A hall for fewer than 150 people may drop to 1.5 m. That note was added on 24 February 2021. Schools need 1.5 m. Once a school stands over 30 m tall, it needs 2.0 m (Table 8.1).

Handrails. UBBL sets the top of the main rail 900 mm above the pitch line of the stair. The same height works on a ramp or a landing. A second, lower rail sits at 760 mm, with a small gap between the two. Fit rails on both sides. Run them without a break, landings included. Carry them 300 mm past the first and last nosing. Keep them 50 mm clear of the wall. A round rail is 38 mm across. The rail and its fixings must hold a 1.7 kN push.

Parapets. At the edge of a roof terrace or balcony, the parapet must be at least 1.0 m high. It must be no more than 1.5 m high. That rule does not bite where no stair reaches the terrace. From 24 m up, the figure is 1.5 m (clause 7.22).

Risers. A riser may be up to 190 mm in a low-rise home. Every other building gets 150 mm, high-rise flats included. On completion, 5 mm either way is allowed. That is clause 7.11(g), as changed by the DDA on 24 February 2021.

Spiral stairs. The same 2021 change lets a spiral stair serve a building up to 15 m tall. It was 9 m before. The stair must now be at least 2 m across, up from 1.5 m.

Later changes. The DDA book we read holds changes only up to 12 February 2020. Two more came after it. One is dated 24 February 2021 and one 29 June that same year. Neither moves the room sizes, the low-rise stair widths, the treads, the headroom, the handrails or the parapets on this page. The first of the two gives the riser and spiral stair figures above.

The national picture has moved. BIS has withdrawn NBC 2016, which it sold as SP 7:2016. SP 7:2026 now takes its place. UBBL points at the latest version of the national code, not a fixed year. We could not confirm the current national figures, so we have not printed them. BIS published SP 7:2026 on 30 April 2026. It withdrew SP 7:2016 the same day.

Related

• Delhi’s building code hub covers the rest of Delhi’s own rules.
• Indian room height and area rules is the national room page.
• Indian stair rules is the national stair page.
• India’s building code hub shows how a model code becomes law in your state.

Sources

• Unified Building Bye-Laws for Delhi 2016 (DDA) — notified vide S.O. 1191(E) dated 22.03.2016 by the Delhi Development Authority under section 57(1) of the Delhi Development Act 1957, with the prior approval of the Central Government (Chapter 1, clauses 1.0–1.2). Clause 1.4.60 defines a high-rise building as 15 m and above, so “low rise” below that. Clause 7.1.3 and Table 7.1 give the graded habitable-room area, width and height, and the low-rise staircase width (item 12); Notes 1 and 2 give the 2.4 m clear headway under a beam and the 4.8 m maximum floor-to-soffit height, Note 2 adding that double height above 4.8 m may be permitted without counting twice in FAR, subject to the overall permissible height of the building; the footnote to the Notes allows a 900 mm stair width built under the 1983 Building Bye-Laws to be retained on added upper floors. Clause 7.11(f) gives the 25 cm / 30 cm minimum tread and the winder allowance, 7.11(g) the 12-riser limit and 7.11(i) the 2.2 m headroom. Clause 7.11.1 (read with Table 8.1 at clause 8.4.3(c)) gives the 1.5 m width for other residential buildings and 2.0 m for assembly and institutional buildings; educational buildings take 1.5 m up to 30 m in height and 2.0 m above it. Clauses 7.20.1 and 7.20.2 give the one-tenth opening area, the 7.50 m daylight limit and the 3.0 m x 3.0 m internal courtyard, the courtyard dimension applying unless the space is mechanically ventilated. Clause 7.22 gives parapet heights. Clauses 11.5.3 and 11.5.3.1 give handrail heights, continuity, extensions, clearances, section and the 1.7 kN load. See the DDA compendium PDF.
• Later amendments to UBBL 2016 — the DDA compendium linked above is consolidated only to 12 February 2020. Two Gazette of India notifications have followed it, both listed at dda.gov.in/building-laws: S.O. 886(E) dated 24.02.2021 and S.O. 2615(E) dated 29.06.2021. S.O. 886(E) replaces clause 7.11(g) with a maximum riser of 190 mm in low rise residential buildings and 150 mm in other buildings including high rise residential, keeps the 12-riser limit per flight and allows a ±5 mm deviation at completion (Annexure IV, (B) ii); it also raises the spiral stair limits in clause 7.11 from 9 m to 15 m of building height and from 1.5 m to 2 m minimum diameter, and adds a note to Table 8.1 allowing 1.50 m for assembly occupancy with fewer than 150 persons. S.O. 2615(E) amends only clauses 2.0.1 and 7.17.2. Neither notification changes Table 7.1, 7.11.1, 7.20, 7.22 or 11.5.3, so the room sizes, low-rise stair widths, treads, headroom, handrails, daylight and parapet figures on this page are current. Kitchen sizes, store-room sizes and corridor and passage widths are outside the scope of this page.
• SP 7:2026, National Building Construction Standards 2026 (BIS) — supersedes SP 7:2016, the National Building Code of India 2016, whose status is now withdrawn (technical committee CED 46). See the BIS standard record for SP 7:2026. The BIS record gives 30 April 2026 as the publication date for SP 7:2026 and the same date as the withdrawal date for SP 7:2016. The full text is sold by BIS, so no national room or stair figures are reproduced here. UBBL 2016, clause 7.20.2 refers to the latest version of the National Building Code at the time of enforcement, rather than to a fixed edition.