Door Frame Sizes in India: Standard Chowkhat Sizes (India 2026) — A homeowner's size chart for door frames (chowkhat) — IS 4021 sections, rebates, modular designations and frame sizes by room.

Dimensioned door frame section showing head, jambs, rebate and overall frame width and height

Get the door frame sizes right and everything downstream falls into place: the leaf fits, the lock lines up, the opening in the wall is the correct size, and the carpenter does not have to pack out or chisel away to make a mismatched leaf shut. In India the door frame is the chowkhat — the timber, WPC, steel or RCC surround that the shutter hangs and shuts against. Its size is described two ways: the section (the cross-sectional dimensions of the timber, e.g. 100x62mm) and the overall frame size (the height and width of the finished surround, which sets the size of the opening you build). This guide gives you the standard size charts used on Indian sites, the IS 4021 sections, the rebate that holds the leaf, the modular ‘M' designations, and how a frame size relates to both the leaf and the structural opening. For the full frame story — materials, joinery, fixing — start at the phase pillar, door frames, or the cluster's complete door guide.

Frame section sizes (the cross-section)

The section is what the timber merchant sells you, by the running foot (rft). For a residential timber chowkhat the two workhorse sections are 100x62mm (roughly 4 inch x 2.5 inch) and the slimmer 75x62mm. The 100mm face is the depth into the wall — it should comfortably exceed the leaf thickness plus the rebate. The 62mm width is the part you see face-on after plastering. IS 4021 (timber door, window and ventilator frames) lays out standard sections; sites round these to the nearest stock size.

Frame section (W x D, mm)	Imperial (approx)	Typical use	Notes
100 x 62	4 x 2.5 inch	Main / heavy internal doors	Workhorse residential section; takes a deep rebate
75 x 62	3 x 2.5 inch	Internal & bathroom doors	Slimmer face, lighter frame
60 x 45	2.4 x 1.8 inch	Light internal / WPC profiles	Common in WPC/uPVC moulded sections
120 x 75	4.7 x 3 inch	Tall / double main doors	Extra depth for double-rebate & weight

The depth (the 62 or 75mm dimension) must match your finished wall: it has to bridge the masonry plus plaster on both faces so the frame sits flush. A 230mm brick wall plastered both sides finishes around 250mm, so the frame is set with the rebate forward and the plaster lapped onto the frame edge. WPC, uPVC and aluminium frames come as fixed extruded profiles rather than cut timber — their section is the manufacturer's, not yours to choose; see door frame profiles.

The rebate — where the leaf shuts

The rebate (also called the check) is the L-shaped recess cut into the frame that the leaf closes into. Two dimensions matter: the rebate depth equals the leaf thickness (so the shut leaf sits flush, not proud), and the rebate width (the lip the leaf shuts against) is typically 12–15mm. A single rebate suits one leaf; a double rebate is used for double doors or for a weatherproof external check. Get the rebate depth wrong and the leaf either stands proud of the frame face or sinks too deep and fouls the architrave.

Leaf thickness	Rebate depth	Rebate width	Common on
30 mm	30 mm	12 mm	Light internal / bathroom leaf
35 mm	35 mm	12–15 mm	Standard flush / panel internal
38–40 mm	38–40 mm	15 mm	Main door / solid leaf

Deeper detail on the geometry lives in door frame rebate; the full parts list (head, jambs, sill, horn, transom) is in door frame anatomy.

Modular size designations (1M = 100mm)

Manufacturers and the modular system describe door openings in ‘M' (module) units, where 1M = 100mm. A door written as 10 x 21 means a 1000 x 2100mm opening (10 modules wide, 21 modules tall). This is the language used in catalogues for flush doors, WPC frames and pre-engineered sets, so it is worth being fluent in it when you order. The modular number usually refers to the opening / frame outer size, with the leaf made slightly smaller to fit inside the rebate.

Modular designation	Size (W x H, mm)	Common application
6 x 20	600 x 2000	Bathroom / toilet
7 x 20	700 x 2000	Small bathroom / store
8 x 21	800 x 2100	Internal bedroom door
9 x 21	900 x 2100	Main internal / single main
10 x 21	1000 x 2100	Main entrance door
12 x 21	1200 x 2100	Wide / double main door

Door frame sizes by room

The door frame sizes you actually build differ by room, balancing furniture movement, wheelchair access and privacy. As a rule of thumb on Indian residential sites:

Door	Frame opening W x H (mm)	Imperial (approx)	Notes
Main entrance	900–1200 x 2100	3–4 x 7 ft	Wider/double for grand entries; heavier section
Internal (bedroom)	750–825 x 2000–2100	2.5–2.75 x 7 ft	825mm helps furniture & accessibility
Bathroom / toilet	600–750 x 1980–2100	2–2.5 x 6.5–7 ft	Use WPC/PVC/RCC frame, not bare timber
Utility / store	600–750 x 2000	2–2.5 x 6.5 ft	Narrow acceptable

For accessibility, the clear opening width matters more than the frame size: RPwD Act 2016 and the Harmonised Guidelines push for an 800–900mm clear leaf on key doors, and frame thickness plus a half-open leaf eat into the clear width — so an 825–900mm frame is the safe minimum on accessible routes. See accessible doors and the broader door size standards. For a quick size pick by room, the door rough opening calculator handles the arithmetic.

How frame size relates to leaf and opening

Three sizes nest inside one another, and confusing them is the commonest measuring error:

1. Structural / rough opening — the hole you build in the masonry. It equals the frame outer size + ~10–12mm packing/grout gap on each side. A 900mm frame therefore needs roughly a 920–924mm rough opening. Always cast a lintel/RCC header over it with 150–200mm bearing each side; see door lintel requirements.

2. Frame outer size — the chowkhat's overall height and width, set to the modular/room size above.

3. Leaf (shutter) size — made smaller than the frame's inner rebate by the working clearances: about 3mm at the head and stiles, with a 6–12mm undercut at the bottom over the finished floor for ventilation and floor-finish changes. Get these margins right in door clearances and tolerances.

So the chain runs: choose the leaf size → add the rebate and clearances to get the frame inner size → add the section to get the frame outer size → add the packing gap to set out the rough opening. Build the opening first and squeeze the frame in afterwards and you will be packing or trimming. For setting it all out on site, walk through measuring for a door and the door rough opening guide. Costs by section and material are covered in door frame cost.

When in doubt, hand the cutting list to a skilled carpenter: a true chowkhat is set plumb, level and square, and small size errors at the frame stage become latch failures and self-swinging leaves later. In bathrooms and ground-contact positions, prefer WPC, PVC, RCC or aluminium frames over untreated timber to beat India's termite and damp realities.

Frequently asked questions

What is the standard door frame size in India?

For a main entrance, a 900–1200 x 2100mm frame opening is standard; internal doors are 750–825 x 2000–2100mm, and bathrooms 600–750 x 1980–2100mm. The timber section is typically 100x62mm or 75x62mm. In modular terms a common main door is 9 x 21 (900 x 2100mm).

What does 100x62 mean for a door frame?

It is the section — the cross-sectional size of the chowkhat timber: 100mm deep (into the wall) and 62mm wide (the visible face). The slimmer alternative is 75x62mm for lighter internal doors. It is sold by the running foot under IS 4021.

What is 1M in door sizing?

1M = 1 module = 100mm. So a door written as 10 x 21 is a 1000 x 2100mm opening. The modular number usually describes the frame/opening size, with the leaf made slightly smaller to fit the rebate.

How much bigger should the wall opening be than the frame?

Leave about 10–12mm packing/grout gap on each side — so a 900mm frame needs roughly a 920–924mm rough opening. That gap lets you set the frame plumb, level and square before grouting or foaming it in.

How does the rebate size affect frame size?

The rebate depth equals the leaf thickness (30–40mm) and the rebate width is 12–15mm. The rebate is cut into the frame's inner face, so a deeper rebate for a thicker leaf needs a frame section deep enough to carry it — which is why heavy main doors use the 100x62 (or deeper) section rather than 75x62.