Window Grill Design for Home: Types, Safety and Prices (2026)

A good window grill design for a home is usually the simplest one: plain vertical mild steel bars about 12 mm thick with gaps of 100 mm or less, fixed flush in the window opening, primed and finished with two coats of enamel, and with one leaf in every bedroom that unlocks from inside so it doubles as an escape and rescue route. Box grills, laser-cut panels and stainless steel all have their place, but they cost more and some block that route.

On price, the Central Public Works Department (CPWD) schedules a fixed mild steel grill at about ₹238 per kg, roughly ₹300 per sq ft for a plain design. Online seller listings start far lower.

About the numbers below: schedule rates are from the CPWD Delhi Schedule of Rates 2023, based on Delhi prices of April 2023 and including GST at 18%, so they are indicative only. The online figures are a market range: the middle half of seller asking prices on IndiaMART's iron and aluminium window grill pages, read on 21 Oct 2026. Sellers do not say consistently whether paint, fixing or GST is included. Weights are our arithmetic. Opening and gap sizes come from UK guidance, as we found no Indian rule that sets them for homes. "Our guidance" means common practice, not a code.

Window grill types: box, flush, openable and the rest

Box grill. A cage that projects 300 to 450 mm out from the wall (our guidance), with a sloping top and a ledge. It gives a ledge for flower pots or an AC unit, uses about twice the steel of a flush grill, and a fixed box is the hardest thing for firefighters to get through.

Flush grill. Bars fixed inside the window reveal, outside the glass. The least steel and the cleanest elevation; the usual choice for flats and small windows.

Openable or sliding grill. A fixed grill with one hinged or sliding leaf that locks from inside, for escape, rescue and cleaning. Every bedroom should have one.

Invisible grill. Stainless steel cables across the opening, better suited to balconies; our upcoming guide to balcony design for flats covers them and railing rules.

Jaali-style laser-cut panel. A steel or aluminium sheet cut to a pattern in a frame, giving privacy and shade as well as security. Aluminium grill. Light and rust-free.

Three vertical sections through a 1,200 mm high sliding window in a 230 mm wall, with plans below: a box grill projecting 300 to 450 mm out from the wall with a sloping top and a ledge holding a pot; a flush grill fixed in the outer reveal with lugs into lintel and sill; and an openable grill in the reveal with a lock in reach from inside and a 600 mm leaf hinged at the jamb that swings outward. Each plan shows two glass shutters and a mosquito mesh shutter on the inner track — The three grill types in section and plan. A box grill gives a ledge but blocks rescue unless it has a door; a flush grill uses the least steel; an openable leaf gives an escape and rescue route. Sizes are our guidance. Diagram: MOA

Window grill design simple: patterns that age well

The latest and new model designs online are mostly flowers, scrolls and sunbursts, which date fastest. Designs that age well share four things (our guidance):

Verticals or flat bars, not busy motifs. Flat bars turned edge-on read as a modern screen.
One pattern for the whole house, sized to each opening, rather than a different design at every window.
The frame colour: charcoal or black to match the window frames, or the wall colour so the grill disappears.
Fewer joints, since rust starts at welds and crossings.

Four mild steel grill patterns for the same 1,200 by 1,200 mm window, drawn to scale with weights: plain vertical 12 mm square bars at 100 mm clear gaps, 19 kg or 1.2 kg per sq ft; a 12 mm square grid with 100 mm squares, 33 kg or 2.1 kg per sq ft; 40 by 6 mm flat bars turned edge-on, 31 kg or 2.0 kg per sq ft; and a 3 mm laser-cut sheet in a frame, 29 kg or 1.9 kg per sq ft, with notes on the 100 mm sphere test, climbing and cleaning — Simple patterns compared on one window. Since mild steel grills are priced by the kilo, weight drives cost: plain vertical bars use the least steel and give a child nothing to climb. Weights are our arithmetic from the IS 1786 steel density. Diagram: MOA

Where you want pattern, repeat one. In this Rohtak house front by RAH Architects, a single perforated screen runs up the stair, over the arch and across the gate.

Design render of a white four-storey house front at dusk in Rohtak: a tall perforated geometric screen runs up the centre in front of a double-height glazed stair, an arched screen panel crowns it, black ornamental railings guard the balconies on either side, and a matching perforated gate closes the parking — Design render: one perforated screen pattern is repeated on the stair glazing, the arch and the gate, while the balconies get simple black railings. A repeated pattern like this ages better than a different design at every window. Image: RAH Architects on MOA

Perforated metal can also wrap a whole facade. At the Tree House in Panchkula, Varun Garg Architects used tall bronze-finish panels on the upper floor and the boundary.

Side view of a contemporary Panchkula house: tall bronze-finish perforated metal panels with a leaf-vein pattern clad the upper floor and continue as the boundary screen in the foreground, beside a white cantilevered terrace with a glass railing, potted palms and a Y-shaped timber-finish column — Perforated metal panels screen the upper floor and the boundary of this Panchkula house, giving privacy and shade while letting light and air through. Image: Varun Garg Architects on MOA

Iron, steel or aluminium: which material

Mild steel (MS), the usual "iron" grill. Cheapest, strong and easy to weld into any pattern, but it rusts unless painted. A "wrought iron" grill today is usually mild steel worked into scrolls: mild steel replaced true wrought iron, and many gates and railings sold as wrought iron are mild steel (Wikipedia: Wrought iron).

Stainless steel: SS 304 or SS 316. The International Molybdenum Association, an industry body, says the molybdenum in Type 316 makes it more resistant to chloride salts, including coastal air (IMOA, April 2015). It finds 316 works on typical coastal sites 0.2 to 16 km from the sea where rain washes the surface; closer in, it suggests a grade such as 2205 duplex (IMOA, January 2015). Our guidance: SS 304 inland, SS 316 in coastal cities, with the grade on the quote. See also our guide to building near the sea.

Aluminium. It is light and does not rust, but it is softer, so it suits privacy screens and upper floors better than ground-floor security (our guidance). CPWD lists aluminium grill to IS 1868 as a basic material at ₹294 per kg, before GST and fixing.

Rust protection for MS grills

Asian Paints' guide for gates and grilles says to remove rust, grease and loose paint, never paint damp metal, and apply one red oxide primer coat and two coats of enamel or PU enamel. Near the coast it asks for an anti-corrosive primer and full coverage at welds and corners, where rust often begins (Asian Paints).

Our guidance: prime every piece before fixing, including faces against the wall, touch up chips before each monsoon, and near the sea ask for hot-dip galvanising under the paint.

Bar spacing: child safety and burglar resistance

We found no Indian standard we could open that sets the gap between window grill bars. The UK's guidance on guarding is a useful benchmark: where children under five may be present, no opening should let a 100 mm sphere pass, and horizontal rails should be avoided so children cannot climb (Approved Document K, 2013 edition, para 3.3).

For window grills, our guidance is:

Gaps of 100 mm or less everywhere, including at the frame. That also stops an adult.
No ladder of horizontals on low sills and French windows: keep stiffeners few and high.
Solid bars, about 12 mm square or 16 mm round, rather than thin hollow pipe on ground floors.
Fixings that hold: lugs set in concrete or anchors into RCC, not screws into plaster.
Hinges and locks that cannot be undone from outside: welded hinge pins and a padlock that only a hand from inside can reach.

The fire escape problem with fixed grills

A fixed grill keeps burglars out, and keeps you in and the fire brigade out. After the August 2018 fire at Crystal Tower in Mumbai, where fixed grills made the rescue very difficult, a corporator proposed making removable grills, or grills with a door, mandatory in high-rises. A deputy fire officer told DNA such grills would be "of great help in saving people during an emergency" (DNA, 27 September 2018). We could not confirm whether the proposal was adopted.

The Model Building Bye-Laws 2016 say that in buildings 15 m and taller, and others covered by their fire chapter, external windows shall not be blocked by louvres and the like, so people can be rescued through them with a hydraulic platform (MBBL 2016, section 4.24.3(g) with section 11.1). Grills are not named, but a fixed grill blocks the same route, so our reading is that an openable leaf respects the rule. Ask your local fire office what applies.

For the size of the leaf, the UK's fire guidance for houses asks an escape window for an unobstructed opening of at least 0.33 sq m, at least 450 mm high and 450 mm wide, with the bottom no more than 1,100 mm above the floor; locks are allowed (Approved Document B, Volume 1, 2019 edition with amendments to 2026, para 2.10). It relies on escape windows only for floors up to 4.5 m above the ground. Higher up, the leaf is for firefighters to reach you and for smoke to escape, not for jumping.

Scaled elevation from outside of a 1,500 by 1,200 mm bedroom window with a 900 mm sill: a mild steel grill of vertical bars at 100 mm clear gaps with one mid-height stiffener, and a shaded 600 by 1,200 mm leaf on the right hinged on the outer jamb with a padlock on its free edge. Six numbered notes explain the leaf size, the 1,100 mm maximum sill height and 450 by 450 mm minimum opening from UK Approved Document B, the inside lock with a key on a hook, outward-swinging hinges, the 100 mm sphere rule from Approved Document K, and a mosquito mesh that slides away — An openable escape leaf in a bedroom window grill. Opening sizes are from the UK's Approved Document B, used for reference because we found no Indian rule we could open that sizes a home escape window; the rest is our guidance. Diagram: MOA

Mosquito mesh with a window grill

The mesh has to move with the escape leaf, or the route is blocked again. Three ways that work (our guidance):

A mesh shutter on the third track of a sliding window, inside the glass. The neatest option for new windows.
A hinged or pleated mesh frame inside a casement window, which opens with the window.
Mesh fixed to the grill outside, on fixed parts only. Hard to clean.

CPWD prices fly-proof wire gauze with 1.4 mm apertures, fixed with MS flats, at ₹844.70 per sq m (about ₹78 per sq ft) in galvanised steel and ₹1,133.55 per sq m (about ₹105 per sq ft) in SS 304 (DSR 2023, items 10.29.1 and 10.29.2). Near the sea, stainless mesh lasts longer.

Window grill design for small windows and small houses

Kitchen and bathroom windows are usually too small to escape through, so a fixed flush grill is fine; leave a cut-out for the exhaust fan.
Staircase windows in apartment buildings are part of the escape route, so do not grill them shut without checking the building's fire approval (our guidance).
uPVC and aluminium sliding windows: fix the grill into the wall reveal, not into the window profile (our guidance).
Small houses on tight plots: a flush grill keeps the side setback clear; a box grill projects into it. Our guide to building materials by climate helps with finishes.

Breeze-block jaali is another option where you want light and air more than an openable window, as on the balconies of this Vijayawada house.

Design render of a Vijayawada house front: grey jaali blocks with a faceted pattern form the balcony parapets and a full-height vertical strip, set against terracotta cladding, white walls and large curtained windows in deep grey frames — Design render: jaali blocks guard the balconies and screen a full-height strip of this Vijayawada house, a masonry alternative to a metal grill where light and air matter more than an openable panel. Image: Sandilya Chowdary on MOA

Window grill price per sq ft and per kg

MS grills are priced by weight, so pattern and bar size drive the cost. CPWD's Delhi Schedule of Rates 2023 gives:

MS grills of any pattern, in flats, square or round bars, with a coat of steel primer: ₹238.35 per kg fixed into openings or wooden frames with rawl plugs and screws, and ₹219.10 per kg welded to steel windows (items 9.48.2 and 9.48.1).
Red oxide zinc chromate primer on steel work ₹67.40 per sq m, and synthetic enamel, two or more coats, ₹155.90 per sq m (items 13.50.3 and 13.61.1).
Stainless steel (grade 304) railing work ₹772.40 per kg (item 10.28), against ₹172.60 per kg for MS railings and guard bars (item 10.25.2). That puts stainless at roughly four to five times the cost of MS by weight, by our arithmetic.

On IndiaMART's iron window grill page, the middle half of 14 per-kg listings ran from ₹85 to ₹130 per kg, and the middle half of 14 per-sq-ft listings from about ₹140 to ₹460 per sq ft. Aluminium listings ran from about ₹27 to ₹900 per sq ft, too mixed to be useful, and we could not load the steel grill pages.

A 4 x 4 ft window (1,200 x 1,200 mm)	Steel	At CPWD rate	At IndiaMART ₹85 to ₹130 per kg
Flush grill, plain vertical bars	about 19 kg	about ₹4,600 (₹295 per sq ft)	₹1,600 to ₹2,500
Square grid or flat bars	31 to 33 kg	₹7,300 to ₹7,800	₹2,600 to ₹4,300
Box grill, 450 mm deep	about 39 kg	about ₹9,300	₹3,300 to ₹5,100

Weights are our arithmetic from the drawing above. The CPWD figure includes fixing, primer and GST at Delhi's 2023 prices but not the enamel; the seller figures may include none of these. Add hinges and a lock for an openable leaf, and ask each fabricator to quote bar size, weight and inclusions. Grill details belong in the drawing set your architect hands over. For the whole build, try MOA's free home cost calculator.

FAQ

What is the standard size of window grill bars?

We found no Indian standard for home grills. A sturdy choice is 12 mm square or 16 mm round solid bars in a 25 x 6 mm frame, gaps of 100 mm or less (our guidance).

Which is better for window grills, iron or steel?

Painted mild steel is cheapest but needs repainting. Stainless steel costs four to five times as much per kg on CPWD's rates and needs no paint; choose SS 316 near the sea.

What is the window grill price per sq ft?

About ₹300 per sq ft for a plain fixed grill at CPWD's 2023 Delhi rate, more for box and laser-cut designs. IndiaMART sellers mostly asked ₹140 to ₹460 per sq ft, or ₹85 to ₹130 per kg.

Should window grills open for fire safety?

Yes, at least one leaf in every bedroom, locked from inside with the key kept beside it. A Mumbai deputy fire officer has said openable grills would help rescues, and the Model Building Bye-Laws ask that windows in high-rises are not blocked to rescue.

What grill suits a sliding or uPVC window?

A flush grill fixed into the wall reveal outside the glass, with the mosquito mesh on the inner track, and one leaf that opens outward.

Planning windows, grills and a facade that work together? Find architects on MOA and filter the directory by your city.

Sources

Central Public Works Department: Delhi Schedule of Rates 2023, Volume 1 (items 9.48, 10.25, 10.28, 10.29 and basic rate 8774) and Volume 2 (items 13.50 and 13.61) (accessed 21 Oct 2026)
Ministry of Housing and Urban Affairs / TCPO: Model Building Bye-Laws 2016, mohua.gov.in (accessed 21 Oct 2026)
UK Government: Approved Document K, Protection from falling, collision and impact, 2013 edition, gov.uk (accessed 21 Oct 2026)
UK Government: Approved Document B, Fire safety, Volume 1: Dwellings, 2019 edition incorporating amendments to 2026, gov.uk (accessed 21 Oct 2026)
DNA: Mumbai: BMC proposes removable grill in high-rise buildings, 27 September 2018, dnaindia.com (accessed 21 Oct 2026)
Bureau of Indian Standards: IS 1786:2008, High strength deformed steel bars, clause 7.2.1 (density of steel), law.resource.org (accessed 21 Oct 2026)
International Molybdenum Association: Austenitic stainless steels, April 2015, imoa.info (accessed 21 Oct 2026)
International Molybdenum Association: Assessing the corrosiveness of coastal environments, January 2015, imoa.info (accessed 21 Oct 2026)
Asian Paints: Metal paint buying guide for gates, grilles and railings, asianpaints.com (accessed 21 Oct 2026)
Wikipedia: Wrought iron, en.wikipedia.org (accessed 21 Oct 2026)
IndiaMART: Iron window grill, indiamart.com (accessed 21 Oct 2026)
IndiaMART: Aluminium window grill, indiamart.com (accessed 21 Oct 2026)