The framing specification, which nobody reads and everybody should
| Component | Specification | Centres | Why it matters |
|---|---|---|---|
| Perimeter channel | 0.5 mm GI, 20 × 27 mm | Fixed at 600 mm to wall | Defines the level; a sagging ceiling often starts here |
| Soffit cleat / hanger | Galvanised, with adjustable rod | 900 – 1,200 mm | Longer spacing is the main cause of visible sag |
| Intermediate channel | 0.9 mm GI, 15 × 45 mm | 1,220 mm | Carries the ceiling sections |
| Ceiling section | 0.5 mm GI, 51 × 26 mm | 450 mm | 600 mm centres will telegraph the board joints |
| Board | 12.5 mm gypsum, tapered edge | — | Tapered edges are what allow a flush taped joint |
| Screws | 25 mm drywall, black phosphated | 200 mm on sections | Over-driven screws break the paper and pop later |
Ask to photograph the grid before boarding. It is the only chance you will get to see it.
Board types and 2026 Mumbai rates
| Board | Where it goes | Rate (₹/sq ft, complete to putty) |
|---|---|---|
| Standard 12.5 mm gypsum | Bedrooms, living rooms, offices | ₹75 – 105 |
| Moisture-resistant (green) board | Bathrooms, kitchen periphery, utility | ₹95 – 130 |
| Fire-rated board | Commercial fit-outs to landlord specification | ₹115 – 160 |
| Perforated acoustic board | Meeting rooms, home theatres | ₹180 – 320 |
| Curved / double-curvature work | Coves, bulkheads, circular features | ₹140 – 240 |
| Peripheral cove with profile lighting slot | Perimeter detail | ₹220 – 400 per running foot |
Painting adds ₹25–45 per sq ft. A 600 sq ft flat with a peripheral cove typically totals ₹70,000–1,10,000 including paint.
Service coordination: the sequence that avoids rework
- Mark the ceiling level after the flooring level is fixed, not before. A 15 mm error in the floor becomes a visible taper in the cove.
- Run all electrical conduits, AC drain lines, refrigerant piping and ducting before the grid goes in, and pressure-test the refrigerant lines before boarding.
- Set out downlight positions on the grid so no light lands on a ceiling section. Cutting a 90 mm hole through a steel section on site is how ceilings get damaged.
- Provide access panels at every AC indoor unit, every drain trap and every junction box. A ceiling with no access is a ceiling that will be cut open within three years.
- Board, tape, three-coat joint, sand, then two coats of putty. Only then paint.
Mumbai: the leak from above
The most common reason we are called to a gypsum ceiling in Mumbai has nothing to do with the ceiling. It is water from the flat above — a failed bathroom waterproofing layer, a leaking drain stack, a chajja that ponds.
- Gypsum absorbs water and loses strength. A board that has been soaked will sag permanently and must be cut out, even after it dries.
- The tell-tale is a brown-edged stain that grows over days. Do not repaint it; find the source first, because paint over a live leak simply moves the stain.
- In a bathroom below another bathroom, use moisture-resistant board and leave a generous access panel. The cost of one panel is trivial against cutting a finished ceiling.
- During monsoon, the top-floor flat is the high-risk one: terrace waterproofing failures show up in the ceiling first. We check the terrace condition before quoting a top-floor ceiling.
- Humidity alone does not damage a gypsum ceiling. Liquid water does.
Care, life and BOQ wording
- No care required beyond repainting every five to seven years. Do not hang anything from the board — fix into the grid or into the slab above.
- Expected life: 15–20 years, and longer if it never gets wet.
- BOQ: “False ceiling in 12.5 mm tapered-edge gypsum board on GI framing — perimeter channel, intermediate channels at 1,220 mm, ceiling sections at 450 mm, soffit hangers at 900 mm; joints taped and three-coat jointed; two coats putty, sanded.”
- BOQ: “Moisture-resistant board in all bathrooms, utility and within 600 mm of the kitchen ceiling boundary.”
- BOQ: “Access panels of 450 × 450 mm minimum at every AC indoor unit, drain trap and electrical junction box, positions per reflected ceiling plan.”
Specification summary
| Property | Specification |
|---|---|
| Board | 12.5 mm tapered edge; moisture-resistant in wet areas |
| Ceiling sections | 450 mm centres |
| Intermediate channels | 1,220 mm centres |
| Hangers | 900 mm centres, adjustable |
| Jointing | Tape plus three coats, sanded |
| Rate | ₹75 – 160 per sq ft to putty, ex-GST |
| Access | Panels at every serviceable element |
| Life | 15 – 20 years absent water ingress |
Frequently asked questions
How much does a gypsum ceiling cost for a 2BHK?+
A 650 sq ft 2BHK with peripheral coves in the living room and bedrooms, and a full ceiling in the passage, typically comes to ₹70,000–1,10,000 including painting, at ₹75–160 per sq ft of ceiling area. Full ceilings throughout rather than peripheral coves roughly doubles the area and the cost.
Why is my gypsum ceiling cracking at the joints?+
Almost always two-coat jointing instead of three, or a framing grid at 600 mm instead of 450 mm. Both let the board edges move slightly against each other and the paint film cracks along the tape line. It is a workmanship defect, and it recurs if it is only filled and repainted.
Can gypsum be used in a bathroom ceiling?+
Yes, with moisture-resistant board and adequate ventilation. It handles humidity and steam. What it does not handle is liquid water from a leak above, so leave an access panel and keep the exhaust fan working.
Gypsum or POP — which should I choose?+
Gypsum for flat ceilings, clean lines and speed; POP for curved and moulded work, and where the budget is tight. Gypsum is a dry system that finishes in days; POP is wet, messy and slower to dry in a Mumbai monsoon. Our gypsum versus POP page compares them properly.
How much ceiling height do I lose?+
Typically 100–150 mm for a flat ceiling with recessed lights, and 200–250 mm where an AC indoor unit or ducting sits above. In a Mumbai flat with a 9 ft 6 in slab height, a peripheral cove that drops only at the edges is usually the better answer than a full ceiling.