The two types
| Type | Base | Rate / sq ft | Use |
|---|---|---|---|
| White cement putty | Cement + polymer | ₹18–28 | The Indian default, internal and external |
| Acrylic putty | Acrylic emulsion | ₹26–42 | Internal only; finer finish, flexible |
| Gypsum-based skim | Gypsum | ₹22–38 | Over gypsum board; fast, dry trade |
| POP punning (alternative) | Plaster of Paris | ₹28–45 | Thicker correction, up to 12 mm |
How many coats, and why sanding matters
Two coats is standard: the first fills, the second levels. Each is sanded, and the sanding is where the quality is decided — an unsanded second coat leaves trowel ridges that a grazing light will find for as long as the wall exists. Three coats is worth it where a wall will be washed by cove lighting or a profile, because the light is deliberately designed to reveal the surface.
Putty, primer, plaster: three different jobs
- Plaster is the cement rendering that builds the wall's surface — 12 mm or more.
- Putty is the thin filler that levels that surface — 1–2 mm across two coats.
- Primer is the sealing coat that bonds paint to putty and stops the putty absorbing the topcoat unevenly.
- Skipping the primer is the single most common cause of patchy emulsion, because putty is porous and drinks the first coat of paint at different rates across the wall.
For quantity: a 40 kg bag of white cement putty covers roughly 400–500 sq ft in two coats on a smooth plaster, less on a rough one. A 1,000 sq ft flat with 3,200 sq ft of wall and ceiling therefore needs seven to eight bags, which is a useful cross-check against a quoted material figure.
When to skip it
Putty is not always needed. Over a well-finished gypsum board ceiling, jointing compound plus primer is enough. On a textured or texture-painted wall, putty is wasted because the texture hides the undulation anyway. And behind full-height joinery or wallpaper, one coat is sufficient — though the wall still needs to be sound and sealed. See our paint guide and the painting cost calculator.
Frequently asked questions
Is wall putty necessary before painting?+
On cement plaster, yes — it is what makes the wall flat and the paint even. On a well-finished gypsum board surface, jointing compound and primer are usually enough. Behind wallpaper or joinery, one coat suffices.
How many coats of putty are needed?+
Two, each sanded. A third is justified where a wall will be grazed by cove or profile lighting, which reveals every undulation. More than three usually means the plaster underneath should have been corrected instead.
What is the difference between putty and primer?+
Putty fills and levels; primer seals and bonds. They are not alternatives. Painting directly onto putty without primer gives patchy coverage because the porous putty absorbs the first coat unevenly.
Can putty be applied in the monsoon?+
It can, but drying stretches from one day to three or four and trapped moisture causes blistering later. If a repaint has to happen in July, allow extra days between coats and check with a moisture meter before priming.