How we supply it: Wall putty is arranged through a partner paint and hardware dealer who quotes, supplies and bills it and pays us a referral commission. We supply the P-Sand that decides how smooth the plaster is, and that in turn decides how much putty you will need.
In one line: Wall putty is a fine white powder of white cement, polymers and fillers, mixed with water and spread thin over plaster to fill pores and small undulations before primer and paint.
What putty is for
Wall putty is a fine white powder of white cement, polymers and fillers, mixed with water and spread thin over plaster to fill pores and small undulations before primer and paint.
It is a finishing skim, not a plaster. Putty hides texture; it cannot straighten a wavy wall, and thick coats crack.
Putty types on the shelf
| Type | Base | Where | Note |
|---|---|---|---|
| White cement putty (powder) | White cement and polymers | Interior and exterior plastered walls | Resists water once cured |
| Acrylic putty (ready paste) | Acrylic emulsion | Interior walls, touch-ups | Not for damp or exterior walls |
| POP or gypsum finish | Plaster of Paris | Interior ceilings, mouldings | Weak against moisture |
Choosing by wall, not by habit
Ground-floor walls in low-lying plots often carry rising damp. Putty over damp plaster blisters and flakes, whatever the type.
Bathrooms and kitchens see steam daily, and exterior walls take the north-east monsoon head on. Both need a cement-based product.
How much putty you need
Typical estimate: for two coats on new cement plaster: about 10–15 sq ft per kg. Rough plaster sits at the low end.
Good plastering is what saves putty. Well-floated plaster with a fine P-Sand pushes coverage to the top of the range.
- 100 sq ft: 7–10 kg
- One 40 kg bag: 400–600 sq ft
- 12 × 12 ft room, 10 ft high, walls and ceiling less one door and one window (about 584 sq ft): 39–58 kg
Applying two coats
- Let new plaster cure and dry, commonly about four weeks (typical).
- Brush off dust and loose sand; fill cracks wider than a hairline first.
- Mix powder into clean water in the ratio printed on the bag, rest it a few minutes, remix, and use it within the stated pot-life.
- Apply the first coat with a putty blade, as thin as the surface allows.
- When dry, sand lightly and apply the second coat at right angles to the first.
- Sand smooth with fine emery paper, dust off and prime.
Quality checks, bag to wall
- Check the bag says interior, exterior or both, and note the packing date.
- The powder should be white, free-flowing and lump-free.
- Mix a small trial; it should spread without dragging or crumbling.
- Scratch a dry first coat with a fingernail; it should not powder off.
- Hold a tube light low against the finished wall to spot ridges before priming.
Storing putty
- Keep bags raised and covered; cement-based putty absorbs moisture like cement.
- Fold and clip opened bags and use them within a few days.
- Mix only what can be spread within the pot-life; set putty cannot be re-tempered.
Putty mistakes
- Putty on fresh, damp plaster; it blisters and peels within months.
- One thick coat to hide poor plastering.
- No sanding between coats.
- Covering damp patches instead of curing the damp.
- Painting straight over putty without primer, which drinks paint unevenly.