Gypsum plaster goes on in one coat, sets in minutes, needs no water curing and gives a smooth white surface. Sand-cement plaster needs water curing for several days and usually a finishing coat before paint.
| Gypsum plaster | Sand-cement plaster | |
|---|---|---|
| Water curing | None | Several days |
| Setting | Minutes (IS 2547: 10 to 30) | Hours, then days to gain strength |
| Coats | One coat, 6 to 20 mm | One or two coats, then often a finishing coat |
| Surface | Smooth and white, ready for paint work | Grey and rougher |
| Load on the building | Less | More |
| Where | Inside walls and ceilings | Inside and outside |
| Supply | Ready in the bag: add water | Sand, cement and water are mixed on site |
Because there is no curing wait, the next trade can start sooner.