Plastering in Gauteng

No — plaster over damp fails within months. The moisture source (rising damp, leaking gutter, condensation) must be fixed first, then damaged plaster cut back and replaced, sometimes with a salt-resistant renovation plaster. Any plasterer who skips the cause is selling you a repeat job.

Plastering is usually priced per square metre or per room. A skim coat over existing sound walls is the cheapest job; full re-plastering (hacking off old plaster and applying new base and finish coats) costs two to three times more, and exterior rendering is priced separately.

Skimming is a thin 2-3 mm finish coat applied over existing plaster or plasterboard to give a smooth paintable surface. Full plastering means building up base (browning/bonding) coats plus a finish coat, needed when old plaster is blown, damp-damaged or removed back to brick.

A skim coat is touch-dry in a day but needs roughly a week to fully dry before painting; full re-plaster can take several weeks depending on thickness, ventilation and season. Paint too early and you trap moisture, causing peeling. Use a mist coat (diluted emulsion) first.

Yes, if the substrate is sound — plasterers key the surface and use bonding agents. But blown (hollow-sounding), crumbling, or damp-stained plaster must come off first. A good plasterer taps the walls during the quote to check; be wary of anyone who doesn't.

Classic rising damp — older homes with failed or missing damp-proof courses wick ground moisture up the brickwork, and salts push the plaster off. Re-plastering alone fails; you need a DPC repair or injection first, then salt-resistant plaster.