Replastering a Room: What Actually Happens

Before the plasterer arrives

The room needs to be clear. Plaster splashes, dust travels, and moving furniture mid-job costs time you are paying for. Carpets are usually lifted or fully protected, and anything staying in the room gets sheeted.

This is also the point to finalise anything that lives in the wall: sockets moving, new lighting circuits, a TV point, extractor ducting or a radiator relocating. All of it is cheap now and expensive next week.

Preparation and background

Old plaster comes off where it has failed, and the exposed background is assessed. Different backgrounds need different treatment: engineering brick and dense block need a bonding agent, old lime-plastered walls need a compatible approach, and dusty surfaces need stabilising.

Beads go on at external corners and around openings, and any electrical boxes are set to the correct depth for the finished plaster thickness.

Floating and setting

A backing coat is applied and ruled flat, then allowed to firm up. The finish coat goes on over it in two thin passes and is trowelled several times as it sets, which is the part that produces a flat, polished surface.

A typical room is one to two days of plastering for a skim over sound walls · A full strip and float takes longer and creates significantly more waste · Ceilings usually go first, then walls, so splashes are covered · The plasterer needs power, water and reasonable warmth on site

Drying and decorating

New plaster is dark and wet when finished and gradually turns a uniform pale pink or cream as it dries. Painting before that colour is even traps moisture and causes peeling.

Ventilate rather than blast heat at it. Rapid forced drying causes cracking and can leave the surface hard-set with a soft core.

The first coat should be a thinned mist coat of matt emulsion so it soaks into the surface and provides a key for the full coats.

Frequently asked questions

How long does plaster take to dry before painting?

It depends on thickness, ventilation and temperature. The reliable indicator is colour: the whole surface, including corners and behind radiators, must be a uniform pale shade with no dark patches.

Can you live in the house while a room is being plastered?

Usually yes. Dust is manageable with sheeting and a closed door, but the room itself is out of use, and the drying period afterwards means the door stays open and the heating on.

Do plasterers move furniture and lift carpets?

Some will as part of the price and some expect the room cleared. It should be agreed in writing before the day, because it materially affects the time on site.

Should I skim or fully replaster?

Skim over sound, flat, well-bonded plaster; strip and float where the existing coat is hollow, badly out of plane or salt-contaminated from historic damp.