Plastering advice
Can Blown Plaster Be Repaired?
Short answer
Blown plaster — plaster that has separated from the wall behind — can normally be repaired by cutting out the loose area, treating any underlying cause such as damp, rebuilding the surface and then skimming. Where large parts of a wall are hollow, replastering the whole wall usually gives a better and longer-lasting result.
How to spot it
Tap the wall lightly with your knuckles. Sound plaster gives a solid, dull sound; blown plaster sounds hollow and may flex slightly. You may also see bulging, fine cracking around the edges of the affected patch, or paint lifting.
Find the cause first
Plaster rarely lets go for no reason. Penetrating or rising damp, a plumbing leak, salts in an old wall or a poor original bond are the usual suspects. Repairing the surface without addressing the cause means the same patch fails again.
Patch or replaster?
Small isolated areas are straightforward to cut out and make good, and skimming the whole wall afterwards keeps the finish even. Where the hollow areas are widespread, taking the wall back and replastering is usually less disruptive overall than repeated patching.
Need this doing?
SJF Plastering covers Sutton, Surrey and South West London. Call 07967 302162 or message us on WhatsApp for a free quotation.