Can plaster walls be repaired, or do they need to be replaced?
E&R Construction · Published October 15, 2026
The short answer
Most plaster walls can be repaired. Hairline cracks and small holes are patched and blended in, and larger damaged areas can be rebuilt. Full replacement is only needed when the plaster is coming away from the wall over large areas.
Plaster is common in older Ottawa homes. It is harder and denser than drywall, and it is usually worth keeping.
Hairline cracks
Fine cracks are normal as a house settles. They are opened slightly, filled and sanded smooth so they disappear under paint.
Holes and damaged patches
Small holes are filled. Larger holes, such as those left after plumbing or wiring work, are built up in layers or patched with a piece of drywall set flush with the surrounding plaster.
Sagging or loose plaster
Plaster is held on by the lath behind it. If an area bulges or sounds hollow when tapped, it has come loose. Small areas can often be re-attached; large areas may need to be removed and rebuilt, or replaced with drywall.
Before anyone sands or cuts
Older plaster and some textured finishes can contain asbestos. If your home is older, have the material tested before anyone sands, cuts or demolishes it.
Plaster or drywall for the repair?
Both can work. Matching plaster keeps the wall consistent; drywall patches are faster for larger areas. The right choice depends on the size and location of the damage.
See our plaster and painting pages, or request a quote.