Many older homes in Winnipeg still have their original plaster walls and ceilings. Plaster is solid, quiet and hard-wearing, but after decades of seasonal movement, settling and the odd leak, cracks and loose patches are common. The good news is that most damaged plaster can be repaired rather than torn out.
Here is how to read the damage on your walls, what a proper repair involves, and when a section is better rebuilt.
Plaster or drywall? Start by knowing what you have
Plaster in older homes is usually applied in layers over wood or metal lath, or directly over masonry. It is thicker and harder than drywall and sounds dense when you tap it. Drywall is a thinner gypsum board with taped seams, and it sounds hollower between the studs.
The difference matters because the two are repaired differently. A drywall patch on a plaster wall rarely sits flush and often shows through paint. If you are not sure what you have, a few clear photos are usually enough for a contractor to tell.
Common types of plaster damage
Hairline cracks
Fine cracks, especially at corners and above doors and windows, usually come from normal seasonal movement and settling. They are mostly cosmetic, but a dab of filler and a coat of paint tends to last a season before the crack shows again. A lasting repair opens the crack, reinforces it and fills it so it stays closed.
Loose or hollow plaster
Plaster is held to the lath by keys, the bits that pushed through the gaps in the lath when the plaster was applied. Over time some of those keys break. You may notice a section that bulges, feels spongy or sounds hollow when tapped. Loose plaster can often be secured and rebuilt, but if it is left alone it can eventually come away from the wall.
Water damage
Stains, softness or crumbling usually point to a leak from a roof, window or plumbing above. The leak needs to be fixed first. After that, the damaged plaster is cut back to sound material and rebuilt to match the surrounding wall.
Ceiling cracks and sagging
Ceiling plaster carries its own weight, so cracks and sagging deserve attention sooner rather than later. A sagging section is a sign that the plaster is separating from the lath above it.
Repair or replace?
In most cases, cracked or damaged plaster can be repaired. Repair usually makes sense when:
- the damage is limited to cracks, holes or small loose areas
- most of the wall is still firmly attached
- you want to keep original details like curved corners and trim
Rebuilding or replacing a section is usually the better option when:
- large areas have come away from the lath
- the plaster is soft or crumbling from repeated water damage
- the room is being gutted for other work anyway
An on-site look is the best way to decide, because the condition behind the surface matters as much as what you can see.
What a proper plaster repair involves
A good repair is more than filling and painting. It typically means:
- Protecting floors and furniture and containing dust
- Removing loose material back to sound plaster
- Re-securing or rebuilding the damaged area
- Floating new coats so the repair sits flush with the surrounding wall
- Finishing the surface smooth and ready for primer
When it is done well, you should not be able to pick out the repair once the wall is painted.
Can I repair plaster myself?
Small hairline cracks and nail holes are manageable for a handy homeowner. Larger cracks, loose sections, water damage and ceiling repairs are harder to get right, and a patch that does not bond properly will show through paint or crack again. Paint and plaster in older homes can also contain lead or asbestos, so it is worth having them tested before you sand or cut into them.
Plaster repair in Winnipeg
Griffith Plaster has been working on walls and ceilings in Winnipeg homes since 2017. Owner Brandan Griffith is on most jobs himself, and we are licensed, bonded and insured. If your plaster is cracked, loose or water-damaged, see our plaster repair services. If your walls turn out to be drywall, our drywall repair page covers that instead.
Send a few photos and rough dimensions through our quote form or call (204) 806-9810, and we will tell you what the repair involves.