Filling Cracks In Plaster Walls

Expert advice and detailed instructions on repairing the most common plaster wall and ceiling problems including cracks holes and sagging.

Filling cracks in plaster walls. However if the plaster separates from the lath or the structure of the wall it s called blown plaster and it requires a more extensive repair. Mix a batch of plaster and fill the. But plaster walls respond to inevitable foundation shifts and climatic changes and can begin to crack. For finishing you ll need primer and paint.

Treat minor cracks in plaster similar to a drywall crack with joint compound. Plaster repair is much. To repair small cracks in plaster you ll need patching compound medium and fine grit sandpaper a sanding block a putty knife a masonry chisel a paintbrush a rag and a screwdriver. Repairing small cracks in plaster is easy compared to plastering a whole room.

Some like a small hairline crack usually aren t a big deal. Expansion and contraction of the wood studs as they shrink and expand with changing humidity levels can cause the plaster to crack. Plaster applied to wood lath is held in place by the keys that form when it squishes through the lath. How to repair plaster walls 1.

There are a couple of reasons why cracks can form in plaster walls. Drill into the plaster photo by david carmack. Once repaired patch dried apply prime coat over the filled in crack and surface surrounding area. And certain key areas such as above and beside doorways and windows are classic areas of cracking.

No matter what the cause. Whether drywall plaster or concrete walls are susceptible to cracks even walls in newly built homes are prone to cracks which normally occur from settling. Cracks can appear for a number of reasons. Using a 3 16 inch masonry bit drill a hole in the plaster about 2 inches from the crack.

However if the plaster is pulling away from the lath you first need to shore up the wall with a two step process. For more about how plaster walls are built see plaster wall construction over time these. If you are patching a large crack then undercut it remove all the loose plaster and dampen the surface like similar to small crack. Everyday life with its bumps and bangs also takes its toll on plaster walls.

This will hide the repaired area and gives a fine smooth finishing.