Repairing Plaster Ceiling Cracks

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Repairing plaster ceiling cracks.

To repair a crack in a ceiling. Besides the normal wear and tear of living plaster and lath ceilings are at the mercy of gravity and they can take only so many water leaks and structural movements before they pull away from the framing. Here tom silva shows how to repair plaster walls to make them look as good as new. Expert advice and detailed instructions on repairing the most common plaster wall and ceiling problems including cracks holes and sagging.

For more about how plaster walls are built see plaster wall construction over time these. Otherwise the cracks come back no matter how many times you patch over them. No matter what the cause you can repair the plaster cracks by using drywall tape and joint compound. Be sure to drive screws into wood lath above.

In this video this old house general contractor tom silva explains how to repair a plaster ceiling. Step 1 remove any loose plaster that s embedded in the crack. Typically plaster ceiling cracks have two causes. House settling and temperature or moisture fluctuations in an attic which result in the expansion or contraction of framing members.

For larger cracks you may need two coats of spackle because of its tendency to shrink as it dries in large gaps so double check before priming and painting. 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. If the plaster ceiling feels firmly attached to the lath then you can do the same repair as for the small cracks above. For finishing you ll need primer and paint.

Plaster applied to wood lath is held in place by the keys that form when it squishes through the lath. If it s a small hairline crack you won t have to worry about this but larger deeper cracks will have debris in them. The key to any fix is to reunite the plaster with the strips of wood lath underneath. A ceiling crack is not an uncommon sight in older homes.

An overview photo by david carmack. Screw plaster washers to ceiling along and around cracked area. What old house owner doesn t have a cracking or sagging plaster ceiling in need of repair somewhere. Repairing small cracks in plaster is easy compared to plastering a whole room.