How to Repair Loose Plaster

LESLIE: Now we’ve got Scott in Iowa on the line who needs help with loose plaster in a painting project. Tell us what you’re working on.

SCOTT: I just recently bought a rental house and the plaster – it’s an older home and the plaster was falling off the house. Well, the guy I bought it from had repaired it but if you look at it, it’s falling out in some areas and bowing back in in some areas. And I was just wondering, would I have to re-drywall it or is there a cheaper and easier way to fix that?

TOM: How much of this exists? Is there a lot of this that’s where there’s loose plaster?

SCOTT: Throughout the whole house.

TOM: Yeah, OK. So loose plaster is a problem because it’s going to be dangerous.

What happens is the plaster, when it’s applied, it’s applied over something called wood lath, which are like thin strips of wood. Kind of looks like those sticks we use to hold up garden plants and tomatoes and things like that. And the plaster expands to behind the lath and it sort of locks in place.

But over the years, with an old house, those keyways, we call them, loosen up and then the plaster is not attached to the wall anymore. So you are looking at a situation where the walls are going to get worse. It’s not going to get better. And if it’s the ceiling that’s loose, it could be dangerous. Because when that plaster falls, it’s really, really heavy. I’ve seen it dent floors and certainly could hurt somebody.

So now we have – the question is: what’s the best way to deal with this? “Should I tear the plaster out? Should I drywall over?” I’ve done it both ways and I’ve come to the conclusion, after trying it this way for many years, that the best thing to do is to put drywall on top of the plaster, not tear it out, for a couple of reasons. First of all, it’s less messy. Secondly, that even when you tear out the lath and the plaster, you’ll find that the studs from the old house behind it are not very even. So when you put drywall up, it tends to warp sometimes.

So what I would do is I would attach new drywall over the plaster. You can use 3/8-inch-thick drywall, too; you don’t even need to use ½-inch drywall. And then by attaching from the drywall, through the plaster into the studs, you’ll help secure that loose plaster so you won’t have any further movement in that room. That would be my recommendation.

SCOTT: That works out.

TOM: Alright. Good luck with that project. Thanks so much for calling us at 888-MONEY-PIT, 888-666-3974.