How to Fix Damaged Plaster
Visitors to thisoldhouse.com asked for help with dinged, gouged, and cracked walls. Here's an easy way to get a smooth surface that lasts
You just gotta love plaster. That rock-hard substance, which was applied to the walls and ceilings of nearly every house in this country until the 1950s, gives us surfaces that are seamless, mold resistant, fire resistant, and noise deadening. But what to do when plaster cracks, buckles, and pops loose? It's a perplexing question for many of our readers, including Tim Thorp, whose house in Providence, Rhode Island, is filled with badly blemished plaster. "How do I patch 100 years of gouges, cracks, and screw holes so the walls look flat and clean when painted?" he asks us in an e-mail. Here, Tom shows how to repair plaster walls to make them look as good as new.
Nitty-Gritty Plaster Repair Overview
The key to any fix is to reunite the plaster with the strips of wood lath underneath. Otherwise the cracks come back, no matter how many times you patch over them. That's why This Old House general contractor Tom Silva usually reattaches lath with screws and metal washers before attempting a repair. Recently, though, he tried Big Wally's Plaster Magic, a homeowner-friendly adhesive that uses glue instead of screws. While it costs more than the screw-and-washer method—a six-tube kit runs $120, versus $20 for 120 metal washers—the final finishing is easier and looks better because there aren't any washers to cover. Plus, a glued bond lasts longer than a screwed connection.