How to Fix a Sagging Plaster Ceiling
- 1). Drill injection holes every 3 to 4 inches into the ceiling hitting the lath -- but not drilling into the lath. Wear safety goggles to protect your eyes.
- 2). Vacuum debris with a shop-vac.
- 3). Squirt some water into the holes to soften the plaster and wet the lath. This will prepare for a strong adhesive bond.
- 4). Pump either latex or acrylic glue into the hole with a caulking gun until you feel a slight bulge. Clean any excess with a rag.
- 5). Prop up the ceiling with supports or screw a 1/4-inch-thick sheet of plastic-covered plywood into the lath. Remove after 24 hours. Scrapeoff any excess glue with a scraper. Allow to cure for another 24 hours.
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