- 1). Seal the exposed drywall and drywall paper with an oil-based paint or shellac. Apply a single coat of this as a sealer using a paint brush.
- 2). Apply joint compound to the damaged areas of the drywall with a 10-inch broad knife. Spread the compound as thin as possible while still covering the damage. It should be no thicker than 1/16 of an inch.
- 3). Wait about four hours for the compound to dry. If you have several days to complete the project, you could wait overnight just to be safe.
- 4). Lightly sand the compound to remove rough spots, lines or grooves from the first application. Wipe away dust with a damp cloth.
- 5). Apply a second coat of joint compound to even out any dips in the first application. Scrape off excess compound after each application so you are not adding to the overall thickness, simply fixing imperfections.
- 6). Sand the surface of the drywall again to create a smooth, finished wall.
- 7). Use a paint roller to apply a final coat of sealer over the repaired drywall.