Water damage can be a homeowner's worst nightmare. Not only do you have to find and repair the source of the leak, but you also have to repair the damage it caused. Painting over water damage is a bit different from a standard painting job, as it requires some preparatory work. Christian Lacroix, owner of the Texas-based Handyman Connection of McKinney, provides a step-by-step guide on how to paint over water damage.
The first step is to thoroughly clean the area damaged by water. Scrape off any peeling paint and check for any damaged, broken, or very saggy pieces of drywall that need to be replaced. If there are “bubbles” in the paint caused by water seeping under the drywall paper, remove the loose paint with a scraper and sand the damaged drywall with medium grit sandpaper. Place patches on the area if necessary.
Once the area is prepped, apply a coat of oil or alcohol-based primer with a brush or roller and allow it to dry between coats. This seals in any residual moisture and prevents the stain from penetrating. If there is mold or mildew present, clean it with a dilute mixture of chlorine bleach and water before priming. Finally, paint the area with two coats of paint.
Be very careful when painting over any baseboard or piece of ceiling molding that shows signs of water damage, as some of them may be made of wood composites; they may need to be replaced rather than repainted. Painting over water damage is a tedious process, but it's important to take your time and do it right. If you don't find and repair the source of the leak first, you'll find that the water stain on the roof keeps reappearing and your repairs will be short-lived.