When it comes to water damage, it's important to identify and address the underlying cause of the issue before you start painting. You should scan the area you are repairing to see if there are any damaged, broken, or severely fallen pieces of drywall that need replacement. If you find 'bubbles' in the paint caused by water getting under the paper on your drywall, you will need to remove the loose, peeling paint with a scraper and sand the damaged drywall with medium-grit sandpaper. If necessary, apply a patch to the area before applying a coat of primer and continuing painting.
Unfortunately, painting on water is only a temporary solution. Unless you fix the problem first, water damage will continue. To ensure that your surface is clean and protected from future water damage, make sure the water stain is dry before painting over it with a brush or roller. Blend the edges so that the paint blends into the surrounding area.
If you have water damage to the roof, you may be tempted to paint over it as a solution. However, Bob Vila recommends looking for and repairing water leaks first, or you'll find that the water stain on the roof keeps reappearing and your repairs will be short-lived. No matter how conscientious you are in maintaining your home, you will inevitably discover at one point or another that a pipe or roof leak has left signs of water damage to the ceiling or walls. If water stains are on the ceiling, then the most likely problem is a roof leak, probably near a vent, a vent pipe, a chimney or some other feature by which water tends to find a way in.
The first step in addressing the cause of water damage is to stabilize the area surrounding the leak. If your home has recently suffered water damage, it's important to deep dry it - removing not only visible water but also any moisture inside the wall or ceiling. Painting over a water-damaged ceiling is only possible after proper surface preparation and applying high-quality interior paint. You probably need to paint the entire wall or ceiling because it's very difficult to paint just one patch and get it to blend well with the rest.
If you have water damage and are looking for a paint company to repaint your wall or ceiling, Southington Painting Company and Williams Professional Painting will be happy to help. Painting surfaces in your home after water damage is very different from a standard job and requires special attention.