Painting over wallpaper is sometimes the best route to take when removing the wallpaper might damage the wallboard. It can also be the best choice when you are unable to spend the time it takes to remove wallpaper, or are uncertain if it can be removed safely. Some people recommend you never paint over wallpaper because the paint can cause the wallpaper to buckle, but if you do the job right, the chances of that happening are slim.
Painting over wallpaper can be done, but it requires some wall preparation. You cannot just begin painting without first priming the walls. Latex paint can seep through wallpaper and eventually make it buckle. It can also cause the wallpaper seams to curl which will then make your new coat of paint look very bad or cause it start peeling.
Painting Over Wallpaper
It sounds like wallpaper should always be removed, and that should be the first option considered. There are chemicals that make it easier than ever to strip wallpaper. But in older homes, wallpaper was probably applied directly to an unpainted or unprimed wall. Removing the wallpaper could rip the wallboard, so it's advisable to leave the wallpaper in place in this situation. Damaging the wallpaper turns a fairly simple job into a major repair.
Removing wallpaper can also take some physical effort and not everyone is able to exert themselves in that manner. Painting over wallpaper is much simpler and requires a lot less effort. But you do have to prepare the wallpaper properly so you don't end up with continual problems.
First you should make sure all loose paper is removed so it doesn't bubble under the paint or cause rough spots. You need to apply a thin layer of wallboard compound along the seams, making sure the areas are smooth. Then you can paint the wallpaper with an oil-based or alcohol-based primer. Alcohol or oil based primer does not have water that can soak through wallpaper causing it to lift from the wall.
It is advisable to use a flat paint, which will hide flaws in the wall much better, than a paint with a sheen or gloss. Painting over wallpaper requires applying two coats of paint. In the end, you'll have beautiful new walls and no one will know you ever had wallpaper at one time.
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