How to cover water stains on a ceiling or wall
A common issue many homeowners want to remedy is water marks or stains on a ceiling or wall, often caused by a leaking heating or domestic water system.
Although many people believe that simply painting over with emulsion will hide or cover these unsightly water marks, this will not work. The stain will simply "bleed" back through the top coat every time you try and paint over it. Sounds familiar?
Treating these marks with a "stain sealer" (sometimes called a "stain killer" or "stain block") prior to painting with emulsion is the only way to achieve your desired result.
Personally, I use two coats of good quality stain sealer over the stain, then at least two top coats of emulsion.
Remember, always top coat the entire ceiling/wall where the water stain is, not just the area of the stain. This will ensure that you get an even and flawless finish.
Please note, this process only works if the water stain is already cured and dry. Ongoing damp issues need to be resolved before any paint work commences.