It happens to almost every homeowner. Whether it’s a burst pipe or a roof leak, you wind up with an ugly water stain on the wall or ceiling. While there are some good stain-blocking paints on the market, they don’t always work as well as you think.
As the coat of paint dries, the water stain begins to bleed through again. The solution is to encapsulate the stain with an impenetrable barrier.
My weapon of choice is a white shellac-based primer. The aggressive nature of the pigmented shellac locks the water stain in without ever having to worry about it bleeding back through.
Just make sure the source of the water stain has been resolved, and the stain is completely dry before applying the shellac primer.
Once the primer is dry, apply your choice of topcoat, and the stain is forgotten history.