Your best option for a base coat to cover water stains on the ceiling is an oil based mold resistant stain blocking primer in a shade closely matching that of the existing ceiling.
Covering water stains on ceiling.
Apply the solution on the ceiling using light and controlled strokes.
Purchase a spray can of stain blocking primer or sealer.
If pieces of the ceiling and not just the.
Spray cans work better than a brush especially on popcorn or textured ceilings.
If you have a coloured ceiling use oxygen bleach rather than chlorine bleach.
Use a sponge or rag that s damp with clean water to wipe the bleach mixture on the ceiling in a controlled manner.
Follow these steps when covering over a water stain on your ceiling.
Mix 1 part bleach with 3 parts warm water.
Dip a sponge in the mixture and standing on a stable stool or stepladder wipe the stain.
Start by finding the cause of the leak and repairing the problem to prevent damage in the future.
Wear protective eye wear as the bleach is a fluid you will need to apply above your head.
You need to cover the stains with primer before painting and drywall primer won t do.
Use a clean sponge or rag and dip it into a mixture of water and bleach.
Cover the floor with plastic and find a good pair of goggles drips are a fact of life when painting the ceiling.
For lighter woods like knotty pine you can use oxalic wood bleach to remove the dark stains caused by water.
Use shellac based stain blocking primer or an equivalent high solids latex primer.