Brown Water Stains
on Ceilings and Walls
Brown or yellowish-brown water stains on ceilings or walls are almost always caused by water leaking through the drywall, where a stain appears or close to it.
Normally, if this was a leak of short duration, the drywall would re-harden and would not need repair. The process of removing the brown stains, which are really, water stains on ceilings or walls, can be done with either spray or paint sealer. You will need to cover the brown stains with a shellac or oil based primer/sealer such as a Kilz™ or a Zinzer™ product.
Be careful when using the above sealers as the spray can get on other things. When you are attempting to spray water stains on ceilings, the spray can drift where you may not expect and cause damage to other items. Even when using the sealer from a can, it can get things you don't want it to as you brush the paint over the stain. Cover items near and around where you are spraying or painting so you do not get the sealer on areas you do not want damaged.
A home remedy, that I have been told of, for removing water stains is to put some bleach on a sponge and work it on and around the stain. I think this might work on harder surfaced textures but not well on popcorn texture as you will probably take off some of the texture. I have not tried this, but if you do try it, especially to remove water stains from ceilings, is to make sure to wear protective gloves and eye protectors. Also, cover up things so that, you do not end up getting bleach your furniture or carpet.
Even though the bleach might work, I still prefer the sealer sprays for getting rid of brown stains and removing water stains. I know they work.
Remember: Painting over the brown stains with water based paint will not cover the stain!
If the water stains on the ceiling have been caused because a leak has occurred over a longer period of time, you may see sort of a bubbled surface where water has loosened the drywall along with the brown stains. You may have various colored mold growing, along with the brown water stains. Because mold damages and weakens the drywall,and also, can be detrimental to ones health, you will need to cut out and replace the drywall.
On rare occasions, the drywall may be salvaged when it has had a chance to dry out. If, after scraping the mold area, you find the mold is only growing in the painted surface, you can cut the surface paint and mold out, then seal the area and repair with drywall mud.
You may want to tape the cut edges so the paint does not curl up after you apply the mud skim coat. Then finish out the drywall for paint. But most often in these cases, you will need to cut the mold out and replace it with new drywall.
Caution: When dealing with mold problems, always wear a protective mask. Inhaling mold spores can be a health risk.