Yellow ceiling stains can be unsightly, drawing the eye away from your decor. The stains may also serve as a clue to a larger underlying problem. Determine what type of stain you have so you know if it can cause potential health risks and the best way to clean or mask the stain.

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Water damage often leaves a yellow-brown stain on the ceiling.

Water Damage

Water damage typically leaves a yellowish-brownish stain on the ceiling in a somewhat circular shape with a darker outer ring. A leaky roof, broken plumbing pipes or an overflowing tub, sink or shower from a higher level can cause water damage. Ignoring the damage or prolonged leaks can lead to other issues, such as mold. Excess water can also ruin the actual ceiling and cause the paint to peel or curl.

Mold

There are numerous kinds of mold that come in different colors, including yellow. Mold can look like stains, except it will typically have a fuzzy or leathery appearance up close. It grows on wood and paper materials when enough moisture is present. If you discover mold on your ceiling, there is likely an underlying cause that you should address to prevent more mold from growing, as it can cause health issues.

Smoke

Exposure to nicotine smoke will leave a yellow stain on the ceiling. Smoke stains are generally different from mold or water stains and don't usually have the darker outer ring. If you try to wipe the smoky stain it will likely spread, especially if the ash is loose. The stains will turn black or gray if exposed to flame due to the the soot adhering to the ceiling.

Cleanup and Repair

Painting over a yellow stain is a temporary fix at best. Water stains will reappear if the original cause isn't dealt with. Replacing the actual drywall on your ceiling may be necessary when the drywall is riddled with mold or unstable due to prolonged water exposure. Remove any mold with a clean rag or sponge and throw it away. Brush a smoke stain to get all the loose ash and dirt off the ceiling and wash the ceiling before trying to cover it up. Use a stain blocker or sealer before painting to prevent the stain from bleeding through the new paint. You may have to repaint the entire ceiling if you aren't sure what color the ceiling is.