QI have a vaulted ceiling and have red spots showing up. It looks like someone flicked spaghetti sauce on the ceiling. What are these, and what is causing them? What should I do about them?
AIt's difficult to know for sure without seeing the spots. However, there are a couple of possible explanations:
Sometimes the ingredients in latex paint will leach through to the surface, appearing as rusty brown or tan spots. They're often glossy or sticky. This typically happens in ceilings of rooms with high humidity, such as bathrooms.
If that's the cause, the spots can be removed with soap and water. To remove the stains, wash the affected area with soap and water, then rinse. You may have to repeat the process a couple of times before the leaching stops.
Lowering the indoor humidity is generally a good idea and it will help prevent this from happening again if you remove the spots or repaint to cover them.
The spots also may be mold. Mold is often dark, but it can come in other colors. To test for mold, touch the spots with a cotton swab that has been dipped in household bleach. If the stain lightens or disappears, it's probably mold.
You can remove mold by washing the wall with a general household cleaner. Rinse. Then wash again with bleach and water mixture (one part bleach to four parts water).
Mold means you have a moisture problem. You have to eliminate the moisture to prevent the mold from returning. Again, lowering the indoor humidity would help.
But sometimes construction defects in vaulted ceilings allow for condensation during cold months, or water leakage. That moisture can create conditions for mold growth. It also can mean mold lies behind the ceiling's surface. For more information about that possibility, contact the Minnesota Department of Commerce's Energy Information Center at 651-296-5175 or 1-800-657-3710. Also, visit the Minnesota Department of Health's Web site: http://www.health.state.mn.us. Type "mold" in the search box.
If you suspect a construction defect and the house is less than 10 years old, call the builder for advice.
If it's older than that, or if the contractor won't respond, contact your local building official.
Mold behind the ceiling surface may or may not be a problem once you eliminate the moisture sources and clean up visible mold. But in any case, make remedies so mold won't recur. Mold not only affects the durability of your house; it also can be a health risk.
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