from Tim in Cudahy, WI:
#56
I noticed mold on my bathroom ceiling. Where does this come from and how can I get rid of it?
Mold and mildew may be signs of excess moisture.
No one ever wants to see mold growing in any area of their home. Condensation on windows, water stains, mold and mildew on walls and ceilings can be symptoms that indicate excess moisture in the home, or they can be a sign of a poorly insulated wall, air leakage, poorly performing windows or extremely cold outdoor temperatures.
Whether the problem is localized (a spot on the ceiling, wall or corner) or in a large area, you want to make sure you first rule out the possibility of a water leak. If it's not a water leak, then it might be caused by high humidity.
Consider the following:
- Do you have a crawlspace under your house? A dirt floor in a crawlspace should be covered with a continuous plastic (vapor barrier) to prevent moisture from the soil increasing humidity levels in your home. All vents and cracks to the exterior should be sealed to prevent warm humid air from entering the crawlspace. If there is standing water or the soil is wet, dry it out with fans before covering the floor.
- Your clothes dryer should be vented directly to the outside. Inspect the vent duct. Make sure it is attached securely to the dryer. Check that it is clear of obstructions (such as lint). Check for holes that leak air. If vent duct is damaged replace it with a metal duct. The vent duct should be cleaned at least once a year.
- Keep air conditioning drip pans clean and the drain lines unobstructed and flowing properly.
- Ask a heating and cooling contractor to check your heating and cooling system to make sure it is sized and operating properly to remove humidity. If your system is too big or the airflow incorrect your air conditioner may not remove humidity like it should.
A Home Performance with ENERGY STAR partnering consultant can also help you determine if your home needs more ventilation, if air sealing is needed, if your ducts are leaking and make sure your duct system is properly sized and air flows to each room. Learn more about the Home Performance with ENERGY STAR Program and a home energy evaluation here. To see the process online, view a video or an online demo