The answer is humidity and condensation.
Warm, indoor air can condense around cold drafty windows, making them “sweat” with moisture. This moisture causes the window sills and trim to become damp. If the moisture is not dried, mold will begin to grow.
Most of the time mold growth is found on old windows. Older windows can be drafty thus allowing cold air to creep in. When the cold air combines with warm indoor air, condensation occurs.
New windows are a big expense but are a great investment. Not only can they help prevent mold growth, they can also reduce your heat bill.
For a less expensive option you can add storm windows and weather-stripping.
This will accomplish much of what newer windows do but for a fraction of the price.
To help prevent frost build-up, condensation, and cold drafts:
Keep shades or curtains open as much as possible to let in sunlight. The sunlight will help warm up and dry the windows.
Turn off your humidifier in the winter or just run it less frequently. Your home may not be as dry as you think.
Invest in a hygrometer to keep an eye on your homes humidity level.
Areas in your home that should be vented properly:
Mold on windows isn’t a major problem until it spreads. Therefore routine cleaning and prevention is necessary to avoid a greater issue. Home owners can remove it with a mild detergent. If there is staining left you can use bleach to remove.
However, cleaning the mold is only temporary. Prevention is the only way to prevent mold from coming back.
If the mold has spread to the drywall contact a licensed mold remediation company like us.
Mold growth can be alarming and we understand. If you come across mold growth on your windows or anywhere else in your home feel free to give us a call. We would be happy to answer any questions you may have.
Just remember mold growth can be avoided with proper prevention! Check out more of our blog posts below to learn more!