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Problem:

Moisture on windows, leading to condensation, frost or pools of water on the windowsill.

Diagnosis:

Inefficient windows (e.g., single pane with aluminum frames) or high moisture with inadequate ventilation. Moisture in the air condenses on the cold surfaces of your windows when it is cold outside. Continued excess moisture can lead to mold and mildew.

Prescription Checklist:

• Avoid mold and mildew by making sure that moisture can escape through proper ventilation in the kitchen, bathrooms, and laundry room.• If you have single pane windows, especially with metal frames, install storm windows or consider replacing your existing windows with ENERGY STAR labeled windows.• If you have a humidifier, check for proper operation so not to add excessive moisture to your indoor air. The humidifier setting should be adjusted with large swings in outdoor temperature.