Condensation is water that forms when warm, moist air hits a cooler surface. In homes, it might occur on surfaces such as windows or on cold-water pipes. Excessive humidity is what causes condensation. Is it bad beyond some irritating fogging up? Yes. Excessive condensation can eventually damage windows and may also eventually lead to mold – and no one wants that.

A close up view of condensation forming on a window
A close look at how condensation can form on a window.

When interior humidity levels are too high in comparison to the cooler outdoor temperatures, condensation can form on the coldest surface in a room – often times the glass in a window or door. While windows and doors do not cause condensation, they may be one of the first places it shows up.

Can you control or reduce window condensation? Yes. Here are some tips:

  • Monitor the furnace humidifier and employ and monitor a interior humidifier.
  • Ensure vents for the attic, basement, and crawl space are open, adequately sized and cross-ventilated.
  • Run the exhaust fans for kitchen, bathroom and laundry rooms for longer periods.
  • Make sure exhaust fans vent directly outside and not into attics or crawl spaces.
  • Follow the manufacturer’s instructions for venting gas appliances.
  • Make sure your furnace is in proper working order and is serviced regularly.
  • Open a door or window for several minutes each day to refresh the inside air.
  • Open window coverings – like blinds or drapes – during the day to increase airflow over the glass.

Contact us to request an estimate if you’re considering replacing the windows in your home. Our team can answer your questions about window condensation and how you can prevent it further through product selection and other considerations prior to the purchase of replacement windows.

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