Why does condensation form on your windows, and what you can do to prevent it? Common results due to damage from condensation are:

  • Mold Growth
  • Paint peel and Stain Damage
  • Wet or Dry rot on window sills
  • Window damage around sash
  • Staining of carpets or damaged hardwood floors
  • Drywall damage

First let’s explore the cause of condensation; the why part of how condensation occurs. Excess humidity manifests itself in the form of condensation around the coldest area of a wall, such as in the area near windows. The warmer the air, the more moisture it will retain, and so when air in your building comes in contact with the colder glass surface, it is subsequently cooled and moisture is released in the form of condensation on the glass.

Air contains water vapor in varying quantities, with the capacity related to the temperature – warm air holds more moisture than cold air. When moist air comes into contact with either colder air or a colder surface a dew point is reached, and the air is unable to retain the same amount of moisture releasing water in the air or on the surface.

Can you reduce the condensation on my windows? The short answer: yes. In order to reduce condensation, humidity must be controlled and air movement must be generated. As the exterior temperature drops, the humidity level needs to decrease if the condensation is to be controlled. Indoor humidity levels should be maintained between 30% – 50% at a temperature of 75 degrees.

Increase ventilation in areas which produce humidity like bathrooms, laundry rooms, and kitchens. Be sure to properly vent the air outside the structure, and not into another space such as an attic. Dehumidifiers may be needed in basements or areas in a building with a large water source like an aquarium or large fish tank. Humidifiers can create problems, whether it is attached to the furnace or installed in a room, so be careful not to overuse or exceed the humidity range.