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What Causes condensation?

Condensation is when water vapor (humidity) changes from air to liquid. This liquid forms into droplets on glass surfaces in a home. Water droplets inside your windows, patio doors, or skylights are an indication of excess moisture in your home and is not formed by water ‘sweating’ into the home. The glass is only a collector of the water that is already in your home condensing from the cooling air.
  • The air around us contains humidity, and additional humidity is created by cooking, cleaning and showering, thus forming condensation. Condensation is most noticeable on skylights because warm, moist air rises to the ceiling and is more prevalent in new homes. After a few years, new homes tend to dry out and have less moisture problems.
  • This is a more common problem in winter months when the cooler outside temperature difference is much greater and you begin to heat your home.
Condensation Kitchen

Condensation can build up in high humidity areas of your home like the kitchen, bathroom, or laundry room.

The Problem Is Excess Humidity

  • Condensation is an indication that your humidity level is too high; there is too much moisture in your home. You can see this happening on your exterior glass products.
  • Excessive moisture in your home can cause damage to your home in the form of warp, rot, and paint chipping. Most likely, when you have condensation on your windows, patio doors, and skylights; this is also happening in your walls.
  • Normal activities of showers, cooking, dish washing, and even breathing release water into your air. Other common factors include gas appliances, large fish tanks, and house plants.
  • The problem is more common in newer built homes where the construction methods are ‘tighter’ than older homes which were built more breathable. Tighter built homes have far greater energy and heating efficiencies but tend to trap humidity in as well. Older homes allowed the gained water vapors to escape out, as well as the heat.
  • This phenomenon occurs generally with rapid decrease in outside temperature in the fall season. During this time, there is a greater difference in temperatures between the warm interior of your home and the colder outdoors. You can decrease the amount of moisture in your home by using a dehumidifier and providing adequate ventilation and air circulation.

Condensation Diagram

  1. Water from washing, cooking, breathing or perspiring evaporates and becomes airborne.
  2. Water molecules move closer together as they get colder.
  3. When molecules reach a cold surface, such as glass or painted walls, as they grow they merge together.
  4. At ‘dew point’ they form visible drops, and condensation forms on the cold surface.

How to Reduce condensation In Your home

Condensation Humidity

Limit the amount of humidity
  • Ventilate regularly for five minutes at least three or four times a day if possible, maintain a constant room temperature.
  • Make a regular practice to ventilate your home, opening windows and skylights to flush your home with fresh clean moisture free air.
  • If possible, do not dry your laundry inside the house.
  • Close the doors of kitchens and bathrooms when in use, and use the extraction fans.

Condensation Air Flow

Improved Air Flow
  • The best way for limiting condensation on skylights is to make sure to have air moving in the skylight wells at all times.
  • Install a ceiling fan that moves air in the direction of the skylight. You can also install an exhaust fan in the sidewall of the skylight well. Of course, purchasing skylights that are built with adequate condensation channels, and ensuring the skylights are properly installed, is critical to controlling condensation.
  • A third option would be to install a Columbia venting skylight. These skylights can be opened with manual or electric controls to eliminate the warm, moist air within a home.

Condensation Vent

How to properly vent problem rooms like the kitchen or bathroom
  • Showering, cooking and laundry release significant moisture into the air, make sure this humidity can escape from your house easily.
  • Use your bathroom and kitchen ventilation fans every time you cook or shower.
  • You want to run the fans for about 15 to 20 minutes after you shower or cook.
  • On a regular basis check you vents are working properly and are not blocked by dust build up.

Hot Air Rises Mask

Hot air rises, so venting skylights can help fight condensation
  • Keep attic vents open. Warm, moist air rises and will be vented to the outside.
  • Hot humid air rises, if it isn’t too cold, you can open your venting skylights.
  • This will release some of the warm, moist air that is trapped in the house.
  • See Columbia’s line of manual and electric venting skylights.
  • Maintain a constant thermostat setting throughout the day.

Condensation Home

Circulate the air in your home
  • It has become a common practice to flush your home with fresh air on a regular basis, removing odors and interior pollution like dust.
  • Venting skylights can be opened to create a gentle cross wind to help move the air around your home.
  • Keep interior doors open. For a short time every day, try to vent air by opening windows in your home. Open a window while showering or cooking.
  • Use your ceiling fans year round, even in the winter to circulate the air in your home. Set your fan in a clockwise direction to push warm air off of the ceiling back down to the floor.

Condensation Dehumidifier

Buy a dehumidifier
  • Purchasing a dehumidifier is an easy, inexpensive way, to remove the moisture in your home. If a full size dehumidifier isn’t practical, you can also look into purchasing a mini dehumidifier.
  • Some dehumidifiers will need to be turned on and off, while others will come on automatically when the humidity level in the home reaches a certain point.

Condensation Turn Down Humidifier

Turn down the humidifier

The use of a humidifier can cause condensation because it releases moisture into the air.

If you use a humidifier in any part of your home (including the humidifier that works with some furnaces), try turning it down.

Condensation Plants

Move your plants
  • House plants release moisture into the air. If you have plants by your windows.
  • Moving them to a different location can help reduce condensation on the windows.

Condensation Natural

Condensation a natural occurrence and not a warranty issue
  • When condensation forms on the inside pane of a skylight it is caused by humidity in the home and is not a warranty issue.
  • Condensation forming between the panes of an acrylic skylight is a structural phenomenon caused during changes in temperature and humidity levels – it will naturally dissipate.