Window Condensation... Are My Windows Defective?

- My windows have condensation on them. Are they defective?
- When Condensation Is Appealing:
- Why Does The Condensation Collect On My Windows And Not on My Walls?
- Glass A Poor Insulator?
- So Is It OK To Have Condensation?
- Taking Action
My windows have condensation on them.
Are they defective?
If you are troubled during the fall and winter by condensation on the windows of your home, you aren’t alone. Window condensation is a common problem in cold climates. Understanding what causes the condensation is the first step in solving the problem. If you are experiencing condensation on the surface of your windows they are not defective but conditions may have been unintentionally created that caused a “dew point”. Simply put the dew point is the temperature at which the water vapor in the air becomes saturated and condensation begins on solid surfaces.
When you take a cold refreshing beverage out of the cooler on a hot day, what happens to the outside of the beverage container? It gets wet with condensation! Without getting too scientific, that is a normal reaction when cold air meets warm air. This condensation reaction is even capitalized on in advertisements to make a beverage even more desirable.
Why Does The Condensation Collect On My Windows And Not on My Walls?
The fast answer is because humidity cannot pass through the material glass while it does pass through sheetrock, wood, siding and even sheet plastic. Also your walls are constructed in our area to be 4 or 6 inches thick while the insulating space in your glass is only 5/8 inches thick making glass a very inefficient insulator.
If Glass Is A Poor Insulator, Then Why Are My Windows Not Totally Covered In Condensation?
Your recent ancestors grew up in houses with single pane glass. If it is zero degrees outside and 70 degrees inside, the inside surface temperature of the glass is only 14 degrees!! It was typical for not only condensation to form on the glass but the window covered with frost as well. Glass manufacturers started using double pane glass with a space in the middle of the two panes calling it “Insulated Glass”. Research indicated that a space of 5/8 of an inch was the perfect air gap. More than 5/8 inch and the air would begin to move inside the gap because warm air rises thus reducing the insulating value. Later years glass companies began developing films on the glass that increased efficiency by reflecting the heat back to the source of the heat. Later still argon gas was added in-between the panes to achieve maximum thermal benefit. With these improvements, you can take the same 0 degrees outside and 70 degrees inside and have an inside glass surface temperature of about 56 degrees. This significant improvement however is still no match for sub-zero temperatures outside and high humidity inside.
So Is It “OK” To See Some Condensation On My Windows?
Just as seeing an ad of a beverage container soaked in condensation reminds you of how refreshed you were the last time you held an ice cold beverage, condensation on your windows should be a reminder for you to look into a potential problem. Condensation that collects on your windows means there is a potential this humidity is collecting elsewhere in your home undetected for instance inside your walls. If your house cannot vent out the higher humidity fast enough using normal means, you may need to take action (See “Taking Action” below).
· Are any heating vents blocked?
· Are you unknowingly contributing to a higher humidity level by not running the bath fan when taking a shower?
· Are you cooking up a meal on the stove, or washing dishes?
· Are you watering a high number of house plants daily?
· Are you washing floors or other surfaces?
· Do you have a large family or maybe you are entertaining guests during a holiday. Each person’s respiration alone in the house adds nearly a half gallon of water each day to the humidity in your home.
Scott’s Lumber offers you some of the best windows and glass technology for our area of the country. We would not be doing you a service by selling you a triple pane window that was designed for Canadian climate. The cost difference on such high test windows would take many more than the acceptable 5 year energy payback consumers expect today. Sometimes when our climate reaches its extreme coldest; seeing a little line of condensation at the bottom of your window glass cannot be avoided without extra effort by the homeowner.
If the condensation drips on to any finished wood surfaces, the moisture will eventually begin to deteriorate the finish.
Here are some self help things you can do yourself to reduce the humidity in your home during severe cold snaps and help reduce condensation on your windows.
· Bathroom:
o Run bath fans longer than usual to help remove more of the shower steam.
o Take shorter showers and even cooler showers reducing steam output.
· Kitchen
o Run exhaust fans longer (providing your fan exhausts to outside)
o Select meals that are less steam producing during preparation.
o Do not open the dishwasher during its cycle or any time you would release extra steam into the air.
· Clothes Washing
o Avoid opening the washing machine door during its cycle
o Avoid opening the dryer door during its cycle
o Try to schedule clothes washing separate from shower and cooking times
o Avoid washing clothes that have to drip dry.
· General
o Make sure furniture or other items do not block any furnace vents around the home.
o If you have a humidifier, reduce the relative humidity setting as it gets colder outside.
o Open the shades or curtains on affected windows to allow air flow to the glass surface and natural evaporation to take place.
o If you have a large number of house plants you water in one room, try dispersing the plants to other rooms to even out the individual room humidity. Also if your bathroom is near this room it may be helpful to run the bath fan several times a day to help draw the humidity down.
o Depending on the severity of your problem, open the doors and windows of your home several times a week to allow an exchange of your high humidity air with the low humidity outside air.
o You can use a fan if the problem is isolated to only a couple of windows, or if the problem is most severe on a patio door or bow window where it is difficult for air to circulate.





