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Your Place: When should you sweat foggy windows?

You may think I'm all wet, but I've decided to talk about condensation, only because I receive a lot of questions about foggy windows in the winter.

You may think I'm all wet, but I've decided to talk about condensation, only because I receive a lot of questions about foggy windows in the winter.

Apparently, I'm not the only one.

"We often get calls from homeowners who are concerned that their windows are 'sweating' or leaking either inside or outside the home because they see moisture on the glass," said Christopher Burk, technical product manager at Simonton Windows in Columbus, Ohio.

That's simply not the case.

"While condensation may collect on the interior or exterior of energy-efficient windows, the units are really doing their job by helping serve as a barrier in the home," Burk said.

Windows don't cause condensation. They just prevent the moisture in the home from escaping to the outside.

"If the inside glass surface on double- or triple-glazed windows show excessive moisture, you can be reasonably sure that the moisture is also collecting on your walls and ceilings," Burk said. "This means you should take steps to reduce the humidity level in your home by using exhaust fans and dehumidifiers."

A lot of the water vapor is created by the inhabitants.

A family of four can add a half pint of water vapor every hour to the home just through normal breathing and perspiration. And, if you take a five-minute shower, you produce another half pint of water vapor. Even the simple act of cooking dinner on a gas stove can produce two and a half pints of water vapor.

Water vapor is part of our lives and our homes. To help control the amount of condensation in the home, experts at Simonton Windows recommend the following tips:

Use kitchen and bathroom exhaust fans.

If you have a humidifier, set it to the correct outside temperature.

If your home is overly humid, or if you have a damp basement, use a dehumidifier.

Properly vent clothes dryers, gas appliances and stoves.

Open a window in the bathroom.

Make sure your attic, basement and crawl spaces are well-ventilated and free from obstructions.

Store firewood outside. Freshly-cut wood can consist of up to 45 percent water, which adds water vapor to the home. Even well-seasoned firewood generally has a 20 percent to 25 percent moisture content.

Open curtains and blinds to allow more air circulation around your windows.

Homeowners with the most cause for concern are those with older, less efficient windows.

"Windows are just like any other major part of the home," Burk said. "They wear out over time and need to be replaced. If your windows have air leaks, don't close properly, or are failing to act as a solid barrier to the environment, then it's time to consider replacing them with energy-efficient windows."

Burk also recommends knowing the difference between condensation on the glass and between the glass panes of the window.

"If you see moisture, fogging or cloudiness between the panes of glass in your window, this indicates that the seal of your window has failed and it's time to get a new window," Burk said.

"Failed seals lack the energy efficiency and features necessary to help you keep energy bills low and enjoy comfortable living in your home," he said.

"While condensation on the interior or exterior of the glass is manageable, moisture between the glass needs swift attention by homeowners," according to Burk.

Energy facts

 Some ideas from Emerson Corp.:

Heating and cooling systems use more energy than electronics, appliances and lighting combined.

Over the next 10 years, as older HVAC systems are replaced with newer, higher efficiency equipment, consumers will likely realize energy cost savings of more than $30 billion vs. what they are paying today.

In a September 2011 Emerson survey, the majority of consumers surveyed have made only small home energy upgrades such as installing a programmable thermostat or switching to compact fluorescent lightbulbs.

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