5 basics about air sealing for single family homes

Air Sealing has become the top home upgrade of energy efficiency experts, as it is an excellent way to increase your home comfort and reduce energy bills. Here are the 5 basic things about air sealing you need to know to determine if you can benefit.
Posted On: February 14, 2014

1. Sneaky leak spots

There are more places where air leaks in and out of your home than you may be aware of. Most people recognize that air leaks around windows and doors, but this illustration from the Department of Energy’s Guide to Air Sealing*, shows 19 areas of the home where measurable air leaks can affect air quality and energy loss. For example, did you know that air leaks around every single electrical outlet and switch plate in your house?

air leakage and sealing

2. Find a balance with fresh air allowance

Every penetration through the sides, roof or underside of your home has the potential to leak if not sealed properly. That includes windows, doors, vents, pipes, electrical cords, hose bibs and more. But before you seal, you must determine how much fresh air is needed to ensure healthy indoor air quality and ventilation of combustion equipment. Without proper ventilation, harmful gases could remain in your house (such as carbon monoxide) and/or water vapor could accumulate presenting a danger from mold and mildew. When we talk about “combustion equipment”, this includes anything that burns a fuel, whether that is natural gas, propane, or wood. Examples are:

  • Furnace
  • Washer /dryer
  • Gas stove
  • Fireplace
  • Water heaters

3. Weather stripping

The easiest Do-it-Yourself leak fixes are weather stripping doors and caulking windows. Materials to do weather stripping and window caulking can be purchased from most hardware stores and applied by the homeowner. Most window companies require caulking to be done in order to maintain warranties for their windows. So it’s a good idea to do it annually, or at least check it for wear annually. Caulking around flues, vents and pipes is recommended to be done by a professional contractor using caulking materials that are safe for the application.

4. The fireplace culprit

Your windows and doors may be closed and sealed, but there may be another big hole open for air to escape. Fireplaces can leak through the flue not closing tightly, through small cracks in the masonry chimney, or from the penetration of the chimney through the roof. During a home energy audit, air leaks from your chimney will be identified, but beyond that, chimney inspection should be performed on a routine basis, if only to make sure animals haven’t nested in it. The National Fire Protection Association says “chimneys, fireplaces and vents should be inspected at least once per year for soundness, freedom from deposits and correct clearances”.

5. Fact check from other experts

According to the US Department of Energy “air sealing is one of the most cost-effective ways to improve the comfort and energy efficiency of your home. Hire a certified professional contractor for best results”. We didn’t make that last part up.

Consider a home energy audit

A certified home energy auditor is trained to assess the air sealing and ventilation needs of your home. They use technology such as blower doors tests, infrared cameras and other measures to locate sources of air leakage and ensure adequate ventilation. The auditor is trained to look for safety and health issues, and local building codes. Why does this matter? Because you can actually over seal your house, locking in carbon monoxide from gas appliances.

Washington Energy Services provides BPI certified home energy audits and air sealing services. Learn more and see if your home might benefit from an audit.

 

* Source “Retrofit techniques and technologies: Air Sealing – A guide for contractors to share with homeowners,” Vol 10., Building America Best Practices Series, Prepared by Pacific Northwest National Laboratory and Oak Ridge National Laboratory for the US Dept. of Energy (April 12, 2010)

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