Do 1 Thing ENERGY STAR: Unlocking the Comfort and Savings by Air Sealing Your Attic

Attic Air Sealing

By: Doug Anderson

This week EPA invites you to “Do 1 Thing ENERGY STAR,” by sealing and insulating your home. This blog post is the third in a 5 part series from ENERGY STAR’s home envelope expert Doug Anderson about the benefits of sealing and insulating your home, and how you can get started this fall.

In yesterday’s blog, we covered how to check your home’s insulation levels and how to look for air leaks. We also covered how to use ENERGY STAR resources to help choose and prioritize your sealing and insulation projects.

To make the largest impact on your utility bill and comfort, you will want to start with the attic.  ENERGY STAR recommends that you always seal the attic first before adding any insulation.

Air sealing the attic: Do it yourself or hire a contractor?

Air sealing the attic is generally a challenging do-it-yourself (DIY) project, but can be well worth the savings in labor costs. If your attic is accessible and not too difficult to move around in, you don’t mind getting a bit dirty, and you enjoy tackling bigger home improvement projects, attic air sealing may be a good DIY project for you.

Even if you are not comfortable taking on this project yourself, don’t let that stop you – there are many qualified contractors who can do the job for you.

How to seal attic air leaks

If you have decided to do it yourself, you will want to start by identifying the locations of leaks, which was covered in the last blog.

Once you have found the leaks, they can be sealed using a variety of materials.  To seal the larger leaks use unfaced fiberglass insulation stuffed into plastic bags, rigid board insulation, a piece of drywall, or expanding spray foam in-a-can.  In some cases, you will need to use metal (such as aluminum) flashing and high temperature caulk to seal holes or gaps near areas that can get hot (such as near chimneys, furnace flues, or water heater flues). Then, seal smaller holes and cracks (under a ¼ inch) with long-lasting, flexible indoor/outdoor caulk like silicone or acrylic latex.

Safety First

After making home improvements that result in a tighter house, there can be an increased opportunity for carbon monoxide (CO) to build up if your gas- or oil-burning appliances are not venting properly.   Have your heating and cooling technician check your combustion appliances (gas- or oil-fired furnace, water heater, and dryer) for proper venting.  This testing is called combustion safety testing.  The testing is easy, but should be done by professional contractor who can sign-off that the systems are OK.

Also, in certain parts of the country, sealing may also trap dangerous indoor air pollutants (like radon) in your home.  To see if you live in these areas or if you just want to learn more about radon, check out the EPA website here.  You can test for radon yourself for a low cost, or hire a professional contractor to conduct tests and discuss solutions if they find problems.  The tests are easy and can give you peace-of-mind.

Additional information on achieving good indoor air quality and proper ventilation in your home can be found here.

Learn More

For more detailed instructions on how to identify and seal air leaks in the attic and throughout the home, visit the Seal and Insulate with ENERGY STAR website.

Do 1 Thing ENERGY STAR this week. Start sealing attic air leaks to unlock the savings in your attic!

Doug Anderson is an ENERGY STAR Project Manager and has been with EPA for 13 years. He works on issues related to the home envelope, including insulation products and energy efficient residential windows.

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