Insulating the space between the joists in a basement or crawlspace can help reduce your energy bills. Here’s how to insulate under a floor:

  1. Cut the insulation to length using a square and sharp utility knife.
  2. In older homes, where the spacing of the floor joists varies, you may need to cut the insulation to width as well.
  3. Install the insulation with the vapor barrier facing up toward the heated living area of the house. If both floors of the house are heated, use unfaced insulation.
  4. Don’t compress the insulation when installing it, but allow it to expand to fill the cavity.
  5. Hold the insulation in place using support wires beneath it. Cut to length if needed using wire cutters.

Watch the video above to find out more.

Related: What is the Optimal Subfloor Thickness for Insulation?

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Danny Lipford

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Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio, TodaysHomeowner.com, and Checking In With Chelsea, a décor and lifestyle blog.

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