My house has a crawlspace under it, and the floors get very cold in winter. What is the best way to insulate a crawlspace on a budget?

– Margaret

Hi Margaret,

Having a crawl space under your house can make your home colder in the winter than a house built on a concrete slab. Also, mold and mildew can be a problem in a crawl space, so you need to be sure to guard against that as well.

To make the floors in your home warmer, and prevent mold and mildew from forming in the crawl space, requires more than just insulation.

The dropdown tabs below discuss how to go about reducing moisture and insulating a crawl space under your home:

Start by removing any items stored under your house, as well as any construction debris, such as scraps of wood or broken bricks. Next, even out the dirt in the crawl space, and correct any problems you might have with water standing under your house by filling in any holes or depressions.

Finally, cover the entire area under the house with a layer of 6-mil plastic sheeting. Overlap the sheets a foot or so, cut the plastic around piers, and run the plastic all the way to the foundation walls. As an added measure, you can tape the seams in the sheets together to keep the plastic in place.

Fiberglass insulation batts or rolls are the most economical and easiest DIY choice for insulating between the floor joists in a crawl space.

The U.S. Department of Energy recommends R-11 (3½”) insulation under floors in warm climates and an R-25 (6” to 8”) in cold climates. Install the insulation with the paper vapor barrier facing up toward the heated living space, and make sure the insulation fits tightly between the joists.

Hold the insulation in place from below using insulation support wires or by stapling chicken wire to the bottom of the joists.

If your foundation isn’t enclosed, fill the space between the exterior piers with bricks, concrete blocks, or lattice panels. To install brick or block walls, pour a concrete footing between each of the piers around the outside of the house, then lay bricks or blocks on the footing.

Install foundation vents in the walls so there is one square foot of vent space for every 150 square feet of crawl space.

Another option is to make 2×4 frames from pressure-treated wood to fit between the piers; then cover the outside with lattice, and staple landscape fabric on the inside to reduce (but not stop) air infiltration under the house.

Good luck with your project,

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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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