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    260 East Boulevard North Hagerstown, MD 21740
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Underfloor Insulation: What to Know

As a homeowner, you may know a little bit about insulation and what it does. You probably even know that your attic and walls should be insulated. But what about the floors? Keep reading to learn more about installing insulation under your flooring!

Should I Insulate Under My Floor?

It’s a good question, one we often hear. Floors above cold spaces—like vented crawl spaces and unheated garages—should be insulated, but don’t forget about under the flooring. This will help ensure maximum energy efficiency for your home.

According to the U.S. Department of Energy, it’s ideal to insulate:

  • Slab floors built directly on the ground
  • Foundation walls of unvented crawl spaces (as an alternative to floor insulation)

An insulated slab is easy to heat, and placing the mass of the slab in your house’s thermal envelope helps keep interior temperatures comfortable. Most slab insulation is done during home construction. While insulating a slab in an existing home can be more expensive and a bit more invasive, it is possible to dig around the perimeter of the house and install insulation, typically foam board. Insulating the exterior edge of a slab can reduce heating bills by 10 to 20 percent in many homes! Foam-in-place insulation can also be blown under floors to help insulate and reduce air leakage.

It’s a good idea to install an air barrier—caulk, foam sealant, etc.—to help prevent cold air in the garage from “short circuiting” the insulation under the subfloor as well.

Underfloor Insulation in Maryland & DC

If you’re located in the Washington, DC metropolitan area, call the team at Accurate Insulation. We install floor and underfloor insulation and have experience with new construction and retrofit projects of all kinds. Contact us today to learn more!

Products We Install

Our insulation team adds energy efficiency, comfort & value to homes & buildings.

Spray Foam

Accurate Insulation is proud to be a leading installer of spray foam insulation.


Environmentally friendly and effective, cellulose works well in homes and buildings.

Radiant Barrier

We can help keep your home cooler and more comfortable with an attic radiant barrier.

Garage Doors

When you turn to Accurate Insulation for garage doors, you work with a great team.


No matter your gutter needs, the Accurate Insulation team has you covered.

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