Are Your Walls Insulated? Here's How to Find Out

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    How to Check Your Own Walls for Insulation

    under construction
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    It's a question that can drive homeowners to the edge of insanity when extreme cold or hot weather roll around: "The AC/furnace is pumping like crazy. I have decent windows. I have weatherstripping. Where is all of my cool/warm air going? Do I even have insulation in the walls?"

    Unless you bought the house new, built it yourself, or remodeled it yourself, this is a completely valid question.

    For instance, if you plan to remodel your kitchen, you want to know in advance if you will have to gut to the studs and install insulation (or blow in insulation). There are millions of ways to find out if you have insulation.

    You just need to gain access through any small hole in an interior wall. Sometimes you can slip around the sides of existing holes (heating vents, removable electrical receptacles, etc.) or by looking for tell-tale entry points in either the attic or basement.

    Another way is to schedule a time with an insulation company. They will poke around and graciously let you know if you have insulation, what kind, and how much.

    But if you want to quickly get to the heart of the matter, grab the following tools:

    • Hole saw
    • Flat pry bar
    • Brad gun
    • Inspection scope (optional)
    • Stud finder
    • Hammer

    Depending on the setup of your home, you'll want to either go low and test a spot along the floor, or go high and check above the kitchen cabinets.

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  • 02 of 12

    Go Low: Knock Off the Baseboard or Shoe Molding

    Insulation in Walls - Knock Off Baseboard or Shoe Molding
    Lee Wallender/

    Gently insert your pry bar behind the shoe molding or baseboards (the trim that runs along the bottom of the wall).

    If you're worried about damaging your walls, put a piece of thin board behind the pry bar.


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  • 03 of 12

    Go Low: Put the Base Trim to the Side and Remove the Brads

    Put Base Trim to Side, Remove Brads
    Lee Wallender/

    Pry back the baseboards. These moldings are usually secured only by brads and are easy to remove.

    Use your pliers and pull straight back to remove any wayward brads protruding from the wall.

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  • 04 of 12

    Go Low: Look Under the Slit

    Fiberglass Insulation Under Wall
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    Drywall will often have a space at the bottom as a normal part of installation. You might be able to see fiberglass or the paper facing of fiberglass insulation. In fact, if you do have fiberglass, chances are high that this stuff will be smushing out of the bottom. Blown-in insulation will be visible through this slit, too.

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  • 05 of 12

    Go Low: Locate the Studs

    Insulation in Walls - Locate Studs
    Lee Wallender/

    No existing slit under the drywall? No problem.

    First, locate a space between two studs.

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  • 06 of 12

    Go Low: Cut a Hole Near the Floor

    Insulation in Walls - Cut Hole Near Floor
    Lee Wallender/

    Now, cut a 3/4" hole in the drywall near the floor but still below the level of the baseboard.

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  • 07 of 12

    Go Low: Run the Inspection Scope

    Run Inspection Scope
    Lee Wallender/

    Peek in. An inspection scope really pays for itself at times like this. It's certainly nice to be able to run the scope up a few feet and see what's going on.

    A wire hanger also allows you to probe around.

    It's pretty obvious that you have no insulation if you can get a scope or wire up the wall cavity. But blown insulation might be deceptively creating a pocket, and the wire or scope will loosen the pocket.

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  • 08 of 12

    Go Low: Staple the Baseboards Back in Place

    Staple Baseboards
    Lee Wallender/

    Staple your trim back with your brad gun. No need to repair the hole in the drywall (unless you want to), since the trim will cover the hole.

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  • 09 of 12

    Go High: Locate an Out-of-the-Way Place Such as Above the Kitchen Cabinets

    Locate High Place, Kitchen Cabinets
    Lee Wallender/

    Another angle on the matter is to go high instead of low.

    Locate a high area that is fairly unobtrusive. In kitchens, this will be above the cabinets. In bedrooms, this will be inside closets.

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  • 10 of 12

    Go High: Cut Hole in the Drywall

    Cut Hole in Drywall Over Kitchen Cabinets
    Lee Wallender/

    Cut a 1" hole in the drywall over the kitchen cabinets. The lower, the better—but not so low that you're affecting the cabinets. Like before, you'll want to locate studs so that you don't inadvertently try to cut into a stud.

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  • 11 of 12

    Go High: Remove the Drywall Plug

    Remove Drywall Plug
    Lee Wallender/

    Be careful that you do not lose the drywall plug. You will reuse this when later fixing the hole in the drywall.

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  • 12 of 12

    Go High: Run the Inspection Scope or Wire

    Inspection Scope Shows No Insulation
    Lee Wallender/

    Run the inspection scope or wire down. Because blown-in insulation can settle—leaving a space at top—it is important to check several feet down.

    With the wire hanger method, you can quite clearly hear the hanger tapping both ​sides of the wall. With the scope, it's visually obvious.