The Way to Insulate the Walls in an Older Home



Inadequate insulation in the exterior walls of your home wastes energy and forces your heating system to work extra hard. This shortens the life of your equipment and costs you in replacement and maintenance expenses over time. In addition, it leads to reduced comfort and chilly drafts that can affect your loved ones. With the addition of insulation into the walls of the older home, you’ll not just reduce your heating costs each month, but also extend the life of your heating system. And, if you’re thinking about putting your home on the market, up-to-date insulation is a powerful selling point.

Insulate Exposed Walls

Look for walls in your home which aren’t covered with drywall. Check the attic, basement, crawl spaces and garage. Often these walls remain bare, and will provide you a significant return as soon as they are insulated.

Assess the depth of the wall framing on these exposed partitions with your tape measure.

Describe how much insulation you’ll have to add in this space. The U.S. Department of Energy recommends using insulation that supplies at least R-13. Standard fiberglass batts provide R-3.2 per inch, while rigid foam ranges from R-4 to R-8 each inch. Decide which material you want to use based on the depth of your walls.

Cut the insulation to size using a utility knife. Cut every batt or sheet of cloth so that it fits snugly between the wall studs.

Put the insulation into the wall pit layer at a time. Attempt not to compress the layers against one another, as this reduces their insulating effectiveness.

Cover rigid foam insulation with 1/2-inch drywall or any other fire-rated substrate to meet the regional building codes. Fiberglass batts can be left exposed, while all rigid foam must be dealt with by an approved covering for security.

Insulate Finished Walls

Go to any unfinished area of your home, such as the attic or basement, and check the depth of the wall framing. You’ll likely have 4, 6, or 8 inch partitions depending on where you live and the way you are home was constructed.

Rent a foam insulation sprayer from your regional home improvement store.

Cut 1/2-inch holes on the inside side of your walls with your hole saw so you can inject the foam. Read the directions on the foam insulation carefully to determine how many holes you need and where they should be placed based on your own wall depth. Locate these holes in out-of-the way areas as far as possible, such as behind pieces of furniture.

Mix the spray foam with water according to the directions on the package. Pour the foam into the hopper on your sprayer.

Slide the tip of the nozzle on your sprayer into the holes that you drilled on your wall. Activate the sprayer to inject foam in the wall. Watch the pressure gauge carefully, and follow the directions on the foam packaging to determine the suggested levels of pressure.

Wait for the foam to dry and cut off any excess foam with a utility knife. Patch and sand the walls and end as desired.

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