Installing Insulation Under The Floor

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Installing floor insulation will save you money on heating and cooling costs. If you live in an older home and notice that the floors are usually cold, then that cold air is radiating into the room. Your heating costs will be much higher during the colder seasons. When you install floor insulation it will protect your floor from moisture, and keep the cold air from reaching the floor.

Installation of floor insulation is a very straightforward process. If the house is new construction, or you are adding an addition, it is easily done before the subfloor goes down. If you live in an older home, then the process is a little trickier, but still easy to do.

Measure The Floor

With your tape measure, determine how much floor insulation you will need. Measure the width and length of the room and multiply them together to give you the square footage of the room. Take this with you when you order the insulation. You will also want to determine the R-factor of the insulation. The R-factor is the amount of insulation your home has. The higher the number, the more efficient it is. Insulation is also sold in rolled batts. If you know how many square feet you need, then you can simply purchase the appropriate number of rolls.

Install Insulation - New Construction

There are two ways to install floor insulation. If you are in a new home that does not have any flooring down yet, you can lay the insulation in between the exposed joists. Starting at one end of the room, work your way to the other corner. Fold out the paper flaps along the side of the insulation and staple them to the joist. Staple the insulation every six inches or so. Lay down the water barrier over the insulation and staple it to the joists.

Install Insulation - Basement

In an older home, the process is basically the same, but you will have to insulate below the floor in the basement or crawl space. Again, start in the corner of the room and unroll the insulation. You will have to lift up the insulation in between the joists and staples. Place metal supports on the joists to help hold the insulation up. Continue until you have completed the entire floor.

If you are remodeling your room in the near future, it would be better to wait until you tear up the floor to add the floor insulation. Once you get to the subfloor, pry it up to expose the joists and lay the insulation as you would in the first example. Reinstall the subfloor over the vapor barrier and finish with your floor remodel. Now when you walk out onto the floor in the dead of winter your feet will be warmer because of the floor insulation.