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How To Install Batt Insulation

To insulate a wall cavity you have pretty much two different ways to do it. You can either have someone spray foam it or you yourself can install batt style insulation. In this article I will explain to you how to install batt insulation or as sometimes referred to as fiberglass insulation.

Batt insulation comes in a few different widths and thicknesses. For width you need to know if you studs in the wall are spaced at 16" or 24" OC (on center). Now I realize that some spaces will be smaller than that regular size in different areas, but for those you will simply cut them narrower as needed. The next thing you need to know is how thick your wall cavity is to get the proper thickness of insulation or "R" value. So if your wall is a 2x4 wall you need R-12, if it is a 2x6 wall you need R-20.

The final thing you will need is to figure out how many square feet of insulation you need by taking the wall length in feet and the wall height in feet and multiplying them by each other.This total square footage number will let the person at your building centre know how much insulation you will need.

Tools Required

• Utility knife with sharp blades
• Tape measure
• 4 foot long straight edge
• Step ladder
• Dust mask

Materials Required

• Batt insulation

Fiberglass Batt Insulation Installation

TIP: Wear a dust mask while working with fiberglass insulation to keep the small dust from getting into your throat and lungs

Once you have everything you need and all necessary tasks in the wall cavity are completed like having the electrical all ran that you wanted, then it is time to start installing insulation.

Open a bag of insulation to get started. You will find many strips of insulation inside the bag all cut to size. For the main stud spaces these batts should be a perfect width to friction fit themselves in the space. Start by placing the first piece in a regular stud space and slide it in and to the top. You do not want it compacted too tight, but snug to the studs. Next in that same stud space measure up from the top of the bottom wall plate to the bottom of the upper piece of insulation you just installed. Now cut a new piece to that length plus 1" and install it below the first one. Easy right? So continue on and do all the regular sized spaces like that. If you come to a electrical box or something like that simply measure and cut out a chunk so that it fits around the object snugly.

Now you have all the regular spaces done but there are a few narrower spaces left to do likely. So measure these spaces and add 1/2" to the measurement, cut the insulation using your knife and straight edge and install just like before.

TIP: Packing the cavity with insulation too tightly will actually not allow it to insulate as well so remember to keep it just snug.

You are now ready to install a vapour barrier over your new insulated wall.