Lowe's Home Improvement
FREE PARCEL SHIPPING on Qualifying Orders

Install Insulation

Install Insulation

Make your home warmer in winter, cooler in summer and save yourself some money with proper insulation. With the right tools and materials, it isn't hard to install insulation yourself.

Tools & Materials

Use this checklist when you go to the store and purchase your items.


Selecting Insulation

r value map

Determine the R-value required in your area by using the map and chart. Insulation is available in rolls or batts.


Calculating R-value and Square Feet.
R value chart

Measure the distance between wall studs to determine whether you need 15-inch or 23-inch-wide insulation. Use our insulation calculator to determine how many square feet of insulation you need.




Install Roll Insulation

installing roll insulation

Roll insulation can be used anywhere in your home, although they are best for covering long unobstructed areas like attics and crawl spaces.

Roll insulation can be cut to fit any size cavity and are typically available in faced and unfaced. For a more comfortable installation with less itch and dust, look for a product which is poly-encapsulated, or wrapped in plastic. The plastic facing also serves as a vapor retarder. 

Faced insulation is used in exterior walls as well as attics, finished basements, ceilings, floors, knee walls and cathedral ceilings. Like other forms of insulation, rolls are available in a variety of R-values.

When choosing roll insulation, make sure you use the most appropriate R-value.


Step 1

Open the packages by cutting lengthwise through the side panel. Be careful to avoid cutting the product or facing. The insulation will quickly expand to its full volume when the bag is opened.


Step 2

Rolls must be measured and cut to fit into wall cavities. Cut insulation about an inch wider than the space using a sharp utility knife against a safe backstop, such as an unfinished floor or other smooth, flat surface. Always cut on the unfaced side of the batt.


Step 3

Cut the insulation to fit properly. Don't double it over or compress it. Compression changes the R-value of the insulation.


Step 4

Gently push insulation into the cavity so that it sits all the way, especially at the corner and edges. Then, fluff it to its full expansion by pulling it forward to fill the depth of the cavity. The fit should be snug.


Step 5

With faced insulation make sure the vapor retarder is facing the conditioned interior space, unless building codes specify otherwise.


Step 6

Allow friction to hold the insulation in place. Or you can staple the flanges of faced insulation to the insides or face of the joists. (Stapling on the inside is preferred by many drywallers because it leaves the edges of the framing members easier to locate. However, your local building codes may require you to overlap the flanges and staple them to the edges of the framing members.)


Step 7

Take care not to stretch the facing too tight as you staple, which can over compress the insulation, and avoid gaps and puckers.


Step 8

Secure floor insulation with wire fasteners. Press the fasteners so they bow up gently against the subflooring without compressing it. Space the fasteners at least six inches from each end of the batt and 12" - 24" apart.


Step 9

When installing rolls in an unfinished attic or other large open area, simply unroll the insulation in place.


Step 10

Wherever there are adjacent rolls, make sure they fit snugly together.



Install Insulation Batts

installing unsulation batt

Batts are pre-cut panels of insulation and are available in a variety of lengths, widths and R-values. Batt insulation is made to fit within most regular wall framing, which are usually spaced 12", 16", or 24" on center, and for either 8-ft. or 9-ft. high walls.

Batt insulation is available with and without facing. Faced batts are used in exterior walls as well as attics, finished basements, ceilings, floors, knee walls and cathedral ceilings. The facing material usually serves as a vapor retarder and makes handling and attachment easier to install. Factory-applied vapor retarder facings are generally made of paper.

Faced batts are attached to framing members by stapling through the flanges. Unfaced batts are installed between framing members but not attached, allowing friction to hold them in place.


Step 1

For ceiling and attic spaces, use batts of R-30 or R-38. In exterior walls R-13 to R-21 is commonly used, while in interior walls where insulation is used for sound control, R-11 is used most frequently.


Step 2

Open the packages by cutting lengthwise through the side panel. Be careful to avoid cutting the product or facing. The insulation will quickly expand to its full volume when the bag is opened.


Step 3

Gently push batts into the cavity so that it sits all the way in, especially at the corner and edges. Then, fluff it to its full expansion by pulling it forward to fill the depth of the cavity. The fit should be snug,


Step 4

With faced batts make sure the vapor retarder is facing the conditioned interior space, unless building codes specify otherwise.


Step 5

Allow friction to hold the batts in place. Or you can staple the flanges of faced batts to the inside or face of the joists. (Stapling on the inside is preferred by many drywallers because it leaves the edges of the framing members easier to locate. However, your local building codes may require you to overlap the flanges and staple them to the edges of the framing members.)


Step 6

Take care not to stretch the facing too tight as you staple, which can over compress the batt, and avoid gaps and puckers.


Step 7

Secure floor insulation with wire fasteners, sometimes called "lightning rods." Press the fasteners so they bow up gently against the subflooring without compressing it. Space the fasteners at least six inches from each end of the batt and 12" - 24" apart.


Step 8

Cut insulation about an inch wider than the space using a sharp utility knife against a safe backstop, such as an unfinished floor or other smooth, flat surface. Always cut on the unfaced side of the batt.


Step 9

For more ease of installation, look for batts that have vertical perforations at intervals along the width of the batt so cutting with a knife is not needed. Simply grip the insulation on either side of the perforations and tear to trim it to the desired width.


Step 10

For shorter spaces, cut the insulation to fit properly. Don't double it over or compress it. Compression changes the R-value of the insulation.


Step 11

If it takes more than one batt to fill the height of a wall cavity, make sure the two pieces are butted snugly together.