Insulating Your Floor

A lot of energy can leak through the floor, so it’s important to insulate correctly. For floors, use R-19 kraft-faced insulation in rolls or batts, or maximize your energy efficiency with R-21.

Kraft- or Foil-Faced Insulation with Vapor Retarder

This type of insulation has either a foil-backed facing or kraft paper layer attached. The attached facing layer helps control the amount of moisture vapor that passes through the insulation that could collect inside ceilings, exterior walls and floors. Kraft and foil facings are combustible and have to be covered with an approved interior finish (i.e., drywall).

Rolls

Rolls are long strips of insulation rolled into bales. You measure the length you need and cut it off with a utility knife. Rolls are best for covering large open areas, like attics and floors.

Batts

Batts are pre-cut lengths of fiberglass insulation. Batts are available unfaced, or with aluminum foil or paper facing.

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Measure the Area of your Floor

To determine the size of the area you are insulating, follow these steps:

1. Measure the length of the floor joists you want to insulate. Don’t forget to measure the width of the space between the joists (this will be either 15"–16" or 23"–24"), so you’re sure which products to choose.
2. Don’t forget to measure the width of the space between the wall studs (this will be approximately 14.5"), so you’re sure which products to choose.

3. Multiply the number of floor joists times the length of those joists:

   Example:

   5 Joists
   × 20 ft. Long
   = 100 sq. ft. of Floor Area

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The following products are recommended for use with floors:

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16 items found

Product	Coverage (ft.2)	Product Image	Quantity
Owens Corning EcoTouch™ R30 Kraft 8 ¼ in x 15 ½ in x 48 in Cathedral Batts in Bag Insulation R-30 Kraft-faced Insulated Batt. Batts are 48 inches long, 15 ½ inches wide, and 8 ¼ inches thick. Square feet = 67.81. Close Product Details Name: Owens Corning EcoTouch™ R30 Kraft 8 ¼ in x 15 ½ in x 48 in Cathedral Batts in Bag Insulation SKU: 592327 Length: 48.000 Width: 15.500 Coverage (ft2): 56.83 Thickness: 8.250 R-Value: 30.00 Description: R-30 Kraft-faced Insulated Batt. Batts are 48 inches long, 15 ½ inches wide, and 8 ¼ inches thick. Square feet = 67.81.	56.83
Owens Corning EcoTouch™ R30 Kraft 9 ½ in x 16 in x 48 in Batts in Bag Insulation R-30 Kraft-faced Insulated Batt. Batts are 93 inches long, 16 inches wide, and 9 ½ inches thick. Square feet = 56.83. Close Product Details Name: Owens Corning EcoTouch™ R30 Kraft 9 ½ in x 16 in x 48 in Batts in Bag Insulation SKU: 566974 Length: 48.000 Width: 16.000 Coverage (ft2): 56.83 Thickness: 9.500 R-Value: 30.00 Description: R-30 Kraft-faced Insulated Batt. Batts are 93 inches long, 16 inches wide, and 9 ½ inches thick. Square feet = 56.83. View This Product at The Home Depot	56.83
Owens Corning EcoTouch™ R30 Kraft 9 ½ in x 24 in x 48 in Batts in Bag Insulation R-30 Kraft-faced Insulated Batt. Batts are 93 inches long, 24 inches wide, and 9 ½ inches thick. Square feet = 80. Close Product Details Name: Owens Corning EcoTouch™ R30 Kraft 9 ½ in x 24 in x 48 in Batts in Bag Insulation SKU: 598484 Length: 48.000 Width: 24.000 Coverage (ft2): 80.00 Thickness: 9.500 R-Value: 30.00 Description: R-30 Kraft-faced Insulated Batt. Batts are 93 inches long, 24 inches wide, and 9 ½ inches thick. Square feet = 80. View This Product at The Home Depot	80.00
Owens Corning EcoTouch™ R30 Unfaced 9 ½ in x 24 in x 48 in Batts in Bag Insulation R-30 Unfaced Insulated Batt. Batts are 48 inches long, 24 inches wide, and 9 ½ inches thick. Square feet = 80. Close Product Details Name: Owens Corning EcoTouch™ R30 Unfaced 9 ½ in x 24 in x 48 in Batts in Bag Insulation SKU: 586103 Length: 48.000 Width: 24.000 Coverage (ft2): 80.00 Thickness: 9.500 R-Value: 30.00 Description: R-30 Unfaced Insulated Batt. Batts are 48 inches long, 24 inches wide, and 9 ½ inches thick. Square feet = 80.	80.00
Owens Corning EcoTouch™ R30 Unfaced 9 ½ x 15 in x 25 ft Continuous Roll Insulation R-30 Unfaced Insulated Roll. Rolls are 25 feet long, 15 inches wide, and 9 ½ inches thick. Square feet = 31.25. Close Product Details Name: Owens Corning EcoTouch™ R30 Unfaced 9 ½ x 15 in x 25 ft Continuous Roll Insulation SKU: 564987 Length: 25.000 Width: 15.000 Coverage (ft2): 31.25 Thickness: 9.500 R-Value: 30.00 Description: R-30 Unfaced Insulated Roll. Rolls are 25 feet long, 15 inches wide, and 9 ½ inches thick. Square feet = 31.25. View This Product at The Home Depot	31.25
Owens Corning EcoTouch™ R30 Unfaced 9 ½ x 23 in x 25 ft Continuous Roll Insulation R-30 Unfaced Insulated Roll. Rolls are 25 feet long, 23 inches wide, and 9 ½ inches thick. Square feet = 47.92. Close Product Details Name: Owens Corning EcoTouch™ R30 Unfaced 9 ½ x 23 in x 25 ft Continuous Roll Insulation SKU: 612706 Length: 25.000 Width: 23.000 Coverage (ft2): 47.92 Thickness: 9.500 R-Value: 30.00 Description: R-30 Unfaced Insulated Roll. Rolls are 25 feet long, 23 inches wide, and 9 ½ inches thick. Square feet = 47.92. View This Product at The Home Depot	47.92
Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 15 ¼ in x 93 in Batts in Bag Insulation R-19 Kraft-faced Insulated Batt. Batts are 93 inches long, 15 ¼ inches wide, and 6 ¼ inches thick. Square feet = 49.77. Close Product Details Name: Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 15 ¼ in x 93 in Batts in Bag Insulation SKU: 434823 Length: 93.000 Width: 15.250 Coverage (ft2): 49.77 Thickness: 6.250 R-Value: 19.00 Description: R-19 Kraft-faced Insulated Batt. Batts are 93 inches long, 15 ¼ inches wide, and 6 ¼ inches thick. Square feet = 49.77.	49.77
Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 15 in x 93 in Batts in Bag Insulation R-19 Kraft-faced Insulated Batt. Batts are 93 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 67.81. Close Product Details Name: Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 15 in x 93 in Batts in Bag Insulation SKU: 601829 Length: 93.000 Width: 15.000 Coverage (ft2): 67.81 Thickness: 6.250 R-Value: 19.00 Description: R-19 Kraft-faced Insulated Batt. Batts are 93 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 67.81. View This Product at The Home Depot	67.81
Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 19 ¼ in x 48 in Batts in Bag Insulation R-19 Kraft-faced Insulated Batt. Batts are 48 inches long, 19.25 inches wide, and 6 ¼ inches thick. Square feet = 51.33. Close Product Details Name: Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 19 ¼ in x 48 in Batts in Bag Insulation SKU: 560042 Length: 48.000 Width: 19.250 Coverage (ft2): 51.33 Thickness: 6.250 R-Value: 19.00 Description: R-19 Kraft-faced Insulated Batt. Batts are 48 inches long, 19.25 inches wide, and 6 ¼ inches thick. Square feet = 51.33.	51.33
Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 23 in x 93 in Batts in Bag Insulation R-19 Kraft-faced Insulated Batt. Batts are 93 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 118.83. Close Product Details Name: Owens Corning EcoTouch™ R19 Kraft 6 ¼ in x 23 in x 93 in Batts in Bag Insulation SKU: 591947 Length: 93.000 Width: 23.000 Coverage (ft2): 118.83 Thickness: 6.250 R-Value: 19.00 Description: R-19 Kraft-faced Insulated Batt. Batts are 93 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 118.83. View This Product at The Home Depot	118.83
Owens Corning EcoTouch™ R19 Kraft 6 ¼ x 15 in x 39 ft 2 in Continuous Roll Insulation R-19 Kraft-faced Insulated Roll. Rolls are 39 feet 2 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 48.96. Close Product Details Name: Owens Corning EcoTouch™ R19 Kraft 6 ¼ x 15 in x 39 ft 2 in Continuous Roll Insulation SKU: 608028 Length: 468.000 Width: 15.000 Coverage (ft2): 48.96 Thickness: 6.250 R-Value: 19.00 Description: R-19 Kraft-faced Insulated Roll. Rolls are 39 feet 2 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 48.96. View This Product at The Home Depot	48.96
Owens Corning EcoTouch™ R19 Kraft 6 ¼ x 23 in x 39 ft 2 in Continuous Roll Insulation R-19 Kraft-faced Insulated Roll. Rolls are 39 feet 2 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 74.75. Close Product Details Name: Owens Corning EcoTouch™ R19 Kraft 6 ¼ x 23 in x 39 ft 2 in Continuous Roll Insulation SKU: 538764 Length: 468.000 Width: 23.000 Coverage (ft2): 74.75 Thickness: 6.250 R-Value: 19.00 Description: R-19 Kraft-faced Insulated Roll. Rolls are 39 feet 2 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 74.75.	74.75
Owens Corning EcoTouch™ R19 Unfaced 6 ¼ in x 15 in x 93 in Batts in Bag Insulation R-19 Unfaced Insulated Batt. Batts are 93 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 48.96. Close Product Details Name: Owens Corning EcoTouch™ R19 Unfaced 6 ¼ in x 15 in x 93 in Batts in Bag Insulation SKU: 595103 Length: 93.000 Width: 15.000 Coverage (ft2): 48.96 Thickness: 6.250 R-Value: 19.00 Description: R-19 Unfaced Insulated Batt. Batts are 93 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 48.96. View This Product at The Home Depot	48.96
Owens Corning EcoTouch™ R19 Unfaced 6 ¼ in x 23 in x 93 in Batts in Bag Insulation R-19 Unfaced Insulated Batt. Batts are 93 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 75.07. Close Product Details Name: Owens Corning EcoTouch™ R19 Unfaced 6 ¼ in x 23 in x 93 in Batts in Bag Insulation SKU: 568825 Length: 93.000 Width: 23.000 Coverage (ft2): 75.07 Thickness: 6.250 R-Value: 19.00 Description: R-19 Unfaced Insulated Batt. Batts are 93 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 75.07.	75.07
Owens Corning EcoTouch™ R19 Unfaced 6 ¼ x 15 in x 39 ft 2 in Continuous Roll Insulation R-19 Unfaced Insulated Roll. Rolls are 39 feet 2 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 48.96. Close Product Details Name: Owens Corning EcoTouch™ R19 Unfaced 6 ¼ x 15 in x 39 ft 2 in Continuous Roll Insulation SKU: 543558 Length: 468.000 Width: 15.000 Coverage (ft2): 48.96 Thickness: 6.250 R-Value: 19.00 Description: R-19 Unfaced Insulated Roll. Rolls are 39 feet 2 inches long, 15 inches wide, and 6 ¼ inches thick. Square feet = 48.96.	48.96
Owens Corning EcoTouch™ R19 Unfaced 6 ¼ x 23 in x 39 ft 2 in Continuous Roll Insulation R-19 Kraft-faced Insulated Roll. Rolls are 39 feet 2 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 74.75. Close Product Details Name: Owens Corning EcoTouch™ R19 Unfaced 6 ¼ x 23 in x 39 ft 2 in Continuous Roll Insulation SKU: 565260 Length: 468.000 Width: 23.000 Coverage (ft2): 74.75 Thickness: 6.250 R-Value: 19.00 Description: R-19 Kraft-faced Insulated Roll. Rolls are 39 feet 2 inches long, 23 inches wide, and 6 ¼ inches thick. Square feet = 74.75.	74.75
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Installation Tips

• Caulk and seal around band joist and all other penetrations, such as plumbing, electrical lines, cable lines, and HVAC and dryer vents, to prevent air infiltration. Use continuous rolls in floors for seamless runs along the longer joist spans. When you need to cut your insulation:
  • Lay it on a board with the kraft or foil facing down.
  • Lay a straightedge over the area of insulation to be cut.
  • Press your straightedge down hard, and cut with a utility knife.
  • Use the straightedge as a guide to cut a straight line.
• Install insulation with the vapor retarder toward the warm side of the structure. In a vented crawlspace, the warm side is usually up, closest to the floor. Never leave faced insulation exposed. The facing on kraft- and foil-faced insulation will burn and must be installed in substantial contact with a floor construction.
• Install the insulation all the way back at the end of each joist run for complete coverage under the house. There will usually be a narrow joist space on the wall running parallel to the joist. Cut insulation to fit this space.
• Cut insulation to fit around water pipes and cross braces. Insulate around electrical wiring and junction boxes carefully. Compressing insulation reduces its R-value, so be sure to gently fit insulation around obstacles, leaving no gaps between insulation pieces.
• Use nylon banding or metal insulation supports to support the insulation.

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