R-Value Table

Insulation Values For Selected Materials

Use the R-value table below to help you determine the R-value of your wall or ceiling assemblies. To obtain a wall or ceiling assembly R-value you must add the R-values of the individual components together. See the following example:

Wall Assembly R-Value (Example)

ComponentR-value
Wall - Outside Air Film0.17
Siding - Wood Bevel0.80
Plywood Sheathing - 1/2"0.63
3 1/2" Fiberglass Batt11.00
1/2" Drywall0.45
Inside Air Film0.68
Total Wall Assembly R-Value13.73

R-Value Table

MaterialR / InchR / Thickness
Insulation Materials
Fiberglass Batt3.14
Fiberglass Blown (attic)2.20
Fiberglass Blown (wall)3.20
Rock Wool Batt3.14
Rock Wool Blown (attic)3.10
Rock Wool Blown (wall)3.03
Cellulose Blown (attic)3.13
Cellulose Blown (wall)3.70
Vermiculite2.13
Air-entrained Concrete3.90
Urea terpolymer foam4.48
Rigid Fiberglass (> 4lb/ft3)4.00
Expanded Polystyrene (beadboard)4.00
Extruded Polystyrene5.00
Polyurethane (foamed-in-place)6.25
Polyisocyanurate (foil-faced)7.20
Construction Materials
Concrete Block 4"0.80
Concrete Block 8"1.11
Concrete Block 12"1.28
Brick 4" common0.80
Brick 4" face0.44
Poured Concrete0.08
Soft Wood Lumber1.25
  2" nominal (1 1/2")1.88
  2x4 (3 1/2")4.38
  2x6 (5 1/2")6.88
Cedar Logs and Lumber1.33
Sheathing Materials
Plywood1.25
  1/4"0.31
  3/8"0.47
  1/2"0.63
  5/8"0.77
  3/4"0.94
Fiberboard2.64
  1/2"1.32
  25/32"2.06
Fiberglass (3/4")3.00
  (1")4.00
  (1 1/2")6.00
Extruded Polystyrene (3/4")3.75
  (1")5.00
  (1 1/2")7.50
Foil-faced Polyisocyanurate (3/4")5.40
  (1")7.20
  (1 1/2")10.80
Siding Materials
Hardboard (1/2")0.34
Plywood (5/8")0.77
  (3/4")0.93
Wood Bevel Lapped0.80
Aluminum, Steel, Vinyl (hollow backed)0.61
  (w/ 1/2" Insulating board)1.80
Brick 4"0.44
Interior Finish Materials
Gypsum Board (drywall 1/2")0.45
  (5/8")0.56
Paneling (3/8")0.47
Flooring Materials
Plywood1.25
  (3/4")0.93
Particle Board (underlayment)1.31
  (5/8")0.82
Hardwood Flooring0.91
  (3/4")0.68
Tile, Linoleum0.05
Carpet (fibrous pad)2.08
  (rubber pad)1.23
Roofing Materials
Asphalt Shingles0.44
Wood Shingles0.97
Windows
Single Glass0.91
  w/storm2.00
Double insulating glass (3/16" air space)1.61
  (1/4" air space)1.69
  (1/2" air space)2.04
  (3/4" air space)2.38
  (1/2" w/ Low-E 0.20)3.13
  (w/ suspended film)2.77
  (w/ 2 suspended films)3.85
  (w/ suspended film and low-E)4.05
Triple insulating glass (1/4" air spaces)2.56
  (1/2" air spaces)3.23
Addition for tight fitting drapes or shades, or closed blinds0.29
Doors
Wood Hollow Core Flush (1 3/4")2.17
Solid Core Flush (1 3/4")3.03
Solid Core Flush (2 1/4")3.70
Panel Door w/ 7/16" Panels (1 3/4")1.85
Storm Door (wood 50% glass)1.25
  (metal)1.00
Metal Insulating (2" w/ urethane)15.00
Air Films
Interior Ceiling0.61
Interior Wall0.68
Exterior0.17
Air Spaces
1/2" to 4" approximately1.00