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. 

 

Wall Assembly R-Value Example:

Component

R-value

Wall - Outside Air Film

0.17

Siding - Wood Bevel

0.80

Plywood Sheathing - 1/2"

0.63

3 1/2" Fiberglass Batt

11.00

1/2" Drywall

0.45

Inside Air Film

0.68

Total Wall Assembly R-Value

13.73

R-Value Table

Material

R/          
Inch        

R/
Thickness

Insulation Materials

Fiberglass Batt

3.14  

 

Fiberglass Blown (attic)

2.20

 

Fiberglass Blown (wall)

3.20

 

Rock Wool Batt

3.14

 

Rock Wool Blown (attic)

3.10

 

Rock Wool Blown (wall)

3.03

 

Cellulose Blown (attic)

3.13

 

Cellulose Blown (wall)

3.70

 

Vermiculite

2.13

 

Air-entrained Concrete

3.90

 

Urea terpolymer foam

4.48

 

Rigid Fiberglass (> 4lb/ft3)

4.00

 

Expanded Polystyrene (beadboard)

4.00

 

Extruded Polystyrene

5.00

 

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" common

 

0.80

Brick 4" face

 

0.44

Poured Concrete

0.08

 

Soft Wood Lumber

1.25

 

   2" nominal (1 1/2")

 

1.88

   2x4 (3 1/2")

 

4.38

   2x6 (5 1/2")

 

6.88

Cedar Logs and Lumber

1.33

 

Sheathing Materials

Plywood

1.25

 

   1/4"

 

0.31

   3/8"

 

0.47

   1/2"

 

0.63

   5/8"

 

0.77

   3/4"

 

0.94

Fiberboard

2.64

 

   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 Lapped

 

0.80

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

Plywood

1.25

 

   (3/4")

 

0.93

Particle Board (underlayment)

1.31

 

   (5/8")

 

0.82

Hardwood Flooring

0.91

 

   (3/4")

 

0.68

Tile, Linoleum

 

0.05

Carpet (fibrous pad)

 

2.08

   (rubber pad)

 

1.23

Roofing Materials

Asphalt Shingles

 

0.44

Wood Shingles

 

0.97

Windows

Single Glass

 

0.91

   w/storm

 

2.00

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 blinds

 

0.29

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 Ceiling

 

0.61

Interior Wall

 

0.68

Exterior

 

0.17

Air Spaces

1/2" to 4" approximately

 

1.00