E-Star: Advancing Energy Efficiency in Housing

Energy Saving
Calculations

Homeowners and
Homebuyers
Builders Energy
Raters
Real Estate
Professionals
Code Officials Utilities
 

R-Value Table

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

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-Values of Materials

Material R/
Inch
R/
Thickness
Material R/
Inch
R/
Thickness
Insulation Materials Interior Finish Materials
Fiberglass Batt 3.14   Gypsum Board (drywall 1/2")   0.45
Fiberglass Blown (attic) 2.20      (5/8")   0.56
Fiberglass Blown (wall) 3.20   Paneling (3/8")   0.47
Rock Wool Batt 3.14   Flooring Materials
Rock Wool Blown (attic) 3.10   Plywood 1.25  
Rock Wool Blown (wall) 3.03      (3/4")   0.93
Cellulose Blown (attic) 3.13   Particle Board (underlayment) 1.31  
Cellulose Blown (wall) 3.70      (5/8")   0.82
Vermiculite 2.13   Hardwood Flooring 0.91  
Air-entrained Concrete 3.90      (3/4")   0.68
Urea terpolymer foam 4.48   Tile, Linoleum   0.05
Rigid Fiberglass (> 4lb/ft3) 4.00   Carpet (fibrous pad)   2.08
Expanded Polystyrene (beadboard) 4.00      (rubber pad)   1.23
Extruded Polystyrene 5.00   Roofing Materials
Polyurethane (foamed-in-place) 6.25   Asphalt Shingles   0.44
Polyisocyanurate (foil-faced) 7.20   Wood Shingles   0.97
Construction Materials Windows
Concrete Block 4"   0.80 Single Glass   0.91
Concrete Block 8"   1.11    w/storm   2.00
Concrete Block 12"   1.28 Double insulating glass
   (3/16") air space
  1.61
Brick 4" common   0.80    (1/4" air space)   1.69
Brick 4" face   0.44    (1/2" air space)   2.04
Poured Concrete 0.08      (3/4" air space)   2.38
Soft Wood Lumber 1.25      (1/2" w/ Low-E 0.20)   3.13
   2" nominal (1 1/2")   1.88    (w/ suspended film)   2.77
   2x4 (3 1/2")   4.38    (w/ 2 suspended films)   3.85
   2x6 (5 1/2")   6.88    (w/ suspended film and low-E)   4.05
Cedar Logs and Lumber 1.33   Triple insulating glass
   (1/4" air spaces)
  2.56
Sheathing Materials    (1/2" air spaces)   3.23
Plywood 1.25   Addition for tight fitting drapes or shades, or closed blinds   0.29
   1/4"   0.31 Doors
   3/8"   0.47 Wood Hollow Core Flush 
   (1 3/4")
  2.17
   1/2"   0.63    Solid Core Flush (1 3/4")   3.03
   5/8"   0.77    Solid Core Flush (2 1/4")   3.70
   3/4"   0.94    Panel Door w/ 7/16" Panels 
   (1 3/4")
  1.85
Fiberboard 2.64   Storm Door (wood 50% glass)   1.25
   1/2"   1.32    (metal)   1.00
   25/32"   2.06 Metal Insulating 
   (2" w/ urethane)
  15.00
Fiberglass (3/4")   3.00 Air Films
   (1")   4.00 Interior Ceiling   0.61
   (1 1/2") 6.00 Interior Wall   0.68
Extruded Polystyrene (3/4")   3.75 Exterior   0.17
   (1")   5.00 Air Spaces
   (1 1/2")   7.50 1/2" to 4" approximately   1.00
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

 


E-Star™ Colorado
E-Star Home | Colorado Home Performance with ENERGY STAR | Return to Top