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.
********
This method ‘Wall Assembly
R-Value” gives incorrect results for MASS walls such as the All Wall
System.
Example
of error, as defined by ORNL research papers.
When compared to a 6” R-20 framed Wood Wall a
Foam Block (ICF) wall performed with a 9% better Energy Savings.
A wall built like All Wall performed with an 18%
better Energy Savings. (9% over the Foam Block walls) because of the concrete being in
direct contact with the interior.
See ORNL’s report
conclusions by clicking here. Oakridge National Laboratory
********
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 |
|
Material |
R/ |
R/ |
|
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 |
|
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 |
|
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 |
|
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 |
|
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 |
|
2.17 |
|
Solid Core Flush (1 3/4") |
|
3.03 |
|
Solid Core Flush (2 1/4") |
|
3.70 |
|
Panel Door w/ 7/16"
Panels |
|
1.85 |
|
Storm Door (wood 50% glass) |
|
1.25 |
|
(metal) |
|
1.00 |
|
Metal Insulating |
|
15.00 |
|
Air Films |
||
|
Interior Ceiling |
|
0.61 |
|
Interior Wall |
|
0.68 |
|
Exterior |
|
0.17 |
|
Air Spaces |
||
|
1/2" to 4" approximately |
|
1.00 |