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:
|
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 |
|
| Autoclaved Aerated
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 |
