
Wood Structural Panel R-values
Oriented Strand Board (OSB)
The thermal resistance, or R-value (in ft2 - hr - °F / BTU), of OSB panels is listed below. Thicker panels have more insulating value; therefore R-values increase with increasing panel thickness. These values are listed in Table 2 of the Structural Board Association's "OSB in Wood Frame Construction," (U.S. Edition 1996/97).
OSB Thickness (inch) | R-value |
---|---|
3/8 | 0.45 |
7/16 | 0.51 |
1/2 | 0.62 |
5/8 | 0.74 |
3/4 | 0.91 |
Plywood
The thermal resistance, or R-value (in ft2 - hr - °F / BTU), of plywood panels is listed below. Thicker panels have more insulating value; therefore R-values increase with increasing panel thickness. These values are listed in Chapter 25, Table 4 of the 2001 ASHRAE Handbook published by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE).
Plywood Thickness (inch) | R-value |
---|---|
1/4 | 0.31 |
3/8 | 0.47 |
15/32 | 0.59 |
1/2 | 0.62 |
19/32 | 0.74 |
5/8 | 0.78 |
23/32 | 0.90 |
3/4 | 0.94 |
7/8 | 1.09 |
1 | 1.25 |
1-1/8 | 1.41 |
