THERMAX Heavy Duty
THERMAX™ Heavy Duty is a glass-fiber-reinforced polyisocyanurate foam core faced with nominal 4 mil embossed white acrylic-coated aluminum on one side and 1.25 mil embossed aluminum on the other side. Can be installed exposed to the interior without a thermal barrier.
Ease of application: Easy-to-handle THERMAX insulations require no special tools or materials for installation. Simply use a utility knife and a straight edge to cut the boards to size. Then adhere directly to basement walls with an approved adhesive.
For extra protection against air and moisture and a more finished appearance use one of the joint closure systems from Dow, or tape seams with THERMAX white foil tape or aluminum foil tape.
THERMAX insulations are backed with a 15-year limited thermal warranty.
| Nominal Board Thickness** |
R-Value† 3 |
Board Size |
Edge Treatment |
Min Compressive Strength† † |
| .5" |
3.3 |
48" x 96"/48" x 120" |
Square Edge |
25 psi |
| .75" |
5 |
48" x 96"/48" x 120" |
Square Edge |
25 psi |
| 1.0" |
6.5 |
48" x 96"/48" x 120" |
Square Edge |
25 psi |
| 1.5" |
9.8 |
48" x 96"/48" x 120" |
Square Edge |
25 psi |
| 2.0" |
13 |
48" x 96"/48" x 120" |
Square Edge |
25 psi |
| 2.5" |
15.8 |
48" x 96"/48" x 120" |
Square Edge |
25 psi |
| 3.0" |
19 |
48" x 96"/48" x 120" |
Square Edge |
25 psi |
Building Code Compliance Information
Complies with ASTM C 1289 Type I, Class 2. Meets IBC/IRC requirements for foam plastic insulation. See NER-681, UL 1256 — see UL Directory, FM 4880 — see Factory Mutual Approval Guide.
**Not all product sizes are available in all regions.
R means resistance to heat flow. The higher the R-value, the greater the insulating power. R-values are expressed in ft2 "h "°F/Btu.
†† Vertical compressive strength is measured at 10% deformation.
