For exposed interior applications, we use Thermax.

When it comes to exposed interior applications St. Croix Insulation uses Thermax Insulation/Finish Board. Thermax is durability allows it to withstand light to moderate impact. It is intended as an insulation and interior finish system for metal, wood post frame and concrete masonry buildings in manufacturing, mercantile, cold storage, warehouse, agriculture and other applications.

Thermax is a glass-fiber-reinforced polyisocynuarate foam core faced with a variety of facers. They are water tough and vapor resistant.

(see guide for the best product and facer to suit your application).

Thermax Heavy Duty

Nominal Board Thickness in. (mm)	Current R-value1	Current R-value2
.5 (12.7)	3.6	3.3
.75 (19.1)	5.4	5.0
1 (25.4)	7.2	6.5
1.25 (31.8)	9.0	8.0
1.55 (38.1)	10.8	10.0
1.75 (44.5)	12.6	11.4
2 (50.8)	14.4	13.0
2.5 (63.5)	18.0	15.8
3 (76.2)	21.6	19.0