Dow Roofing Systems – STYROFOAM™ Brand HIGHLOAD 40 Insulation

Available in United States and Canada

STYROFOAM™ Brand HIGHLOAD 40 Insulation has a minimum compressive strength of 40 psi (275 kPa). The Type VI extruded polystyrene foam insulation resists compressive creep and fatigue, delivering long-term compressive strength and thermal performance in high-load applications.

Building Code Compliance

Complies with ASTM C578 Type VI. Meets IBC/IRC requirements for foam plastic insulation. Meets CAN/ULC S701 Type 4. See ESR-2142, BOCA-ES RR 21-02. UL Classified, see Classification Certificate D369.

STYROFOAM™ Brand HIGHLOAD 40 Insulation CAD Details

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U.S. Commercial

STYROFOAM™ Brand HIGHLOAD™ 40 Insulation

With a minimum compressive strength of 40 psi, STYROFOAM™ Brand HIGHLOAD 40 Insulation is designed for high-load applications where long-term strength and thermal performance are required.

Related Information

STYROFOAM™ HIGHLOAD 40, 60 and 100 Extruded Polystyrene Insulation Product Information (143KB PDF)
20 Year Limited Warranty for Dow Roof Insulation in an American Hydrotech, Inc. Protected Membrane Roof Assembly (105KB PDF)

Nominal Board Thickness⁽¹⁾, in	R-Value⁽²⁾	Board Size, ft	Edge Treatment	Min Compressive Strength⁽³⁾, psi
2.0	10.0	2 x 8 / 4 x 8	Square Edge	40
3.0	15.0	2 x 8 / 4 x 8	Square Edge	40
⁽¹⁾ Not all product sizes are available in all regions. ⁽²⁾ 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. R-value determined by ASTM C518. ⁽³⁾ Vertical compressive strength is measured at 10% deformation (5% for STYROFOAM™ Brand HIGHLOAD 40, 60 and 100 Insulation products) or at yield, whichever occurs first. Since STYROFOAM™ Brand Extruded Polystyrene Foam and Dow polyisocyanurate insulation products are visco-elastic materials, adequate design safety factors should be used to prevent long-term creep. For static loads, 3:1 is suggested. For dynamic loads, 5:1 is suggested.

07 20 00 Board Insulation
07 21 13 Board Insulation (Below Grade)
07 22 16 Roof Board Insulation (Protected Membrane Systems)
07 55 00 Protected Membrane Roofing Insulation
31 23 24 Perimeter and Below-Grade Insulation

Canada Commercial

With a minimum compressive strength of 40 psi (275 kPa), STYROFOAM™ Brand HIGHLOAD 40 Insulation is designed for high-load applications where long-term strength and thermal performance are required.

Related Information

STYROFOAM™ HIGHLOAD 40, 60 and 100 Extruded Polystyrene Insulation Product Information (143KB PDF)
STYROFOAM™ Brand HIGHLOAD 40, 60 and 100 Extruded Polystyrene Insulation Product Information (French) (527KB PDF)
Tech Solutions 515.0 Achieving Canadian Class A Roof Assemblies Using STYROFOAM™ Brand Insulation With Single-Ply Membranes (164KB PDF)

Nominal Board Thickness⁽¹⁾, in	R-Value⁽²⁾ (RSI)	Board Size, ft (mm)	Edge Treatment	Min Compressive Strength⁽³⁾, psi (kPa)
1.0 (25)	5.0 (0.88)	2 x 8 (600 x 2400)	Butt Edge	40 (275)
1.5 (38)	7.5 (1.32)	2 x 8 (600 x 2400)	Butt Edge	40 (275)
2.0 (50)	10.0 (1.76)	2 x 8 (600 x 2400)	Butt Edge	40 (275)
3.0 (75)	15.0 (2.64)	2 x 8 (600 x 2400)	Butt Edge	40 (275)
⁽¹⁾ Not all product sizes are available in all regions. ⁽²⁾ R means resistance to heat flow. The higher the R-value or RSI (R-Value Système Internationale), the greater the insulating power. R-values are expressed in ft²•h•°F/Btu. RSI values are expressed in m²•°/W. R-value determined by ASTM C518. ⁽³⁾ Vertical compressive strength is measured at 10% deformation (5% for STYROFOAM™ Brand HIGHLOAD 40, 60 and 100 Insulation products) or at yield, whichever occurs first. Since STYROFOAM™ Brand Extruded Polystyrene Foam products are visco-elastic materials, adequate design safety factors should be used to prevent long-term creep. For static loads, 3:1 is suggested. For dynamic loads, 5:1 is suggested.