Open Cell Spray Foam

ThermoSeal 500

Light density open cell spray foam insulation. Water blown with a GWP of 1, the lowest in the industry. IAPMO certified, air impermeable, and outstanding sound control.

Open CellR-4.1/inchGWP 1Water BlownIAPMO ER-0603Air Impermeable

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R-4.1

Per Inch (ASTM C 518)

100x

Expansion Ratio

0.75

Noise Reduction Coeff.

0.5 lb

Core Density (ft³)

Technical Specifications

ThermoSeal 500 Physical Properties

All values independently tested per ASTM standards. Full technical data sheet available for download.

Physical Properties (ASTM Tested)
R-Value	4.1 @ 1 inch	ASTM C 518
Core Density	0.5 lb/ft³	ASTM D 1622
Open Cell Content	> 97%	ASTM D 6226
Air Permeance	<0.02 L/sm² @ 75 Pa / 3.5"	ASTM E 283 & E 2178
Sound Transmission Coeff.	39	ASTM E 413
Noise Reduction Coeff.	0.75	ASTM C 423
Tensile Strength	5.19 PSI	ASTM D 1623
Compressive Strength	0.30 PSI	ASTM D 1621
Dimensional Stability	< 5%	ASTM D 2126
Flame Spread Index	< 25 (Class 1)	ASTM E 84
Smoke Developed Index	< 450	ASTM E 84

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Certifications & Compliance

Code Approvals

IAPMO ER-0603

Open cell spray foam: covers ThermoSeal 500 and 800 for residential and commercial applications per IRC/IBC/IECC.

Class 1 Fire Rating

Flame spread index <25 and smoke developed index <450 per ASTM E 84.

Air Impermeable

Meets air impermeable definition at 3.5 inches per ASTM E 283 / E 2178 (<0.02 L/sm² @ 75 Pa).

Zero ODP / GWP 1

Totally water blown: no HFC, no HCFC, no halogenated flame retardants. GWP of 1.

Other ThermoSeal Products

ThermoSeal 800

Open cell, R-4.5/inch, enhanced density

ThermoSeal HFO

Closed cell, R-7.4/inch, GWP 1

ThermoSeal 5G

Closed cell, commercial grade, NFPA 285

Where to Use It

ThermoSeal 500 Applications

Recommended applications for ThermoSeal 500 based on climate zone, building type, and performance requirements.

Interior Walls

Full cavity fill at 3.5 inches provides R-14.4 and complete air sealing. Superior sound control with NRC 0.75, ideal for party walls and home theaters.

Attics & Roofdecks

Applied to the underside of roof sheathing in warm and mixed climates (Zones 1–4) to create a sealed conditioned attic. At 5.5 inches delivers R-22.6.

Cathedral Ceilings

Full rafter cavity fill eliminates thermal bridging at framing members and seals the entire assembly against air movement.

Commercial Interiors

Cost-effective air sealing for large commercial cavities. Higher expansion ratio means more coverage per kit than denser products.

Basement Walls

Applied to above-grade interior basement walls in conditioned spaces for air sealing and thermal performance.

Sound Isolation

With an NRC of 0.75 and STC of 39, ThermoSeal 500 delivers the highest sound attenuation of any spray foam product in our lineup.

Common Questions

ThermoSeal 500 FAQ

What is the R-value of ThermoSeal 500?

ThermoSeal 500 delivers R-4.1 per inch as tested per ASTM C 518. At a full 3.5-inch wall cavity fill, the installed R-value is R-14.35. At 5.5 inches (rafter application), R-22.55.

Is ThermoSeal 500 air impermeable?

Yes. At 3.5 inches, ThermoSeal 500 meets the air impermeable threshold defined by IRC and IBC: less than 0.02 L/s·m² at 75 Pa per ASTM E 283 and E 2178. This qualifies it as the air barrier in the building assembly, eliminating the need for separate house wrap in many applications.

Does ThermoSeal 500 require an ignition barrier?

In most attic and crawlspace applications, building codes require an ignition barrier over open cell spray foam. Consult your local building official and the IAPMO ER-0603 evaluation report for specific assembly approvals in your jurisdiction.

What blowing agent does ThermoSeal 500 use?

ThermoSeal 500 is totally water blown, meaning water is the sole blowing agent. It contains no HFCs, no HCFCs, no halogenated flame retardants, and no ozone depleting substances. Its Global Warming Potential (GWP) is 1, the lowest possible.

Can ThermoSeal 500 be used in crawlspaces?

ThermoSeal 500 is suitable for above-grade interior crawlspace walls in conditioned crawlspace assemblies where moisture from soil contact is managed separately. For below-grade or high-moisture crawlspaces, ThermoSeal HFO or 5G closed cell foam is recommended.