Open Cell Spray Foam

ThermoSeal 800

Enhanced density open cell spray foam. Higher density than standard open cell products delivers a stronger air barrier, superior sound control, and greater dimensional stability, all with a GWP of 1.

Open CellR-4.5/inch0.75 lb/ft³Water BlownIAPMO ER-0603Zero ODP

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R-4.5

Per Inch (ASTM C 518)

75x

Expansion Ratio

0.65

Noise Reduction Coeff.

0.75 lb

Core Density (ft³)

Technical Specifications

ThermoSeal 800 Physical Properties

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

Physical Properties (ASTM Tested)
R-Value	4.5 @ 1 inch	ASTM C 518
Core Density	0.75 lb/ft³	ASTM D 1622
Open Cell Content	> 75%	ASTM D 6226
Air Permeance	<0.02 L/sm² @ 75 Pa / 3.5"	ASTM E 283 & E 2178
Sound Transmission Coeff.	38	ASTM E 413
Noise Reduction Coeff.	0.65	ASTM C 423
Tensile Strength	5.7 PSI	ASTM D 1623
Dimensional Stability	< 3.15%	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

Covers ThermoSeal 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 threshold at 3.5 inches per ASTM E 283 / E 2178.

Zero ODP / Zero HFC

Totally water blown. No ozone depleting substances, no HFC blowing agents.

Other ThermoSeal Products

ThermoSeal 500

Open cell, R-4.1/inch, 0.5 lb/ft³

ThermoSeal HFO

Closed cell, R-7.4/inch, GWP 1

ThermoSeal 5G

Closed cell, commercial grade, NFPA 285

Where to Use It

ThermoSeal 800 Applications

Recommended applications for ThermoSeal 800 based on climate zone, building type, and performance requirements.

Walls: Premium Air Barrier

At 0.75 lb/ft³, ThermoSeal 800 provides a denser, more robust air barrier in wall cavities than standard 0.5 lb foam, preferred for high-performance and passive house projects.

Attics & Roofdecks

Applied to the underside of roof sheathing in warm and mixed climates. At 5.5 inches delivers R-24.6, slightly higher than ThermoSeal 500 at equivalent thickness.

Commercial Sound Isolation

STC 38 and NRC 0.65 make ThermoSeal 800 effective for offices, hotels, multi-family buildings, and any application where sound transmission control is a priority.

High-Performance New Construction

The enhanced density and dimensional stability of ThermoSeal 800 make it the preferred open cell choice for net-zero, LEED, and Passive House projects.

Retrofit: Existing Walls

Dense enough to be applied into closed wall cavities via injection in retrofit applications, filling the void without excessive pressure on the wall surface.

Cathedral Ceilings

Full rafter cavity fill with ThermoSeal 800 at 5.5 inches delivers R-24.6 with a Class 1 fire rating and complete air sealing.

Common Questions

ThermoSeal 800 FAQ

What is the difference between ThermoSeal 500 and ThermoSeal 800?

Both are open cell, water-blown spray foams with IAPMO ER-0603 certification. ThermoSeal 800 is 50% denser (0.75 vs 0.5 lb/ft³), delivers slightly higher R-value per inch (4.5 vs 4.1), and has better dimensional stability (<3.15% vs <5%). ThermoSeal 800 is preferred for high-performance projects where the extra density and stability are worth the modest additional cost.

What is the R-value of ThermoSeal 800?

ThermoSeal 800 delivers R-4.5 per inch per ASTM C 518. At a full 3.5-inch wall cavity fill, the installed R-value is R-15.7. At 5.5 inches, R-24.6.

Is ThermoSeal 800 suitable for sound isolation?

Yes. With an STC of 38 and NRC of 0.65, ThermoSeal 800 significantly outperforms fiberglass batts for sound control. It is well-suited for party walls, home theaters, hotel rooms, office partitions, and multi-family applications.

What blowing agent does ThermoSeal 800 use?

ThermoSeal 800 is totally water blown with zero HFCs, zero HCFCs, and zero ozone depleting substances. GWP of 1.

Does ThermoSeal 800 require an ignition barrier in attics?

In most jurisdictions, yes. Open cell spray foam in attics and crawlspaces requires an ignition barrier. Consult IAPMO ER-0603 and your local building official for specific assembly approvals.