SHIELD YOUR SYSTEM. SLASH YOUR ENERGY BILL.
ThermalBlock™
ThermalBlock™ is a unique thermal radiant barrier applied to the exterior cabinets of HVAC systems. ThermalBlock™ significantly reduces the thermal load from solar exposure, especially experienced by rooftop-mounted equipment like rooftop package units, exposed duct work, and rooftop air handlers.
93%
Solar Heat Blocked
30%
Increased HVAC Lifespan

Why Clients Love ThermalBlock™
01
Allows on-site application to both new and existing HVAC systems
02
Delivers considerable reductions in unit run-time, energy consumption, and utility bills
03
Is a green energy-savings solution that reduces your company’s carbon footprint
04
A one-and-done solution that will extend the life of the unit far beyond standard use
05
Delivers rapid ROI on a minimal capital investment
within 12-36 months
Block the Heat. Boost Performance.
When HVAC cabinets are exposed to direct sunlight, exterior temperatures can reach up to 180°F—even on mild days. As a result, this solar heat load drives up interior cabinet temperatures, making your HVAC unit work harder than it should.
The result? Increased run times, accelerated wear, more frequent repairs, and a shorter system lifespan.


How ThermalBlock™ Works
This is a is a high-performance radiant barrier coating designed to shield rooftop HVAC systems, exposed ductwork, and metal cabinets from solar heat. Applied directly to exterior surfaces, it reflects solar radiation before it can increase cabinet temperatures.
Once applied, ThermalBlock™ blocks up to 93% of solar heat, instantly reducing surface temperatures to within 10°F of the surrounding air—even in peak summer conditions.
Designed for Real-World Conditions
While HVAC units are tested in ARI-certified labs, they’re rarely evaluated under real rooftop heat-load conditions. In practice, most rooftop units operate under extreme solar exposure, which lab testing doesn’t reflect.
ThermalBlock™ bridges that gap—delivering performance in the environments your equipment actually faces.

Real Impact on Energy Use & Equipment Life
By keeping your cabinet cooler, our coating:
- Reduces HVAC run time, especially during high-demand periods
- Lowers energy consumption (kWh)
- Extends unit lifespan
- Reduces repairs and long-term maintenance costs
And since it can be applied on-site, it’s a smart, low-disruption upgrade for both new and existing systems.
Proven Results & Fast ROI
Extensive independent lab testing confirms the effectiveness of our coating. In real-world applications, customers often see:
- ROI in as little as 12-36 months
- Substantial energy savings
- A longer-lasting HVAC system
ThermalBlock™ Testing
ASTM C1549 Reflectivity Testing
Rating of .89 Achieved
This test places a sample in a light chamber and measures the percentage of visible light that is reflected off the surface. Thermax reflects 89% of visible light.
ASTM C1371 Emissivity Testing
Rating of .87 Achieved
This test places a sample in a chamber and measures it resistance to heat gain from heat sources of air temperature and IR heat gain. ThermalBlock™ rejects 87% of heat gain from external sources.
ANSI/UL 723 Flame and Smoke Spread
Flame Rating of 5, Smoke Rating of 20
This test used ThermalBlock™ applied to a cement board and then subjected to a metered flame at specified temperature and duration. With flame rating of 5 and smoke rating of 20, ThermalBlock™ is a tier 1 material and highly resistant to flame or heat.
Solar Reflective Index
Low Wind: 108.0
Medium Wind: 108.24
High Wind: 108.46
Achieved an SRI of 108 across varying wind conditions, indicating excellent solar reflectivity and heat resistance properties.
ASTM D882 Tensile strength
Rating of 5,374 psi
This test is conducted by using and prescribed thickness of ThermalBlock™ and applying a stretching pressure until the break point of the ThermalBlock™.
Formaldehyde Test
<10ppm
Measured formaldehyde levels were below 10ppm, confirming the coating’s safety for indoor air quality.
Volatile Organic Compounds (VOC) Test
12 Grams Per Liter
ThermalBlock™ has a very VOC level, aligning well with eco-friendly and indoor air quality standards, enhancing its appeal for residential and commercial markets.
ASTM D882 Elongation test
Rating of 30% Expansion/Contraction
This test was conducted by UL labs to determine the overall strength and the expansion and contraction abilities of the product. The results are excellent and show that ThermalBlock™ is a very durable product that will stand up over time.
NFRC 201-2017 SHGC Test
93% Reduction of Heat Transfer
Performed by Intertek Solar labs. Test showed a 83.63 w/m², 93% reduction of heat transfer through the coated surface and a SHGC improvement from .09 uncoated versus .01 for a coated surface.
Thermal Conductivity Test
K- Value: 13% Reduction
R-Value: 20% Increase
Test was conducted per ASTM C518-21, the coating reduced thermal conductivity by approximately 13%(K-Value) and increased thermal resistance by around 20%(R-Value) when applied to cement boards.
ASTM D3359 Adhesion Testing
Rating of 5A/5B
This test is conducted on a sample to determine how well it adheres to the surface and to determine the durability of the bond to the surface. 5A/5B are best in class ratings and are two tests conducted with an X cut on the surface and a cross hatch cut on the surface. With these results we have an extremely good bond and long life of Thermax bonded to a surface.
K-Value/
R-Value/U-Value
K-Value: 0.1775 W/mK
R-Value: 0.0485 m2K/W
U-Value: 21.37 W/m2K
The thermal conductivity (K-Value) of the cement board is 0.2048 W/mK, which improves to 0.1775 W/mK with ThermaBlock™. Correspondingly, the thermal resistance (R-Value) increases from 0.0405 m2K/W to 0.0485 m2K/W, indicating enhanced insulation. As a result, the thermal transmittance (U-Value) decreases from 24.69 W/m2K for the uncoated board to 21.37 W/m2K with the coating, demonstrating improved energy efficiency.
ASTM D3363 Pencil Hardness Test
Rating of 4B
This test is conducted on a coated sample by using specific pencils with varying lead hardness and the pencil is drawn across the surface to determine at what point it will scratch the surface. 4B is a mid range hardness and demonstrates resistance to medium traffic and abrasion.