22. July 2016

Thermal Paint: Don’t Believe the Hype

from Mike DeVries
Alton King's attic after being painted with insulating paint
Alton King’s attic after being painted with insulating paint (Photo from www.greenbuildingadvisor.com)

Recently with energy codes getting tougher and tougher, everyone is looking to come up with energy efficient ways to meet these codes. ASHRAE and IECC codes have been recommending continuous exterior insulation for a number of years and in the most recent versions have now made it a requirement.

CONTINUOUS INSULATION (ci). Insulating material that is continuous across all structural members without thermal bridges other than fasteners and service openings. It is installed on the interior or exterior or is integral to any opaque surface of the building envelope. – 2015 IECC – Section C201 General Definitions

Some products are making claims of energy efficiency that need to be looked at more closely – one such product is thermal paint.

The thermal paint industry states that the simple solution of applying two coats of thermal paint to a thickness of 110mills (2.8 millimeters or approximately 1/8”) will solve your thermal conductivity problems

To put this in perspective, this claim is suggesting that roughly 1/8” of an inch of protection is the same as placing the 4-6” of insulation in the walls above and below this exposed metal. You can probably start to see the challenge in putting belief in these claims.

To put a real world case to the above statement, a thermal paint salesman put his money where his mouth was and had his new house “insulated” with thermal paint because he believed that it would provide the thermal efficiency his company was stating.

The manufacturer claims that Super Therm (also spelled “Supertherm”) has an “R-19 equivalent rating” and “provides the same protection as 6 inches of fiberglass.”

The salesman instructed the builder to paint the inside of the house roof, attic floors, and walls with the thermal paint instead of using traditional insulation. To make a long story short…the thermal paint did not perform at all like the salesman and company documentation stated. The house HVAC system could not keep up with the virtually uninsulated house and during the summer, the upper floor was above 90 degrees with the air conditioning running full force.

(Read the full story on Green Builder Advisor’s webpage.)

Curt Freedman, a mechanical engineer, was asked to come out and determine why the house was not heating and cooling effectively.

…“After examining the entire system, Freedman evaluated the thermal insulation throughout the home,” wrote Justice Fields. “Based on his assessment, Freedman determined that the R-value of the Supertherm was essentially zero.” Freedman determined that the actual design heating load of the uninsulated house was 365,133 Btu/h, so it wasn’t any surprise that the 183,000 Btu/h boiler couldn’t keep up.

Freedman later wrote, “My report concluded that although some specific mechanical systems could be improved, the overwhelming and primary reason for the home being so cold was based simply on the fact that the original home has no effective insulation.”
An “Insulating” Paint Salesman is Tripped Up By His Own Product, Green Building Advisor

This case demonstrates that thermal paint cannot be compared to traditional insulation and should not be used as such. In summary, ask for verifiable proof when considering industry claims of effective energy solutions (such as using a thin layer of thermal paint), cannot replace traditional thermal structural breaks nor should they be considered as a solution to meet the requirements as outlined in IECC or ASHRAE.




Write comment

will be published
will not be published