Industrial insulation coatings are heat-reflective paints that installers use to coat pipes to reduce outward heat radiation. They are often promoted by manufacturers as a viable alternative to traditional insulations.
But the performance characteristics of coatings and traditional insulations are quite different. So the question is, what can third-party testing tell us about the comparative advantages and disadvantages of using thermal coatings versus traditional insulation products?
The ASTM C518 test method for evaluating the performance of traditional insulations such as calcium silicate and mineral wool doesn’t apply to thermal coatings because they are so thin that they require multiple layers in order to be thick enough to make an accurate comparison.
That is why a test method was developed by an accredited, independent laboratory at the request of the North American Insulation Manufacturers Association (NAIMA) in 2008. This test was later employed by the American Society of Heating Refrigeration and Air conditioning Engineers (ASHRAE) in 2013.
Both the NAIMA and ASHRAE studies compared the thermal measurements of a bare, un-insulated thermal pipe test assembly to an insulation coating applied to the surface of the pipe. By comparing the power input, end loss, heat flux and surface temperature of the bare pipe to the coated pipe measurements, an apparent thermal conductivity value was calculated.
Using the new test method, NAIMA compared two insulation coatings to half-inch thick fiber glass pipe insulation from 50ᴼF to 350ᴼF. ASHRAE tested three insulation coatings between 125ᴼF to 300ᴼF. The coatings consisted of either ceramic particles suspended in a white coating or nanoparticles suspended in a translucent coating. The coatings were applied under supervision by installers or by the company that sold the coating.
What, you ask, did the tests show? Read the new IIG Technical Bulletin (below) to find out.