With the rise in popularity of radiant barrier insulation, there has been an influx of products marketed under the term radiant barrier paint that are designed to be sprayed on the underside of the roof decking in the attic. These so called radiant barrier spray products are merely paint solutions with added metallic flakes designed to reflect heat and are NOT true radiant barriers per the radiant barrier definition set forth by the American Society of Testing and Materials International (ASTM) which governs the testing standards of building materials.
ASTM Radiant Barrier Definition : a product must have a low emittance of 10% or less and high reflectance of 90% or more to be classified as a "radiant barrier."
Our RadiantGUARD® Ultima-foil radiant barrier insulation products have an emittance of 3% and a reflectance of 97%; far exceeding the ASTM's radiant barrier minimum classification requirements.
More accurately, such radiant barrier spray products are classified as Interior Radiant Control Coatings IF they are tested by ASTM C1321 "Standard Practice for Installation and Use of Interior Radiation Control Coating Systems in Building Systems" and pass the minimum reflectance of 75%.
In 2006, David W. Yarbrough, Phd, PE conducted testing of the reflectivity properties of leading reflective paints. He found that the reflectivity of these radiant barrier paints varies widely. In fact, ONLY FOUR of the products tested actually passed the ASTM minimum requirements to even be classified as an IRCC intended to reduce heat trasfer, yet alone the requirements or a radiant barrier.
Details of the findings can be found in Dr. Yarbrough's heat reflective paint study.
|Product||Manufacturer/Distributor||Reflectivity||Radiant Barrier Paint?||IRCC?|
|Formula A Barrier Coat #85||Hy-Tech||34%||NO|
|Formula B Barrier Coat #85||30%||NO|
|Barrier Coat #233||11%||NO|
|HeatShield R-20||Kwik Co.||10%||NO|
|Radiosity 3000||Green Building Supply||11%||NO|
|Heat Bloc 75||STS Coatings, Inc.||78%||NO||YES|
|Lo/Mit-1||Solec-Solar Energy Corp||77%||NO||YES|
|Insuladd-White on RBC||14%||NO|
|Therma-Guard White||United Community Services of America||14%||NO|
|Therma-Guard White on Silver||15%||NO|
As can be seen above, the best spray on radiant barrier products are HeatBLOCK Ultra and LoMit-II Max. When installed correctly by a commercial contractor, these radiant barrier sprays can block between 80-85% of the radiant heat. But installing a radiant barrier spray solution is not an easy task for a do-it-yourself-er. In fact, getting expected results from a reflective paint requires the following:
Along with the fact that it's important to apply radiant barrier paints correctly, the installation of spray on radiant barriers are also best left to the commercial contractor for the following reasons:
Our RadiantGUARD® Ultima-foil radiant barrier reflects 97% of the radiant heat making them FAR SUPERIOR to any heat reflective paint and are much easier to install than a radiant barrier spray making the installation an easy DIY job.
Additionally, RadiantGUARD radiant barriers provide a quicker ROI (return-on-investment) because they block much more heat than the radiant barrier spray products and cost less to install because they don't require any special clothing or equipment and can be installed by the homeowner.
View and purchase our radiant barrier insulation.