R-value Testing of Insulated Siding
Because the performance of insulated siding is key to its qualification as home insulation, there are a number of regulations, standards and tests that determine how insulated siding is manufactured, tested and marketed. Insulated siding is a building product designed to reach higher levels of rigidity, dimensional stability and thermal performance through specific R-value testing. A product’s “R-value” is a measure of thermal resistance; the higher the R-value, the better the insulation’s effectiveness. For insulated siding, ASTM C1363 Standard Test Method for the Thermal Performance of Building Assemblies by Means of a Hot Box Apparatus is the standard used for determining the R-value of insulated siding.
VSI helped ASTM International, a standards-development organization, develop ASTM D7793, the standard specification for insulated siding.The standard includes requirements for both the vinyl siding and the foam plastic components, as well as performance requirements, including a minimum thermal resistance, or R-value,of at least R-2.0.
Learn more about how insulated siding can apply to current codes standards in Insulated Siding as Home Insulation: Guide for Users and Energy Raters.
This is an example of a cross section of a wood framed wall that has insulated siding with an R-value of 2.0 and R-11 cavity insulation. It exceeds the requirements of the 2009 IECC for Climate Zones 1 through 4 with a U-factor of .078.