What is the R-value and why do R-Control SIP structures outperform conventionally constructed homes with the same R-value?

ThermaFoam R-Control SIPs are manufactured in various thickness with values of R-15, R-23, R-30, R-37, and R-45.

The R-value of a material or wall assembly was not intended to be the measure of thermal efficiency of a home. R-value only measures resistance to heat loss by conduction. Other forms of heat loss are convection, radiation and especially infiltration (leakage). Conventional framing with batt insulation promotes convection, radiant and infiltration heat loss. Testing at Oak Ridge National Laboratories (ORNL) showed that ThermaFoam R-Control SIP walls are far superior to conventional stick frame and batt insulated walls. A 4-1/2” R-Control SIP panel was 45% better than 2×4’s with R-13 batt insulation and in fact was also better than 2×6’s with R-19 batt insulation.

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