Yes. The answer is simple, so this could be the shortest blog ever. However, given the misinformation that is out there it is worth explaining why R-value is in fact a good measure of thermal performance and dispelling some common misconceptions about it.
What R-value considers and what it doesn鈥檛
We know that R-value measures resistance to heat flow, and there are three kinds of heat transfer to consider: conduction, convection and radiation. The FTC Rule on 鈥淟abeling and Advertising of Home 麻豆直播app鈥� requires the R-values of typical insulation materials be based on measurements taken using one of four approved ASTM test standards[1].听 These ASTM standards measure heat flux - which includes all three modes of heat transfer:听 conduction, convection and radiation.听听 Despite this, there are claims in the market that R-value only considers one type of heat flow, namely conduction. Martin Holladay, writing for Green Building Advisor back in 2009, recognized and sought to dispel this misinformation in a very thoughtful article on this subject. Fast forward to today, May of 2016, and this same misinformation is being propagated, this time in Spray Foam Magazine鈥檚 May-June edition, which contains an article again claiming R-value only considers conduction and not convection or radiation. Same claim, still false.