Doesn R-Value tell the whole story, i.e., Good R-Value equals good insulation.?
A.: You’ve hit upon perhaps the single most misunderstood idea about insulation, that R-Value tells the whole story. Not only does R-Value not tell the whole story, it barely scratches the surface. R-Value is a measure of a material’s thermal conduction, which is fine as far as it goes. Unfortunately, R-Value has taken hold in the consumer’s mind as a universal method for comparing insulations – the higher the R-Value, the better the insulation, end of story. But all R-Values are not created equal, because they measure only one of the factors that determine how an insulation product will perform in the real world. Insulation is, first and foremost, meant to stop the movement of heat. The problem with using R- Value as the sole yardstick of an insulation’s effectiveness is that heat moves in and out of your home or office in four ways: by conduction (which R-Value measures), and by convection, radiation and air infiltration (which R-Value doesn’t measure). But let’s stick with the conce
