The Truth About R-Values What’s an R-Value?

R-Value is the measure of the ability of insulation material to resist heat transfer. The R-Value is determined by placing carefully prepared test specimens between two plates in a laboratory apparatus and measuring heat flow through the insulation. R-Value is a very accurate and reliable expression of how insulation materials perform with regard to conduction of energy in a laboratory apparatus.

But people don’t live in laboratories or only deal with the conduction of energy. They live in homes with real walls and ceilings, and in the real world of buildings R-Value is only one factor which determines the actual performance of insulated building assemblies. R-Values tell only part of the story.

R-Value is a laboratory measurement that measures conduction, but it does not effectively measure the other two methods of heat transfer: convection and radiation. So R-Value is only telling 1/3 of the story of how well your home will be insulated in real world conditions. R-Value is important, but building scientists know that focusing on R-Value to the exclusion of all other factors can result in disappointment.

It’s known, for instance, that thermal bridging can reduce the actual energy efficiency of a wall by up to 50 percent. U.S. scientists have proven that convective flows in very light density attic insulation can reduce its performance by more than 40 percent under winter conditions. Extensive and expensive air sealing measures must be used for fiber glass buildings to approach the tightness of buildings insulated with cellulose. The extra expense may yield few benefits. In a Massachusetts survey the cellulose insulated building still consumed 32% less energy for heating than buildings insulated with fiberglass, even after extensive air sealing of all the buildings was done.

The truth is…not all insulations effectively combat all three kinds of heat transfer. Unlike other insulations, Applegate Insulation effectively combats all three kinds of heat transfer. Applegate Insulation has an R-Value of 3.8, can be installed as a dense monolithic block in walls and as a blanket in the attic which helps to reduce air infiltration and acts as an effective barrier to heat transfer.

Whether your home was built a century ago or completed yesterday, it’s not too late for you to enjoy the benefits of Applegate Insulation.