R-value, U-value and Energy Efficiency

Everybody thinks “R-value” when they think about insulation.  Somehow, a myth has taken hold that more “R” will cure all ills - in fact, most people think that R-24 is twice as good as R-12.  As we shall see, that just isn’t so!  There is more to effective insulation than just piling on material.  In fact, an energy efficient building can be achieved with much lower R-values than we have been conditioned to believe.  The key is proper air sealing.  When you think about it, it is quite simple: if air can flow around your insulation, does it really matter how thick that insulation is?

The terminology used to describe insulation and energy efficiency can be confusing.  Here we attempt to de-mystify the terms and put some common sense into the debate.  Hopefully, when you are done reading you will find that it is not so mysterious after all!

Our examination consists of three brief parts:

What Exactly IS R-Value? explains and defines the term,

The R-value Myth discusses the several important factors that go into making an effective insulation system, and finally

How Much R-Value is Enough? provides a specific framework for answering just that question.