Let's not lose sight of the fact that those R-value factors that most houses "achieve" are only done in a theoretical fashion. Far too few of the buildings that rely on a multilayer system of construction take care that each layer is applied well... which results in a cascade of problems down the road. A conventional, stick-framed house relies on a coalition of components, each part addressing one issue. White pine 2x provides the structure. It does not provide a moisture barrier, nor answer any aesthetic desires. Each need requires yet another material. Another step.

Problems arise in stick-frame construction when one of those materials has to juggle multiple jobs. A small chink exposing the whole to failure. The only way to prevent those small chinks is to not tolerate any mistakes throughout construction. Something's got to give folks. At the very least, we need to build multilayer systems with far fewer mistakes. But who wants to aim for the lowest mark? Let's begin setting our sights higher. Let's begin building better. Begin building with materials that address multiple issues at once.