RR-0106: Problems with Housewraps

The primary function of a housewrap or building paper is rain penetration control. It is not air infiltration despite what the manufacturers say. The energy aspects of housewraps are vastly overstated. They have been embraced by builders for this function as can be evidenced by their market penetration. Yet their critical role in building durability is under appreciated and not marketed. It has been a triumph of marketing over physics.