membrane pare-eau/air

CONT: Housewrap, to stick with the most common material used as the liquid water control layer, is a material that can control the flow of liquid water as well as air. It's rarely installed well enough to be a good air barrier, but that's OK because in most homes it's stapled to a material that usually is: plywood or OSB [oriented strandboard]. Housewrap is the material. Controlling liquid water and air are the functions. The standard varieties don't control water vapor or heat.