Paul Fisette is a wood technologist and former director of the Building Materials Technology and Management program at the University of Massachussets in Amherst, Mass.
While preparing for an extensive remodeling project, we discovered that the housewrap was installed underneath the exterior 7/16-inch plywood rather than on top. According to the scope of work, we are supposed to install 1/2-inch foam board with taped seams over the entire exterior. Will the plywood sandwiched between the housewrap and foam cause a problem with moisture buildup or anything else?