Hi, Do I need to prime the underside of the subfloor before putting it down? and if so what do I prime it with? Between the floor joists I've put down two VCL membranes with wool insulation in between. The subfloor (22mm T&G plywood) will sit directly on top of the membrane screwed into the top of the floor joists and glued in the T&Gs. As I've added in membranes to control moisture and insulation to control temperature under the floor, will a primer/sealant be needed on the subfloor? Thanks in advance, Dan