Patented is a membrane product comprising a water impermeable membrane and a pressure sensitive, hot melt first adhesive adhered to one side of the water impermeable membrane. The first adhesive is in direct contact with at least a portion of the water impermeable membrane and is free of a curing additive. The first adhesive has a thickness of 0.004 to 0.015 inches. The membrane product is adhered to a portion of a building by the first adhesive. The membrane product is self adhering and the water impermeable membrane is the outermost layer of the membrane product relative to the building.