A cover board composite for overlying insulation of a roofing system includes a high-density core layer that is at least predominantly of a polymer material, a facer overlying and bonded to a bottom major surface of the core layer, and a reinforcement interposed between the facer and the bottom major surface of the core layer to coincide with a fastener pattern for securing the cover board composite to a roof deck and increase a per-fastener wind-uplift pull through rating for the cover board composite.