A thermally insulative and waterproof barrier for protecting an exterior surface includes a plurality of generally rectangular flexible blankets in overlapping disposition. Each blanket defines a body and a peripheral margin about edges of the body, edges of the bodies of adjacent blankets (including the base layer) overlapping. Each body includes at least one base layer of thermal insulation and two cover layers of waterproof material. The cover layers are sealed together peripherally about the base layer to form the peripheral margin and exclude water from the base layer.