A sealing device including a waterproofing layer, a functional layer, and a reinforcement layer fully embedded into the waterproofing layer or located between the waterproofing layer and the functional layer and/or a second waterproofing layer located on the outward facing side of the waterproofing layer opposite the side of the functional layer. Further, a method for producing a sealing device, to a method for waterproofing a substrate using one or more sealing devices, and to a roof system comprising a roof substrate and a sealing device directly adhered to the surface of the roof substrate with a layer of adhesive.