A contact layer used in waterproofing and roofing applications. The contact layer includes a mineral binder component B, thermoplastic polymer component P, and a surfactant component S. Also, a method for producing the contact layer, a method for binding two substrates to each other, a method for waterproofing a substrate, a waterproofed structure, a method for sealing a substrate against water penetration, a sealed construction for sealing a substrate against water penetration and a use of the contact layer as a waterproofing membrane.