The present invention concerns an automotive protective mat (1), also known as throw in mat or protective mat. This mat comprises a microporous stiffening layer (2) (acoustical membrane). This layer may be composed of several sheets. The overall air flow resistance is between 500 Ns/m³-4000 Ns/m³. It is essential for this mat (1) that it is hydrophobic. In order to achieve an enhanced acoustical effectiveness a decoupling layer (6) is foreseen between the microporous stiffening layer (2) and the vehicle floor (8). This decoupling layer might be incorporated in the mat (1) or constituted by the underlaying carpet or sound absorber of the vehicle floor. Further layers or sheets such as adhesive layers, non skid layers, face fabrics or carpets and/or loft layers can be added to the claimed mat.