Abstract: Provided is a nonwoven material as base interlining in sarking, roofing, or coated sealing membrane with an improved isotropy of the material. The nonwoven material comprises a spunbond nonwoven of polyester filaments. The nonwoven has a tensile strength ratio of the specific tensile strength MD to the specific tensile strength CD between 1 and 1.5. The nonwoven material for bituminous roofing membranes has a preferential thermal dimensional stability (TDS), as well as a preferential thermal shrinkage behaviour. Further, a method is provided to manufacture a nonwoven material with an improved mechanical homogeneity. In addition, a bituminous roofing product comprising a nonwoven material according to the invention is provided. The bituminous roofing product is preferably a bituminous roofing membrane.