A sealing gasket (4) for use between flashing members (31,32) is disclosed. It comprises a compressible sealing section and an attachment section comprising at least two legs configured for engagement with a flashing member, both sections extending over substantially the entire length of the sealing gasket. The at least two legs of the attachment section project from a base section of the attachment section so that a first recess and a second recess extending in parallel are defined, said first and second recesses being configured for engagement with a flange, ridge, or leg on a flashing member. The invention further relates to a flashing arrangement and to a method of sealing a gap between flashing members for a roof window.