Abstract: A venting system for structures using a ridge vent for venting a conventional exhaust system associated with a structure through a conventional ridge vent. The venting system includes a ridge vent adaptor, which defines a mounting head at an upper end, and a pipe coupling at a lower end. The mounting head is configured to be received through an opening formed in the ridge of the roof. The mounting head defines two mounting flaps for securing the ridge vent adaptor to the roof of the structure. The mounting flaps are dimensioned to be concealed by the ridge vent when installed. The pipe coupling is provided for coupling a conventional pipe of an exhaust system into the ridge vent adaptor. A transition portion is defined between the mounting head and the pipe coupling, and is continuously increasing in cross-sectional area from the pipe coupling to the mounting head such that outlet of exhaust gases is not inhibited.