What type of cap or fitting should vent pipes terminate with?

Vent pipes should terminate with a weatherproof vent cap to ensure proper functioning and safety of the venting system. The primary purpose of vent pipes is to allow gases from the plumbing system to safely escape while preventing the entry of rainwater, debris, or animals that could clog or damage the vent. A weatherproof vent cap is specifically designed to provide an effective barrier against the elements. It allows air and gases to exit freely while keeping moisture and other foreign materials out, ensuring that the vent operates efficiently and does not impair the overall plumbing system.

Other types of fittings, such as a standard cap or an open vent, would not provide the necessary protection or functionality. A standard cap would completely seal off the vent, which would obstruct the release of gases, and an open vent, while it may allow gas to escape, does not offer any protection from environmental factors. A drain fitting is unrelated to venting as it serves a different purpose in the drainage system. Using a weatherproof vent cap is essential for maintaining a safe and efficient ventilation system in accordance with mechanical codes.