Where can the vent stack terminate?

The vent stack should terminate in a manner that ensures the effective ventilation of the plumbing system and the safe discharge of sewer gases. This is why the correct answer indicates that the vent stack can legally terminate full size through the roof, connect to a vent header, or connect to the stack vent above the highest fixture.

Terminating the vent stack through the roof is the most common practice, as it helps to release gases above the structure and minimizes the risk of odors entering the building. Connecting to a vent header allows for integration with other venting systems, ensuring that multiple fixtures can share a common venting source. Additionally, connecting to the stack vent above the highest fixture is critical because it maintains proper air pressure and flow within the plumbing system, preventing issues such as negative pressure that could lead to siphoning of traps and subsequent odors or contamination.

This proper termination also adheres to plumbing codes designed to ensure safety and functionality, reinforcing the importance of correct installation practices in the plumbing design.