How far must a vent terminate through a 12/12 slope?

The distance that a vent must terminate through a 12/12 slope is determined by the requirement for vent termination to ensure it is safe and effective in preventing any backflow or accumulation of gases. For a 12/12 slope, which is a pitch of 45 degrees, the vent must be positioned a minimum distance from the edge of the roofline to allow for proper ventilation and to keep the gases expelled from the system safely away from windows, doors, or any other openings.

In this case, a termination distance of 4 feet is appropriate as it facilitates adequate dispersion of gases and minimizes any potential hazards or foul odors that could occur if the vent is too close to occupied areas or air intake locations.

Using this specification also aligns with plumbing codes and regulations that govern the installation and termination of vent stacks in order to ensure safety and compliance within mechanical and plumbing systems.