Vent Exterior Terminations

Vent Height Above Roof
1. Extend vent pipes above the roof at least (≥) 6 inches, or the number of inches required by local snow accumulation and temperature conditions, whichever is higher. Measure height on the high side where the vent exits the roof. Obtain the snow accumulation height from the local building official.
2. Extend vent pipes at least (≥) 7 feet above any roof used as a balcony, observation deck, or similar accessible walking surface.

Vent Freezing and Frost Closure Protection
1. Protect exterior vent terminals from freezing by using heat, insulation or both.
2. Increase the diameter of exterior vent terminal pipes to at least (≥) 3 inches, beginning at least (≥) 1 foot below the roof or inside the wall.
3. These provisions apply only where the 97.5 percent winter design temperature is less than (<) 0° F. Obtain this information from IRC Chapter 3 and from the local building official.

Vent Flashing
1. Use approved fl ashing to make vent pipes extending through a roof water tight.
2. Use caulk to make vent pipes extending through a wall water tight.

Vent Prohibited Uses
1. Do not use a vent pipe to support flag poles, antennae, or similar components.
2. Do not use plumbing vents other than for venting the plumbing system (P3101.3). Example: do not discharge HVAC system condensate or waste water from a water softener or water filtration system into a vent pipe.

Vent Exterior Termination Locations
1. Locate plumbing vent terminations at least (≥) 4 feet below, or at least (≥) 3 feet above, or at least (≥) 10 feet horizontally from any:
(a) door or operable window, and                                                                                                                                                                                                                                                                                                                                                       (b) other air intake opening of the building, and
(c) air intake opening of any adjacent building.
2. Locate plumbing vent terminations running through a sidewall at least (≥) 10 feet from the lot line and at least (≥) 10 feet above the highest grade within 10 feet horizontally from the vent termination.
3. Protect side wall vent terminations from entry by birds or rodents.
4. Do not locate vent terminations directly under the building’s overhang if the overhang contains eave vents.