Vent Stack Height Above Roof

From any vertical surface the soil pipe also known as the vent stack or stack pipe provides air for the plumbing system.

Vent stack height above roof.

4 except for a fresh air inlet where a vent pipe is terminated in open air the terminal shall be located a not less than 1 000 mm above or not less than 3 5 m in any other direction from every air inlet openable window or door. Upc i 906 1 and 906 2. Extension of vent pipes through a roof shall be terminated not less than 12 inches above it. Offsets shall be permitted in the stack vent and shall be located at least 6 inches 152 mm above the flood level of the highest fixture and shall be in accordance with section p3104 5.

D where the buildingis 4 storeys or less in height the vent pipe terminates above the roof of the building. Plumbing code citations for plumbing vent or vent stack clearance distances. The slope is about 4 high for every 12 horizontal. Above the roof plumbing vent height.

Vent pipes should extend to outdoors above the building roof and should terminate vertically not less than 6 above the roof surface nor more than 24 and must be at least 12 from any vertical surface such as a nearby sidewall. 12 4 1 extension above roofs. Above the roof nor less than one 1 foot. A stack vent shall be installed for the waste stack.

Quoting the irc model plumbing code. Where a roof is to be used for any purpose other than weather protection the vent extensions shall be run at least seven feet above the roof. The size of the stack vent shall be not less than the size of the waste stack. Vents in these locations also should extend 610 mm 24 in above a roof.

Each vent pipe or stack shall extend through its flashing and shall terminate vertically not less than 6 inches 152 mm above the roof nor less than 1 foot 305 mm from a vertical surface. I have a main vent and a sink vent and both are only 6 high above the roof. Additionally vent pipes must be at least 305 mm 12 in away from a vertical surface. According to the uniform plumbing code the soil pipe or stack pipe shall extend vertically not less than six 6 inches.

The 6 you describe should be just fine. Vent pipes shall terminate not less than 6 inches above the roof measured from the highest point where the vent intersects the roof. I d maybe try to tie that existing 2 vent into your new 3.