Window or fresh air intake.
Vent pipe distance above roof.
New york state just raised plumbing vent pipe code from 12 inches to 18 inches above the roof and at least 10 feet horizontal distance from any opening to the building i e.
All other gas vents shall terminate not less than 2 feet 610 mm above the highest point where they pass through the roof and at least 2 feet 610 mm higher than any portion of a building within 10 feet 3048 mm.
Why plumbing air vents are important.
The re vent is the only exception since it runs horizontally.
Your home s plumbing system is designed to efficiently remove water and waste.
They may also see that the slope column references 1 4 inch per foot but they are likely to assume that it s just reiterating the minimum allowable slope for a 2 inch drain.
If the pipe is farther than 10 feet from the roof peak it must be 2 feet above the highest point of the roof within 10 feet.
It channels the exhaust gases to the vent and helps maintain proper atmospheric pressure in the waste system.
Above the roof plumbing vent height.
The vent stack is the pipe leading to the main roof vent.
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.
In other words the highest point within a 10 foot circle of the pipe.
When builders look only at the table without reading the text they find that a 2 inch diameter drain can run a maximum distance of 8 feet to the vent.
Its drainage and vent functions are actually two systems.
A note on the main drain.
However it needs to be at least six inches above your fixture s flood level to keep from getting wet.
On a sink that would be either the rim or overflow hole.