Plumbing ?

[garrett]

How far from a vent stack can the kitchen drain be located?
Thank you,
Garrett

[Jerry Peck - Codeman]

The answer depends on the size of the pipe from the trap to the vent, the pipe is required to slope 1/4 inch per foot for 2 inches and smaller, which means smaller pipe must be shorter in length to allow the pipe to remain open and vented.
- 1-1/2 inch pipe is allowed to have a maximum distance of 6 feet from the weir of the trap to the vent.
- 2 inch pipe is allowed to have a maximum distance of 8 feet from the weir of the trap to the vent.

3 inch and 4 inch pipe are allowed greater distances, not only because they are larger in size, but also because their slope is only required to be 1/8 inch per foot, but you would not have pipe that size for the kitchen drain.

Keep in mind that if you slope a pipe greater than the 1/4 inch per foot, or greater than the 1/8 inch per foot, the allowable distance is going to become considerably shorter the more the pipe is sloped.