plumbing a kitchen sink

[russell]

I am in the process of of plumbing a new kitchen sink. I hesitate to go by the dimensions and locations of the old sink piping as all the plumbing in this house was done poorly. I am looking for the distance off the finished floor for the waist arm and the water supply angle stops. Additionally what is the rule for plumbing the vent from the waist arm. Any illustrations would be helpful. Is there a master plumber out there that can help me.

[LazyPup]

There is no hard and fast rule in the plumbing codes that would dictate the placement of the waste arm however, the Plumbing Codes do limit the length of a drain tailpiece to a maximum of 24” vertical when measured from the drain opening to the water level of the fixture trap.

The codes require that we must have a shutoff valve on all fixture supply lines with the exception of a shower mixer, but here again, there is no hard and fast rule as to where the valve must be located. By convention the “Angle stop” valves are used as the point of transition from the “Pipe” in the wall to the “Tubing” used to make the fixture supply lines. Understanding the preformed supply tubes are made in 12”, 16”, 20” and 24” lengths, it would then stand that the angle stop valves would by necessity be within 24” of the faucet assembly.

I have attached an illustration of the common setup dimensions but you should be very careful here. The dimensions in the illustration will work fine for a typical kitchen sink, or even a standard sink with a garbage disposal but before installing the waste arm we must check the final trim out specifications closely to insure they are not calling for a specialty type sink such as a deep under-mount sink with a disposal unit which might require placing the waste arm lower.

The length of the waste arm depends upon which code you are under.

Under the International Residential code a kitchen sink is required to have an 1-1/2" diameter waste arm and it may be a maximum of 6' total developed length when measured from the trap weir to the vent opening.

Under the Uniform Plumbing code the kitchen sink trap is an 1-1/2" but the waste arm Must be 2" diameter. Under the UPC a 2" waste arm may have a maximum developed length of 5'.