I received your photo via email and it appears that the water supply is simple.

on the cold water side you can cut the existing faucet off the cold water drop, install a 90deg El and pass through the stud, then install another 90el and turn up to a thread adapter to connect to the valve.

ON the hot water side there should be no problem keeping the line in the same stud cavity. I would suggest you begin by loosely attaching a thread adapter to the hot water faucet on the washer box, then fit a short length of copper to drop down 4" to 5" (do not solder at this time). Attach a 90el on the bottom of the drop turn towards the stud on the left. Now hold a 90 against the stud and measure the length between the two 90's and cut a short nipple to connect the two 90's. Next cut a length of copper to make a riser up the stud to any convenient point where you can 90 across and connect to the hot water drop. At this point you can disconnect the thread adapter from the faucet then you will be able to take the thread adapter, the drop, cross nipple and the riser to a bench to clean and solder it. In this manner you have no risk of damaging the washer box or the insulation from heat during the soldering process. Once you have that section soldered together you will have a J section that can be inserted behind the washer box bracket and up to the crossover at the top. You can then solder in the cross tube on top and install a pipe hanger at both the top and bottom of the riser on the left.

Having resolved the water supply I then turned to the drain system, however when I first looked at the photo something caught my eye but I couldn't put my finger on it. The more I looked the more problems I noted, but to be sure I went to the code book to double check. Normally I could lay out the DWV for an entire house without looking in the code book but for as simple as this looks, I had to burn the midnight oil to find all the problems.

The washer box, standpipe and P-trap are fine but it is difficult to scale the length of the horizontal line from the P-trap to the double Tee. Code requires that the horizontal distance from the trap weir to the vent opening must be 4times the trap diameter. The trap is 2" so the horizontal distance from the trap weir to the vertical riser must be 8". Assuming the studs to be 16" on center it would appear that the horizontal section is too short.

The next thing that caught my eye was the use of the double tee with a riser to the sink. The standpipe is receiving a powered discharge and the sink would be a gravity flow. We are not supposed to connect a powered flow and a gravity drain on a double tee. I am wondering why they used a double tee with a riser to the sink when it would have been much simpler to install a sanitary tee for the standpipe, then move up the the sink waste arm level and install another sanitary tee for the sink waste arm?

Obviously this riser is connected on the end of a horizontal line under the floor. Code requires a cleanout on the upstream end of all lines, therefore there should be a cleanout on the riser just above the double tee.

The riser is receiving the discharge from the standpipe, a laundry sink and the kitchen sink above, therefore under the IRC the section of line from the standpipe connection to the kitchen sink above is classified as a "Waste stack" however this riser has an offset just above the double tee and the code prohibits any offsets on a waste stack.

although not visible in the photo, the post states that the riser terminates at the kitchen sink above. If that is the case there is no vent on this line. There should be a tee for the kitchen sink waste arm and the riser should continue up to the roof for a vent.

At the base of the riser it appears that they have glued ABS to PVC under the floor. Code expressly prohibits gluing dissimilar plastics together. (The IRC will permit a maximum of one dissimilar joint per structure with the expressed written consent of the local inspecting authority.)

Although it is very difficult to tell from the photo it appears that the 2" ABS might be connected to a 1-1/2" PVC from the floor. If so, this again is a violation because code prohibits downsizing a line in the direction of flow.

Now let us consider the DFU load. The standpipe is rated at 2DFU, a laundry sink is 2DFU's and the Kitchen sink above is 2DFU's therefore the combined load is 6DFU's. Under the IRC a 2" horizontal line is rated at 6DFU's and a vertical 2" line is rated at 10DFU's so at first inspection it would appear we are ok here, but a 2" "Waste stack" is limited to 4DFU's. In order to combine the standpipe, a laundry sink and the kitchen sink above on a common waste stack, it must be a 3" stack.

Lazypup,

Thanks for your response. I did route the hot and cold to the laundry box as you suggested, and everything is working fine.

Regarding the drains, I didn't install this setup, this was done by a state-licensed plumber when the house was built 4 years ago, and supposedly inspected during that time. Given that fact, I guess I'm trying to figure out if there are operational issues that I might encounter in the future, and exactly what I should do about the violations, if anything. If I am unlikely to experience any significant problem related to this configuration, then I suppose I could let it be given the fact that it already, somehow, passed inspection when the house was built. If there's something here that is just not a good thing, and I need to correct it, I need to figure out how to make that happen without opening a can of worms.

The waste arm from the washer P-trap weir to the double T is probably not 8", it might be 6", but it sounds like this is the least of the code violations here. Should this really be 4x the diameter or just 2x?

I noticed the apparent PVC-to-ABS at the base of the riser also, though I do believe that it's 2" PVC. I can't tell for sure (was there ever white ABS?) but I'm guessing someone needed a piece in a hurry and stuck in PVC. It appears that the PVC is 2", however, so no downsizing here. Whether or not an exception was authorized is unknown to me.

You noted the offset, but if you follow the riser up into the ceiling, there is also a short horizontal section before the riser continues vertically up to the area behind the kitchen sink. I assume that this horizontal section is okay, and that the offset problem could have been eliminated had this horizontal section simply continued so that the stack lined up with the double T at the base.

Regarding the vent and the kitchen sink: there are two of what appear to be AAV vents under the kitchen sink. It appears that the sink, disposal, and dishwasher all drain into the same waste line.

Thanks,
JKG