Adding a washer to a garage.
Installing plumbing in the garage is sometimes done after the home had been completed. In this instance, a 1959 home with a combination of cast iron and galvanized.
The previous homeowner had run thin wall PVC from the kitchen sink through the cabinets to the garage, and added some fishnet looking tubing that direction. All of this into the kitchen sinks 1.5" drain.
Looking in the crawlspace I was able to find a 2" cast hub which allows for bumping pipe size to 2". For the water supply, new 1/2" PEX lines, insulated in the crawl space.
The "Before" picture
The old drain connecting under the sink. The shutoffs were removed and replaced with new 1/4 turns, and a hot stop added for the new dishwasher to be added later.
This is the kitchen line that was also taking the washer's water too.
The previous 1.5" pipe was pulled from the hub, and the lead pried out.
The hub is now ready for a Fernco hub insert and 2" ABS pipe.
Adding about 12 feet of 2" in the crawl space, At the far end it connects with the new 2" pipe coming out of the 4x2 combo.
The "After" picture
A new standpipe in the garage with hammer arrestors on the washer supply.
The washer got a 2" cleanout for the end of the run.
And no, I did not do any of the electrical here.
A neat job, and what follows is not meant to be critical, but rather to illustrate how codes can vary by region, if not by municipality. My plumbing background is in the Los Angeles area. I've been away a few years, but I think what I am going to say still holds. First of all, the wall between the garage and house is required to be fire rated and cannot be penetrated by plastic. That means the WM box has to be metal and the clean-out cast iron (or copper) with a brass plug. That mechanical vent, that goes - VTR only. Also the PEX is out, it would have to be copper or galvanized. Both ways will operate fine, but that installation in the burbs of LA gets turned down on multiple counts. I just find that interesting.