My neighbor wants to remove a bathtub and move a washer and dryer into the same space. The tub drain is 1-1/2" Sch40 PVC: a P-trap into a 1-1/2" coupling on an 1-1/2" stub into a 2x1-1/2" bushing in the back of 2" wye, all below the floor. Is there a way to replace the 1-1/2" P-trap with 2" by hooking onto the 1-1/2" stub (just a short constriction)? If so, should the new trap be above the floor to limit the height of the standpipe above it? Montana code calls for 2" drains on clothes washers.

Can you cut the bushing flush with the back of the wye and use a ram bit to remove the remainder of the bushing ? That would give you 2" all the way. If you put the trap above the floor it will have to have another vent.

Thanks for the response. I guess we would need to cut the 1-1/2"pipe flush with the bushing and use a 1-1/2" ram bit to clear out the rest of the pipe before we could use a 2" ram bit to clear out the bushing?



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Since I had to open up a 2" hub by drilling out a 2x1-1/2" flush bushing with a 1-1/2" pipe stub inside, I turned a 1-1/2+" wood pilot on my lathe, bored 1/4", and put it on a 1/4" rod in a 2-3/8" hole saw mandrel. With this rig I was able to cut out the bushing using the stub as a guide for the wood pilot. I was able to chuck the hole saw in a 3/8" 18v drill and use the clutch to control jams. I was able to rock and finesse the hole saw until the bushing base broke loose from the hub. With plenty of solvent and cement, the 2" pipe will work fine in the hub.

Thanks for setting me on the right path!

Jerry, I've often installed a smaller holesaw inside a larger one to act as a pilot. Good job with your lathe solution.