You need to either open up the wall in that bathroom or on the other side and rough the sanitary line in at the proper height. Don't fuck around and try to reinvent the wheel when it comes to plumbing, it never works. This shit was figured out long before we got on earth by far more intelligent people than we will ever be
this post was submitted on 15 Jun 2025
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You need to focus on both of these two things:
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Regardless of the bends, is the pipe's height at output significantly lower than its height at input? If yes, you're good
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Does the bendy part go up and down enough such that it could trap enough water to fully block the pipe? If yes, you're good
So...yes? I know there's enough room for about a 2% slope.
It sounds like you're probably good.
The slope itself shouldn't matter as long as the drain hole at the bottom of the sink is still higher than the drain hole in the wall. You can also angle the p-trap itself a little bit, but it still needs to be able to hold enough water in the bottom to block the pipe.
Oh I see. Yes, the sink is set about 20 inches above the wall hookup.
No photos?
There's about 3 inches between the outlet and the bottom of these 24"x24" square cabinets.
More like 4" on the left side, but the right one is a bit lower.
Is that fresh rough in pipe? Fire the plumber or have them come back and open the walls to move those up. Or move the cabinets down tops seem custom? No ID why they are set that high above other bases? Nor why they shouldnt be moved down. You storing ferret beds under there or something?
The tops are not in. I wouldn't go further without fixing correctly. No amount if pitch on a trap arm is gonna fix that
Nah, it's just a design choice, it's for my parents and they didnt want a big solid rectangle. Anyways the counter tops are in now, so that's not changing. Personally, I would have kept the tops all level, but it does look nice and architectural all finished.
And we do all know better, and he confirmed placement with us, so it's our fault, really, just a very stupid oversight.
Then try to offset them in the cabinet with street vent elbows and spin the trap sideways to leave room for the arms reduce to 1-1/4" trap to save some space
Thanks for the advice! It won't be necessary anyway, with the traps going in, but I will save this and suggest it if it gets changed to normal p trap later.
Photos would definitely help.
This is clever as hell. Don’t know if it’ll pass code though if you’re already permitted. I’m sure it’ll work just fine, but how long is unknown since it’s new(er) technology.
If you have enough space, it looks like this one might be a better alternative since you can open the front to clean the membrane out (which you will need to do to keep it sealed over time).
This is for non daily use in an RV set up. This will fail and your sinks will be constantly slow/ smell like shit.
Well, we'll see, it sounds like normal trap won't be a problem. They are supposedly pretty not uncommon in the UK, for space reasons, and people seem to like them. It's daily, but light use, and unoccupied in the summer. So unless it fails from pure friction and wear, I don't see how it could really be an issue, but yeah, things do have a tendency to be made like cheap lowest bidder garbage, so....
I am not into plumbing, but this is so cool. I'm spreading the word.
Yeah, it's really clever, and elegant, and takes up no space. Maybe I'll do an update post later to report on performance.
It seems like it shouldn't be difficult to get city clearance, it's more about if we don't like them.
We dont like them
Well, the house is unoccupied during the very hot Arizona summers, and these never lose their seal when clean. And also, it's the master bathroom in a detached guest house, so it's mainly just used in the morning and night, with basically nothing more than soap and toothpaste. No little kids pouring paint and whatnot down the drains.
Also, the house has no basement and very little storage, so the more space, the better.
Would not recommend that RV trap. Will get very funked up on hand sink with toothpaste and hand soap. Slope doesn't matter much on such a small run. If your pushing the arm up you are adding more pitch which won't hurt especially if solids are not running down it.
Can't really understand where your clearance issue is. But it sounds like the outlet at the wall is to close to the base of the cabinet? If so u can try to modify the cabinet base/ cut a hole for the bottom shelf to make room for the trap. If the outlet is too high for the base of the sink you could try a low inlet trap. Otherwise if you have room for extra fittings you can 90/ elbow up right at the wall and then 90 back out for your trap.
Or just jam that shit up at an angle. The problem will come when that cocks the trap at an angle that you cant get a tight connection onto the tailpiece coming down of the popup on the sink. Don't recommend slinky pipes but its not my house so do what you want.
The wall hookups is too close to the cabinet bottom, and there's not enough room for the U. I'd prefer not to cut a hole in it if possible.
@RampantParanoia2365@lemmy.world based on the image, I think a bottle trap would work and be to code most places.
https://tapron.co.uk/blogs/news/bottle-trap-vs-p-trap-choosing-right-plumbing-component
Really? It seemed to be against code in most places near me, along with S traps. I don't live in the UK.
Probably the pipes get ugly if the plumber is trying to install 11s and 22s. Probably they will have a different idea.