Hello,

I'm doing my first bit of plumbing and have a decent sized project ahead of me. Before I get to far into things I wanted to reach out to get some feedback on my proposed plan. Please let me know if you see any issues with my plan or have any feedback. You should be able to view the sketch I made here: [drive.google.com]

This is a two story house with each floor containing the same set of fixtures. Each has a bathroom with a toilet, tub/shower combo, sink and a kitchen with a sink and a washing machine.

Let me know if you have any questions or anything is unclear.

Thanks!

Neither tub is vented. You'll need to add a vent to both. Here in NC the washing machine can't share a branch with another fixture, it has to enter the stack separately , it might be code compliant in your area.

My impression is that, for both bathrooms, the lav vent(2" serve as the 'wet vent' for both the toilet and the tub. Is this not the case?

EDIT: Looking closer, I see how the first floor tub would have an issue - the toilet flushing could siphon off the tub trap. However, is the second floor setup (sink with vent tied in between the toilet and tub) acceptable? If so, I can change the first floor setup to be the same order.

Thanks for the tip around the washing machine - I'll research to see if it can share a line with the sink.



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[www.google.com] Don t forget your full size clean out At the base of the stack.



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I've updated the plan which can be viewed here: [drive.google.com]

I changed the bathrooms so that the tub drain joins with the lav drain/vent before joining with the toilet. I also added a clean out at the bottom of the main stack.

Is this suitable?

You might have a problem with wet venting the laundry standpipes. The kitchen sink requires a 2" drain and the wet vented section needs to be one pipe size larger than required by the upper fixture(kitchen sink). I don't see anything stating you can't wet vent the laundry, but you would need to increase the drain piping up to the tee(including the tee) for the kitchen sink.

your second drawing is closer. you need to have the lav "Y" off of the tub drain. not have the tub "Y" off the lav drain.
run the drain straight to the tub. put a 2 inch "Y" in that drain with the side of the "Y" rolled up and picking up the lav.

Would it be 2 1/2" or 3"?

Thanks for all this feedback - much appreciated!

Here is my third version of plans: [drive.google.com]

I added in a separate vent for the washing machine that quickly joins back with the sink vent (I'll make this at least 6" above where there could be water there).

I also changed the bathroom layouts so that the tub drain goes right into the toilet drain, and then the lav sink drain drops into the tub drain.

I'm planning on using 3" pipe for the main stack and for the toilet lines and then 2" everywhere else. It looks like I could get away with 1.5" in some places, but my thinking is that 2" would be less likely to clog.

It's looking good, you just need to be careful that you don't create a partial S-trap with your tub traps. As long as the drain from the trap stays near horizontal from the trap to the 3" pipe you'll be ok, The lavatory drain can drop down into that run. Not vice versa.

looking really good.

I think that I understand the note about the risk for creating an S trap, but I wanted to clarify so I drew a couple of example diagrams: [drive.google.com]

I believe the correct approach is the one on the left where the tub trap is lowered vertically as necessary so that(with a slight slope to allow for draining) the tub line goes horizontally from the trap into the WC line with a wye placed horizontally/flat.

I think if I put the tub trap too high and then have to drop the line vertically after the trap(either right away or when it goes into the WC line) then there would be a partial S trap created. This is what I tried to show with the right diagram.

Sound accurate?

That's correct.

your drawing skills leave a little to be desired but your grasp of plumbing concepts is growing by leaps and bounds... good job...

haha...I'll have to work on my drawing skills.

Right now, I'm just happy to be learning more about how to design things correctly - thanks again everyone!



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