Horizontal vent tie in

[Nate E]

Hope I’m not double posting, but couldn’t find my first attempt.

I am modifying the vent tie in for a shower remodel. The previous vent tied in vertically at a tee above the drain, but penetrated the floor within the new shower footprint. I am proposing to tie the vent in to one side of a double tee, with the other side being the shower’s p-trap. The top opening would be capped. The vent would then have a 1 ft vertical section of 2 inch pipe before going up a few feet to tie into the vent stack.

is having a short horizontal section so low kosher? I could not find any diagrams or photos of this configuration.

 

[Tuttles Revenge]

Shower Vent entering Tee from side.

New to plumbing. I had to make a modification to an existing vent for a shower drain. Originally the vent came out the top of a sanitary tee, but this was protruding into the new shower footprint. I’m proposing to have the vent connect to the vertical drain via one side of a double tee. The...

terrylove.com

replies at that post.

 

[Sponsor]

 

[John Gayewski]

Not a good solution. Your drain should probably be in the side wall so your vent can be fully vertical.

 

[Nate E]

Posting Tuttle’s Revenge’s reply here for reference.

“Not sure which code you are in Denver, but most codes have the vent vertical to a point 6" above the flood level rim of the fixture being served before offsetting horizontally. So you need to route your drain to a point to achieve that. In the configuration you have, your waste water can fill your vent.”

 

[Nate E]

repeat post deleted

 

[Nate E]

I agree that it’s not a good solution, so abandoning the straight horizontal section.

I may be able to get enough reach with a long sweep elbow, or a pair of 45s, but in either case, they’d need to connect to the side of the double tee. The drain pipe is offset from the wall by only about 3 inches.

Applicable code is 2021 IPC.

Would it be acceptable to connect an elbow directly to the side of the tee opposite the branch? It doesn’t seem to violate the language of the code as there’s no real horizontal section… though the branch and vent enter at the same level. Wondering what experienced folks would do here.

Thanks,
Nate

 

[wwhitney]

The issue is that the wall above that will receive the vertical vent is offset a few inches from the wall below that has the vertical drain?

Then if you run your shower trap arm along the top (in the picture) edge of the joist bay, you can hit a LT90 to turn towards the drai stack, and then use a 2x1-1/2x2 san-tee. That san-tee can be spun around its horizontal side entry 45 degrees, with street elbows on the top and bottom, to hopefully give you the offset you need. Will require confirming by mocking up a few fittings.

The two 45 elbows could both be on either the drain side or the vent side (with the san-tee barrel plumb) if that works better, but I think having one elbow on top and one below will probably give you a better height within the joist bay for the trap arm.

Cheers, Wayne

 

[Nate E]

That’s pretty slick Wayne. And you are correct, the issue is the two walls are offset. If I’m understanding correctly, I think your suggestion will give me the offset I need.

Just to confirm: working backward, the vertical drain would have a 2 inch street 45, then a san-tee. Above the san-tee would be another 45 elbow then the vent running vertically. The side “inlet” of the San-tee would have a long sweep 90 connected to the shower branch (like the photo shown, minus the extra opening in the tee)

Options: stack the 45s above or below the san-tee to get height needed for the trap arm (1/4 inch per ft slope, length per code)

Thanks,
Nate

 

[wwhitney]

Yes, if the double san-tee (or double fixture fitting) in your photo is replaced with a regular san-tee.

Cheers, Wayne

 

[Tuttles Revenge]

Hopefully that 1.5" 45 is just a prop used as a mock up. Do not reduce the drain from 2 to 1.5"

 

[Nate E]

Finally got around to scheduling the inspection for tomorrow. Below is the assembled system.

Last photo shows the p-trap opening off the mark by about an inch (guess I’m one of those that needs to measure thrice). Im wondering the best way to deal with this. It can be pushed in place with a few pounds of force, but that makes me paranoid. Maybe add a coupling to the arm?

 

[Nate E]

I shimmed it over a little past center and used my wife’s hair dryer to warm things up. Never got hot to the touch and worked like a charm.

 

[Tuttles Revenge]

If its a shower pan you've got to hit that mark as dead on as possible to make your life easier when install time comes.

Looks good otherwise.

 

[Reach4]

Getting shower base in concrete positioned correctly, but could apply to other construction...

 

[Nate E]

Dead nuts baby.