This layout is for a small bathroom in an apartment with a garage underneath. Is this a good plumbing design that meets code (I've attempted to do so)? Or would it be better to tie the tub drain in closer to the 3" vertical stack? Any other suggestions?
Tub, toilet and lav using a wet vent.
- Thread starter Marzec
- Start date
Users who are viewing this thread
Jeff H Young
In the Trades
only need 1 1/2" dry vent
Sponsor
Paid Advertisement
Thanks for your input. Why is a dry vent needed in addition to the wet vent? This diagram is similar to one out of the IPC except in that example there is a horizontal main line rather than a vertical stack.
Jeff H Young
In the Trades
At top of your drawing where you wrote "wet vent " that section is a dry vent and can be 1 1/2 down to the san tee so the san tee would be 2x 1 1/2 x1 1/2
Now I understand what you meant. I thought you were saying I needed to add a dry vent to complete the design. But you're saying the dry vent section only needs to be 1 1/2".
I labeled it "wet vent" since it becomes a wet vent below the lav drain, but where I labeled it it's definitely dry. Thanks for pointing out that distinction. Also, there is an existing 2" galvanized steel dry vent (transitioning to 4" CI through the roof) already in place so I'll just be using a no hub fitting above the lav drain and transitioning to 2" PVC.
John Gayewski
In the Trades
A vertical wet vent needs to be two sizes bigger than the drain served. Since your tub is 1.5" the section that vents the toilet and serves the tub should be 3"pipe. I think this is true in the ipc, I know it's true in the upc.
It's possible I'm wrong and the ipc wet vent sections are governed by fixture units. You'd have to look in the related sections to find out that sections pipe size to be sure.
It's possible I'm wrong and the ipc wet vent sections are governed by fixture units. You'd have to look in the related sections to find out that sections pipe size to be sure.
On https://www.iccsafe.org/wp-content/uploads/20-18927_GR_2021_Plumbing_Venting_Brochure.pdf page 12 is a drawing of a big bathroom group under IPC. It shows 1.5 for the dry part. Of course 2 inch would be good too.
wwhitney
In the Trades
It's just one pipe size larger, not two, for the UPC:
Chapter 9: Vents, Iowa Plumbing Code 2018 | UpCodes
UpCodes offers a consolidated resource of construction and building code grouped by jurisdiction
up.codes
For the IPC, wet vent sizing doesn't differentiate between horizontal and vertical. And just two fixtures on a vertical wet vent is considered "common venting at different levels," rather than vertical wet venting, which is restricted to bathroom groups.
Chapter 9: Vents, 2024 Ohio Plumbing Code | UpCodes
UpCodes offers a consolidated resource of construction and building code grouped by jurisdiction
up.codes
Chapter 9: Vents, 2024 Ohio Plumbing Code | UpCodes
UpCodes offers a consolidated resource of construction and building code grouped by jurisdiction
up.codes
Cheers, Wayne
Jeff H Young
In the Trades
Great its all good ! just use the proper band if its being inspected, here is a little tip, run your pvc above the sink top around 6 inches for your plastic to gal connection because water will never be there and it will never be cause of a leak
John Gayewski
In the Trades
Sorry yes. But this section would still needs to be 3" under upc. As there's more than one fixture draining into the vertical wet vent we would need to be one pipe size larger than the combined dfu minimum. Minimum pipe size for 3 dfu's would be 2". We then go up to 3".
IPC is outta my range slowly learning it.
Similar threads
