DIY Basement Utility Tub

[Tim C]

I'm looking to install a utility tub in my basement. I'm reasonably competent but this would be the most ambitious drain/vent project I've taken on. If I get any terminology/parts wrong please correct me! And sorry if the images don't post correctly, I tried inserting them as thumbnails.

Seems like this should be a pretty straightforward job, just want to make sure I'm not missing anything. Here is a rough drawing of the overall layout. Red lines are all new, dark blue lines are an existing 3" stack that serves a powder room (sink, toilet) on the first floor:



Here is a close-up of the actual stack:



So my thought here is to cut out the cleanout and put in a 3x3x3x2 tee, like this. The stack is about 16' from the sink, so I need to make sure I get a 1/4" per foot drop on this pipe. Making the corner will be kind of tricky so I will probably end up doing two 45's instead of a 90 degree elbow on the drain. Am I on the right path here?

The vent will attach to the drain line roughly where shown, I assume with just a regular tee. The vent will tie into the vent for the powder room I mentioned on the first floor. It's finished but a little drywall work isn't an issue. This photo was taken during construction:



So again I assume just a standard tee to tie into this, at least 42" above the floor. Here's my second question - when I drill up through the bottom plate, do I need to worry about protecting the pipe with a nail plate? I'd rather not touch the drywall/trim if I don't have to. Come to think of it, it doesn't look like the builder did anything... 2" pipe through a 2x6, no nail plate required?

Thanks in advance for your help and any additional advice!

 

[WorthFlorida]

Nail plates are cheap and are good assurance from punchers. Do use them where cabinets will be installed. A 3” screw can get pretty deep into the stud. Be sure that the tee for the venting are in the correct position, that is should water get into the vent pipe that it can easily flow to the main stack.

https://www.co.lincoln.or.us/sites/..._-_helpful_hints_residential_construction.pdf

 

[Sponsor]

 

[Tim C]

Thanks for the reply. That PDF is very helpful! I see similar examples of how I plan to connect into the stack with the sanitary tee.

Understood on the nail plates - thing is, that space on the first floor is already finished, so I don't have easy access to install them. I'm not trying to save money on nail plates, I'm thinking about the time involved in re-finishing that space.

Does one normally worry about nail plates if remodeling in a finished space?

I was thinking about making/finding a thin walled pipe (not like HVAC, I'm thinking metal conduit) that I could run up through the floor first, sort of like a protective bushing. Secure that in place somehow, then the vent pipe would stick up through that.

 

[WorthFlorida]

If the walls are already finished, nail plates are not needed. It passed inspection.