Installing a direct drain for tub

[Suceress]

I may have mentioned in another thread that I discovered the previous owners screwed up when renovating my bathroom by cutting through a joist for the tub's drain. I thought it was just notched, but last time I crawled under there (sans camera) I discovered it is cut all the way through. I can only see the P-trap coming down from the overflow so it must be an above-the-floor drain & the tub shoe is not visible.

I want to correct the issue by removing the existing P-trap and modifying the setup to have a direct drain. So, instead of having the P-trap below the overflow, it will be below the tub's drain & the overflow will go to the tub drain. I'll have to cut a hole in the floor to access the tub's drain (it's 1st floor on house on blocks-- below is just dirt). I want to put a block inside the cutout in the joist to fill the void & sister it up with another joist.

I want to make sure I get all of the right parts and configure it correctly.

So, instead of a tub shoe I'm thinking of getting a Westbrass 1-1/2" straight adapter (https://www.amazon.com/Westbrass-442P-ABS-Adapter-White/dp/B01MU7ECKA/)

Getting some sort of tub to drain gasket/washer to go under the tub but above the adapter, I'll need an appropriate drain to thread in from the top (thinking of using pipe dope on the female end and teflon tape on the male end). For the overflow I need to find just the piece that connects to the back of the tub's overflow, a gasket for it, the overflow cover (thinking a Watco innovator type that has no visible screws), and I'm debating whether I need a long sweep or a shorter elbow (I'm leaning toward long sweep). I'll bring them together with a sanitary tee (sweep going down). Underneath that I will have a 2"x1-1/2"x1-1/2" sanitary tee hub to make my P-trap 2" for better drainage. It will only have to run a few feet before I can run a vent up inside the adjacent wall and merge it with an existing vent by branching over.

Any recommendations on tub drain gaskets? Or overflow gaskets? I'm having a hard time just finding the overflow part without the rest of the assembly.

I saw a kit somewhere that could be put together in different ways so it could have the regular overflow setup or direct drain but I didn't like that it wasn't a sanitary tee for one of the pieces. I'll have to find it again, but it's 2am & I just got nagged to go make dinner.

I'll try to add sketches/pictures later.

 

[Terry]

They make tub drains that go vertical.
Watco direct drain.

 

[Sponsor]

 

[Suceress]

Thanks! I need to price that one out as I've seen it before. I will have to do the measurements to make sure it would reach. I had some concerns about mice or critters chewing through the green piping. I may just put some peppermint oil on it at installation though-- mice hate that stuff.

I saw this one: https://www.amazon.com/Keeney-71W-Style-Triad-Chrome/dp/B000H5Q09I but wasn't sure if the design would cause clogs.

I also saw this one https://www.plumbingsupply.com/direct-bathtub-drains.html that comes in different parts that can be purchased separately so I can use a different overflow cover and stopper.

My tubs right now have rubber stoppers that gets put in when we want to plug the tub so we can put a hair-catcher in the drain. I suppose if the little stopper can be removed when not in use it will be fine.

The only Watco green one I could find was $75 and I'm not sure it's long enough, but I did find this one https://www.plumbersstock.com/watco...drain-polypropylenepvc-pvc-chrome-plated.html
I'd leave the plug part out because I would not want that thing underfoot. I think I want to do this direct drain thing with both tubs (when I get around to putting in another tub).

(I hope the links are OK-- I've never shopped from any of the sites so I don't know how good they are- just showing the products).

I really appreciate the info and pics. I've been googling but had a hard time finding stuff but after you mentioned things the last Watco one popped up.

 

[Suceress]

Update: I purchased a Jones Stephens direct drain. Installed one on my friend's tub. The stopper on it broke so he put a regular plug in it. I'm planning to get a strainer and some sort of flat plug for mine. I will install the direct drain on two of my tubs (floor joists permitting). I know my tub can use a direct drain.

 

[Tuttles Revenge]

I prefer the glue together style because they just can't come apart after they're glued together and because they use 1.5" pvc dwv fittings and pipe, you can offset and change direction easier if you need to.

But I've always liked this style of tub drain since the first time I installed one to solve a framing issue. I was told that they're more common on the east coast.

 

[Suceress]

The Jones Stephens one I got is solvent weld I believe. It's a half kit so it has the overflow part and a sanitary tee designed to fit under the tub. The tee has a drain & stopper at the top. Framing is an issue so I may need extensions. That's a good point. The pipes will be perpendicular to the joists. I will have locate the joists and hope that there isn't one in the way. Worst case I could drill a small hole through so long as I don't go too high or too low and get it right in the middle. I don't think the tub we got has an above floor drain. If I'm lucky, there won't be a joist in the way. That's something I'll have to determine by crawling under there and seeing where the water supply lines are relative to the joists and measuring. Ok, I'll have my skinny friend climb under since my fat behind won't fit.

Something like this kit: https://www.homedepot.com/p/JONES-S...te-Half-Kit-in-Chrome-Plated-B07103/314249743

 

[Tuttles Revenge]

Theres always a joist in the way. Thats the 5th rule of plumbing tubs

 

[Suceress]

The idiots who installed a tub in my bathroom didn't check the joists and the P-trap was directly over a joist. They didn't just notch it either. They cut all the way through so it is no longer connected. I'm going to have to make a box to reinforce it on either side of the cut and I want to sister up that joist over that hole just in case. Then I'll do the direct drain so the P-trap won't be over a joist. Said idiots also installed carpet in the bathroom.

 

[John Gayewski]

If I were you I'd put a 2" santee and Bush down. That way if it ever needs to be changed to a shower drain it can be drilled out and replaced with 2". Rather than having to repipe everything.

 

[Suceress]

I thought about using a 2" P-trap after a bushing to increase the pipe size. I am not concerned about future upgrades. Not planning on converting it to a shower anytime in the next decade. If it ever gets changed it will likely be after I've moved or died. But, it's something I'll keep in mind.