Tub Drain Connection in concrete slab

[bmillice]

Hello, newbie here, so I appreciate any advice you pros could give!

I am remodeling a bathroom in my house and will be replacing the tub/tub drain as well. However, I am confused as to what I found when I demo'd the old stuff. I am attaching pictures, but I cannot tell how the old brass assembly is connected to the drain. And, more importantly, how would I attach a new drain assembly to what is coming out of the ground here? My early guess is to cut it off and use a Fernco banded coupler?

(and yes, that is a termite-destroyed sill plate behind the drain. The sills and studs were pretty torn up-it will be replaced before putting the new tub in.)

Thanks in advance!

 

[Standardairconditioner]

First off, good pics! If only new members like you put the effort to post pics. This is exactly why you are getting an answer. I literally ignore new members that try to describe a picture with a thousand words.

You're going to toss that old tee, as that will be replaced by your new tub drain from os&b, whoever. A grinder is your friend here to remove that old tee.

Try to save that short brass that is calked into the flared lead pipe, you may be able to slip your new compression tee onto it.

So I would do that first, and if it's apples and oranges then cut below the flare on the lead pipe, and Fernco to that.

 

[Sponsor]

 

[c_g_lima]

If you don't mind my intrusion in this discussion, I understand this is a lot more work, but would it be better to completely remove that galvanized drain pipe all the way to the trap and use one of those service weight gaskets/donuts to connect a PVC/ABS drain pipe? I am assuming the trap is cast iron.

I am dealing with a similar situation at my house, and in my case that drain pipe you are suggesting the OP to keep has a lot of corrosion. I don't see much corrosion in the included pictures, but I believe at some point it will start to form. The pipes at my house are almost 60 years old.

 

[bmillice]

Thank you all for your attention to this! I really appreciate the advice!

@c_g_lima, the problem with replacing the entire drain pipe all the way to the trap is that I can't seem to access the trap. I tried digging down further, the foundation concrete pretty much closes off at the bottom, I don't seem to have access further down without busting up concrete at the bottom.

I was able to easily remove the old brass assembly and save the stub of the brass pipe.

So, my next question is, the new pvc drain assembly I have is 1-1/2" PVC, this brass pipe is 1-1/2", so what is the easiest way to join them together? Use a PVC slip joint or a Fernco?

Thanks again!

 

[Standardairconditioner]

Good job on the followup! So many new members just post once and they disappear.

Get some 320 grit wet sandpaper (yes, use water) and try to clean the outside of that brass up.

You just might be lucky to get your new tub drain to slip onto it. Got nothing to lose to try this first.

Problem with the Fernco is that it might extrude things too high.

 

[bmillice]

OK, so that's kinda where I'm confused. The new tub drain assembly I have is EXACTLY the same size as the brass pipe:

So, there is no getting the PVC inside that brass pipe. Given that, can I just use a simple PVC slip coupler? Or would I need to use something else? There is a ton of room to trim the bottom of the PVC drain assembly, so finished height won't be a problem.

 

[Standardairconditioner]

Fernco it is!

 

[bmillice]

Awesome! Easy enough. Thanks again for all your help!

 

[Standardairconditioner]

Since you aren't changing the trap, might want to take the opportunity to snake the hell out of it now.

Run a garden hose into it as you hand snake it.

I'm sure it gave you no probs before, but it'll just loosen up whatever little was clinging to it.

 

[bmillice]

OK, so after some more research and the advice posted above, I decided to do all this the right way while I've got the tub ripped out as I don't plan on doing this again anytime soon. So, I used an angle grinder with diamond blade, cold chisel and hammer to bust out concrete until I found the cast iron hub, got the lead pipe out and cleaned out the hub. Used a Fernco donut and got the 1-1/2" PVC in there (with hammer and dish soap), to a depth of over 3".

Two questions:

1) Is the 3.5" of depth into that pipe enough? The Fernco donut itself was less than 3", so I figure that's all I needed.

2) What do I need to do to fill in/repair the concrete I chiseled out? I'm through to the dirt underneath, so do I just fill in with a thin layer of concrete under the pipes but over the dirt to seal out bugs or do I get the trap on there and then cement the entire thing, encasing the PVC in cement?

(and yes, I removed that blue rag from the CI hub!)

Thanks again in advance!

 

[Terry]

Three inches is plenty there.

It looks good there. If it were Washington State, we would just leave the hole in the concrete. If you do seal it, I would wait until you have the tub waste and overflow installed.