Ceramic Tile Advice Forums - John Bridge Ceramic Tile

Ceramic Tile Advice Forums - John Bridge Ceramic Tile (https://www.johnbridge.com/vbulletin/index.php)
-   Tile Forum/Advice Board (https://www.johnbridge.com/vbulletin/forumdisplay.php?f=1)
-   -   ABS Shower Drain on Cast Iron Drain Pipe (https://www.johnbridge.com/vbulletin/showthread.php?t=130368)

nickhay13 01-10-2021 03:44 PM

ABS Shower Drain on Cast Iron Drain Pipe
1 Attachment(s)
Hi All,

I've been referencing these forums for years for DIY projects in my home and you guys got me through my last bathroom remodel with ease. I've finally had to make an account because I have run into an issue which I'm not 100% clear on.

I'm in the process of remodeling a bathroom and I've completed the tear out. The old shower was a mud bed with a hot mop and I'm down to the concrete sub floor. Today I started the process of removing the old shower drain to install a new three piece drain and discovered that whoever last remodeled this shower glued a three piece ABS shower drain assembly directly onto the cast iron drain pipe. This seems to have held up fine for many years (I've owned the home for 8 years and this was done long before that). However, to my knowledge that is a no-go.

I just want to make sure I'm not missing anything or an easier way to accomplish this because going forward I'm under the impression that I need to cut the concrete and dig down beyond the P-Trap and use a mechanical coupler to tie a new ABS drain pipe into the old cast iron (with a new ABS P-Trap and drain pipe coming up vertically that I will glue to three piece drain into.

I have attached a picture for reference. Please ignore the holes in the drain assembly, my inside pipe cutter was not big enough to cut the collar off of the drain so I was in the process of drilling the old drain assembly out until I realized I was dealing with cast iron below.

Any insight is greatly appreciated.

Davy 01-10-2021 04:56 PM

Hi Nick, welcome back. I'd go ahead and bust more concrete out along with some dirt, then post another picture. Is the drain already centered or do you need to move it?

nickhay13 01-10-2021 05:50 PM

Hi Davy,

I have not cemented anything as I haven't installed the new drain yet. I do not need to move the drain, I just believe I need to get rid of the cast iron P-Trap and vertical pipe and replace with ABS in order to glue in the ABS drain. I won't be able to cut the concrete and dig more up until next weekend.

Edit: I misread centered as cemented.. my apologies. But no, I do not need to move the drain.

jadnashua 01-10-2021 06:16 PM

There's one possibility that may work for you without tearing things out completely.

Is the end of that cast iron a hub?

Fernco, and probably some others, make rubber donuts that are designed to sit in a hub, and allow a pipe to seal inside it. https://www.fernco.com/plumbing/donuts-o-rings/donuts

nickhay13 01-10-2021 07:14 PM

Hi Jim,

Unfortunately it is not a hub, it's just a cast iron pipe that the current drain is glued to. It sounds like I will be digging up the whole area and replacing the entire setup with ABS from before the trap.

jadnashua 01-10-2021 09:36 PM

Another alternative would be to cut the CI pipe off some, then use a no-hub connector to attach a short ABS riser to it, and then glue your new drain onto it. Whether that's an option would depend on how tall the existing riser is. Or, if there's a hub below, use the donut, an abs riser, and glue on your new drain. The donut gives you a little leeway about getting the drain perfectly level if the current riser is not perfectly plumb. To remove a pipe from a hub, you normally would drill out the lead making it sort of like Swiss cheese, then you should be able to rock the pipe back and forth, and pull it out. Clean up the hub with a wire brush, insert the donut and go.

But, since you may not know the condition of the p-trap underneath, it can make some sense to tear it out and replace while you're replacing the shower. CI can last eons, but under some situations, it could be corroded nearly through.

nickhay13 01-16-2021 07:27 PM

5 Attachment(s)
Hi All,

I appreciate all of your responses. I ended up cutting up the foundation today and digging it all out. It turns out that my drain line is ABS, but for some reason whoever did the plumbing put a cast iron P-Trap onto the ABS drain, and then an ABS shower drain on the cast iron P-Trap.. Not sure what was going on there. Anyway, I tore it all out to the ABS drain line and replaced it all with ABS. I have not cut the vertical drain pipe yet as I need to figure out exactly what height my drain needs to sit. A portion of the foundation floor is already sloped towards the drain but the rest of it isn't so I think I'm going to fill in the hole, concrete it up, and then pour self leveling concrete on top once I build my curb so I have a nice level surface for my pre-pitch.

Anyway I have attached a few pictures of todays work, including the removed parts.

Thanks again for the insight everyone.

cx 01-16-2021 09:04 PM

Nick, there is no reason at all to go to any length to level that floor to accommodate a mortar pre-slope. Just make your patch, install your clamping drain, and make your pre-slope.

My opinion; worth price charged.

nickhay13 01-16-2021 10:20 PM

Hi CX,

I'm not a professional so my reasoning to level the floor prior to the pre-slope was to have a level surface for part 1 of the three piece drain so I don't have to fuss with different heights around the drain for the slope. I could be missing something, but it seems like the most simple approach for someone of my skillset. If there is a better or easier way to handle it I'm all ears.

jadnashua 01-16-2021 11:01 PM

Assuming you're using dry pack to build your shower pan, that part will become the proper height and slope, regardless of what's underneath as long as you've made a structurally sufficient patch to the slab.

You make a level line around the perimeter to set the outside height of the pan sufficient for the required slope to the drain, then fill it in...The dry pack could care less about what's underneath it.

Now, if you're planning a preformed pan, then yes, you'd want to level things first, at least somewhat, depending on the pan you're planning. Some can be set in deck mud, and then, you don't care. A solid one, though does want it level first.

CaliGrown 01-17-2021 05:46 AM

Nick, I would check out YouTube for some mud work tips. I used to get caught up with over prepping for prep. Sal DiBlasi, Tile Coach (Isaac Ostrom), Dave Blake, Donnie D, Stud Pack, Craig Harimon, and Hamilton Tile GA (Ben Santons & Jason) are all good & different sources on YouTube for tile & mud tips/tricks/gen. info. JBF is best place for your Q & A, and progress as everyone is here for your successful proper Shower/Tile build.

Davy 01-17-2021 09:46 AM

Nick, the bottom flange on the 3 pc drain needs to be about 3/4 inch higher than the concrete slab height. Use a short straight edge of some sort (2 ft level works good) to bridge across to figure out where the riser pipe needs to be cut. Once your drain is glued in, you can then fill in the hole. If you fill in the hole before installing the drain, hold the fill down low enough to glue on the drain.

All times are GMT -6. The time now is 10:36 PM.

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Copyright 2018 John Bridge & Associates, LLC