Shower stall drain under slab

[Claraarcher]

Hi,

As everyone in this forum was very helpful in helping with some rough in and venting and am once again asking for some help.

I am getting to the point of build out the shower stall on first floor and the old drain looks to be copper / brass into a cast iron trap. I need to move this towards the left wall to accomodate a new shower base. i cant tell if the pipres are leaded in to the hub or using a rubber transition but i can wiggle it a tiny bit side to side so i think it may be a rubber transition.

My questions are: 1) what is the easy-er way to relocate? cut out old trap and connect new pvc? pull out the copper pipes and use a donut to attach pvc?

2) if i cut the old trap out will the coupling last under ground or do i need to cover the metal clamps to they dont rust out?

3) would PVC be eaiser to use when having the mud base put in?

pictures attached and i hope are helpful

Th

anks!!

 

[WorthFlorida]

You would want the trap directly below the shower drain. You have a 1.5" drain. The maximum distance from the drain to the trap is 15". If you use this trap in its location, where will it be on the floor plan? Also, can the 1/4" slope be achieved? If it ever collapsed you'll be chopping the tile and floor to get to it. I would go back as far as you can and use ABS or PVC and transition to the CI.

There are different opinions if a 1.5” inch drain or 2” drain pipe is required. Since all shower drains are 2”, the drain pipe will have to be 2” all the way to the main stack. Hence cutting the CI section out for a 2” connection.

Cast Iron has a lifespan of 75-100 years but you don't know that the inside of this pipe might be like. Like an old car, it could be rusting away from the inside out.

 

[Sponsor]

 

[Claraarcher]

You would want the trap directly below the shower drain. You have a 1.5" drain. The maximum distance from the drain to the trap is 15". If you use this trap in its location, where will it be on the floor plan? Also, can the 1/4" slope be achieved? If it ever collapsed you'll be chopping the tile and floor to get to it. I would go back as far as you can and use ABS or PVC and transition to the CI.

There are different opinions if a 1.5” inch drain or 2” drain pipe is required. Since all shower drains are 2”, the drain pipe will have to be 2” all the way to the main stack. Hence cutting the CI section out for a 2” connection.

Cast Iron has a lifespan of 75-100 years but you don't know that the inside of this pipe might be like. Like an old car, it could be rusting away from the inside out.

I do not think there is any way i can dig out the entire line the concrete is just too thick (uou can see in the pic below). Towards the new location of the drain it looks to be over 6 inches. I'll do it if ihave to but i think the CI is in good shape as it was likely added in 1988 when the last owner did a ton of reno.

Ended up being a leaded in transition and i managed to drill and pry out the lead so now i can use a donut and transition to pvc. Pics attached. its hard to see but the trap goes on an angle toward the blue drop cloth in the pci.

I know the trap would be best under the drain but even if i put the new drain in the cent of the pan (32" wide x 60" long) the trap would be 8" or so away from the drain. I am leaning to moving to center the drain now as i want to use that Schulter preformed pan but am concerned about getting the stub out right which of course woul dbe easier if i had the trap under the drain.

I also found that the trap ties into the line into a CI hub so technically i could remove the CI trap and relocate but unless there is an easy way to melt the lead out i look forward to never having to take apart a leaded in fittng again!

 

[WorthFlorida]

There are tools you can rent to cut CI or you may have a cutting tool and cut the pipe past the joint. Then use a Furnco coupler to join the pipes. You must us a coupler with SS band around it. https://www.fernco.com/plumbing/shielded-couplings/strong-back-rc-couplings

If your are going to have it inspected because of a permit, the drain may have to be changed to a 2”. You may have to call the building department to determine if you have to change to a 2”. There seems to be a mix bag of opinions on this topic.

If you keep it at 1.5” and the shower drain is 2”, reduce it right at the drain before going down to the trap. Let it work like funnel. You’re not suppose to transition from a larger to a smaller pipe especially when it is horizontal. Use a standard shower head and not an enter wall of body sprays whereas you’ll overwhelm the drain.

Here is what looks like a 1.5” shower drain but I’m not sure if it will fit the cutout of a shower pan if you go that route. https://www.acehardware.com/departm..._Ux-xe7K9UQIPGHgYM4qLX3Q0d3q21IBoCUQUQAvD_BwE

 

[Claraarcher]

There are tools you can rent to cut CI or you may have a cutting tool and cut the pipe past the joint. Then use a Furnco coupler to join the pipes. You must us a coupler with SS band around it. https://www.fernco.com/plumbing/shielded-couplings/strong-back-rc-couplings

If your are going to have it inspected because of a permit, the drain may have to be changed to a 2”. You may have to call the building department to determine if you have to change to a 2”. There seems to be a mix bag of opinions on this topic.

If you keep it at 1.5” and the shower drain is 2”, reduce it right at the drain before going down to the trap. Let it work like funnel. You’re not suppose to transition from a larger to a smaller pipe especially when it is horizontal. Use a standard shower head and not an enter wall of body sprays whereas you’ll overwhelm the drain.

Here is what looks like a 1.5” shower drain but I’m not sure if it will fit the cutout of a shower pan if you go that route. https://www.acehardware.com/departm..._Ux-xe7K9UQIPGHgYM4qLX3Q0d3q21IBoCUQUQAvD_BwE

sorry if i am being a total noob here but are you saying the CI is a 1.5 line or the copper is or both? I measured the copper pipe diameter andit is 2" bu tmaybe hard to tell from the pics i posted.

If the CI is 1.5 i am in trouble - F#@%!#K

 

[James Henry]

Measure the diameter of the copper pipe you cut in half. if it measures 2-1/8", then you have a 2" drain.

 

[Claraarcher]

Measure the diameter of the copper pipe you cut in half. if it measures 2-1/8", then you have a 2" drain.

it is 2 in copper for sure. but looking at the inside of the CI below the hub part the diameter of the hole looks smaller than 2". The hub part acccepts a 2'x2" CI to PVC donut nice and tight, so would that make the CI a 1.5" ? The CI hub measures about 3" ID if that helps at all.

 

[James Henry]

try to get a measurement on the pipe where I put the arrow, I cant come to a conclusion from a picture. I wouldn't doubt if the whole drain was 2".

 

[WorthFlorida]

Could very well be 2". It just hard to tell from the picture perspective. Perhaps lay down a ruler next to it. Sorry I got you all nervered up over it.

 

[James Henry]

I'll do it if ihave to but i think the CI is in good shape as it was likely added in 1988

When you say "CI " I think you mean, "CAST BRASS".

 

[Claraarcher]

Could very well be 2". It just hard to tell from the picture perspective. Perhaps lay down a ruler next to it. Sorry I got you all nervered up over it.

the ID of the hole looks less than 2" and i confirmed with a

Could very well be 2". It just hard to tell from the picture perspective. Perhaps lay down a ruler next to it. Sorry I got you all nervered up over it.

here are some better pics. Hard to tell if it is 1.5 but tbh its been there since either 1968 or 1988 so i am not overly worried just would like to know for sure b4 i decide what to do.

 

[Claraarcher]

can anyone tell from the pics if its 1.5 or 2"?

other question is when filling the hole i assume putting a rock onder the bend is a good idea and filling with gravel / stone /sand is better than dirt? Will that help th CI last longer or wont matter as it may just rust from inside out overtime no matter what?

 

[Claraarcher]

ok so i managed to get the new PVC attached and relocated to thecenter of what will be a 32" x 60" shower. the issue i have now is the drain sits about 1 inch off the concrete slab (not glued yet) and if i am going to have a pre-sloped mud base with 1/4" per foot drop that makes the base under the liner pan close to 1 3/4 inch thick. then after the liner and mud base again it might be 4" thick? Given a 7.5 foor ceiling height i am not sure this is a good thing.

i cannot lower the drain pipe under the slab as i just barely got a decent pitch, so i would either have to move the drain to an odd location or do something different with the base.

I was thinking of a Schuleter base but not sure how much height i need from the 90 degree filliting that will accept attach the pipe to the kerdi drain. I also think that if i level the floor (should add less that 1/4" and use the pre-formed base i would have a much thinner base over all. As py drain location is just a bit off center (less than 1/2'' off) i think a can cut the pre-formed floor to accodomate with no issues.

The schuleter pan looks to be about 1 to 1 1//2 inches thick so that should work in this situation.

any advice on how i can reduce the current gap using a standard Oatey drian from HD if i decide to go with a mud base or, the lenght of pipe i need from the fitting to accodomate the Schuleter pan and drain is much appreciated.

thanks!