Cast Iron Drain

I own a 40 year old home, which is on a slab and am currently remodeling the master bath. The entire bath has been gutted from floor to ceiling and to include the wall that houses all piping and venting. After removing the tub I attempted to remove the tub drain/overflow which broke off. Thinking that the 1-1/2" drain was bad (corroded) I rented a jack hammer with intentions of
opening the slab back to the main vent. After removing approximately 6 to 8" of the slab I found that the line transitioned to 2-1/4" O.D. cast iron with a cast iron adapter that transitioned to the old p-trap. Knowing now that the line is in fact 2" I will go back whith my original plan of installing a shower in lieu of a tub. My questions are:
1. Due to availability I would like to install a center drain base. Should I cut the slab in an effort to achieve a more direct line to the main drain and install a 45 ell. Or should I cut to my existing rough in and install a 90 deg ell and then connect to the cast iron. Either way the drain would be no more than 5' to the main drain.
2. Should I just cut the cast iron behind the coupling and tie in pvc, if so what is the appropriate fitting to do this transition. It will be buried in soil beneath the slab.
Thanks in advance,
Rick

I would cut on the stack side of the coupling. Then get a snake with a 2" cutter head and snake the line to be sure it is open 2" all the way to the stack. Then get the fernco with just the 2 stainless hose clamps and complete the drain.

How far are you from the coupling to the stack?

That will determine leaving the CI pipe or busting up the floor the rest of the way and replacing it all.

Either way will work

its probably ok whichever way you decide to do this

it was already up to code long before you started this project

its 2 inch in the slab and will be ok,

if you want to break up some concrete and cut it off
and make it more stream lined

I say go for it..... breaking up concrete is good exercise......


Either way--Just dont put too many mean bends

in the line or you might not be able to snake it out later on

Cass said:

I would cut on the stack side of the coupling. Then get a snake with a 2" cutter head and snake the line to be sure it is open 2" all the way to the stack. Then get the fernco with just the 2 stainless hose clamps and complete the drain.

How far are you from the coupling to the stack?

That will determine leaving the CI pipe or busting up the floor the rest of the way and replacing it all.

Click to expand...

The coupling is 24" from the stack, I have exposed another 6" of the line and it appears to be in good shape externally. There is alot of congestion there at the stack (water lines, etc) and I would prefer to avoid a total replacemenrt unless needed, I will snake per your suggestion for sure. The only issue I see now would be the angle to the new rough opeming for the center drain, it will probably be about a 60 degree angle. Will the pvc have enough flex to compensate for that.
Thanks for the help!!!
Rick

You don't want to try to flex PVC anywhere near that much! You should be able to use some 1/8th bend fittings, or a 45 and and 1/8th to get things where you want. There is a little bit of give available when you glue up the fittings,and a small amount of flex acceptable to fine tune things to get it exactly where you want (and the Fernco will flex a little). You don't want the Fernco to flex much, though, or you'll be providing edges that can catch hair, etc., and create a clog down the road. You really want that to be installed and supported prior to backfilling so it is straight.

If you are going to tile the new shower, you might want to check out www.johnbridge.com . Also, there is a slick shower system by www.schluter.com highly recommended that produces a tiled shower with some impressive credentials and features that is quicker and easier to install than older more conventional methods. It basically uses a waterproof membrane and special drain that makes the entire substrate of the shower waterproof (most shower walls are only water resistant, and there is a lot of the floor that can retain moisture above the waterproof pan). In fact, they warranty the construction and recommend you build the shower walls with plain drywall (rather than cement board). This system has been in use in Europe for a long time, and here for over a decade. Check it out.

Cass said:

I would cut on the stack side of the coupling. Then get a snake with a 2" cutter head and snake the line to be sure it is open 2" all the way to the stack. Then get the fernco with just the 2 stainless hose clamps and complete the drain.

How far are you from the coupling to the stack?

That will determine leaving the CI pipe or busting up the floor the rest of the way and replacing it all.

Click to expand...

Thanks so much for your response, however I have exposed another issue
Something did not look right with this drain, so I have now exposed the line to the vent stack and found the drain elevation to be good but in the WRONG
Direction. All I can assume is that the Slab has settled. I cannot see it to well
but it appears that there is a 8 degree or so fitting connected to the vent pipe and the 2" drain is of course connected to that. Should I cut as close to the ell and install the fernco there. I am concerned about the deflection of
having to compensate for the bad angle and giving myself the correct angle.
Thanks,
Rick

You need to have 1/8 - 1/4" per foot of fall from the trap to the stack.

Get as close to the stack as possible and be sure to ream the hole out going into the stack, this builds up with crud over the years and can be restricted down to nothing. Some times you need a small chisel and hammer to do it.

Cass said:

You need to have 1/8 - 1/4" per foot of fall from the trap to the stack.

Get as close to the stack as possible and be sure to ream the hole out going into the stack, this builds up with crud over the years and can be restricted down to nothing. Some times you need a small chisel and hammer to do it.

Click to expand...

Thanks, What fitting should I go with to tie the pvc to the cast iron. I have already purchased a fernco with the ss outerband. Should I use that or just the rubber sleave for flexibility and contact with the soil.

Thanks Again,
Rick

The banded coupling is for above ground instlation and the rubber coupling is for in ground instlation.

coupling

In this area the banded coupling is used above ground, or below, inside the building the all rubber one is only used outside underground.