I have a Cast iron floor drain, it does not go underground, it end with a clean out on the side of my basement

I have an old house (build around 1949), it has an existing concrete platform with shower and Toilet (without wall) - Refer to attachment 1

We hope that we can bring the shower and toilet lower then where it is now
We have break the concrete platform - built with sand, concrete and stone
We notice the exiting cast iron is really not in good conditions which need to replace (attachment 2)

We wonder what other option we have in order to build a new bathroom without using water pump or upflusing toilet

We were thinking on getting a Back /Wall flush Toilet which we should be able to bring down the toilet close to the ground but we still unable to find a solution for Shower.

As the shower will required a P-Trap, I wonder how close we can bring the shower to the group, what is the height of the new platform we need to build? How much minimum space needed between Shower drain and bottom of P-Trap?

We also have a Bathtub drain with vent from First floor coming down to basement next to the basement toilet

Thanks in advance for any possible advice

NJ, US
Wendy

First thing I would do is cut that 4 inch cast iron pipe and reduce it to 3" pvc pipe (cut with sawzall and 8/10 teeth per inch sawzall blades and attach onto cast iron with a 4" shielded band clamp (see pic.1) ) and then attach to cast iron with a 4" dandy cleanout (see pic.2) and a 4"x3" reducing bushing in the end of the dandy cleanout...now ready to do some plumbing!!

Then there is not much else you can do...the idea of backflush toilet is good idea...with pipe reduced to 3" pvc you may in fact get the toilet to sit on floor.

Pipe that 3" directly over to toilet...end the run at the toilet. Then from behind the toilet fitting install a 3x2 wye and run 2" over to the shower drain. You will also install a 2" wye fitting just before shower ptrap that will act as a vent for the shower AND the toilet. This 2" vent should connect full size into 2" vent or larger in house (can be run up through closet if necessary).

I see no alternative but to raise the shower floor here.. but may not need to go as high as you think...

The ptrap for shower will determine the finished height of your floor... the stub out of the trap is adjustable... so you will install the ptrap and then measure to the top of the ptrap, and then install joists so joists clear the ptrap plus an inch... then install floor and then install the shower base (in bed of mortar) and cut the pipe from the shower trap to shower floor as needed... final drain height cannot be established until unit is in place and shower strainer is in place.

You also have another 2" pipe over in corner of picture.....what is it picking up? That will need to connect into the 3" pvc pipe as well (3x2 wye here).

That is my thoughts on this at this time... get back to me with any questions... MARK

Thanks Mark...

- The 2" pipe is coming from Utility sink on the side of the house and also coming down from Kitchen sink from the main floor (pic 1)

I think on having the basement shower, toilet and sink ‘s vent tap into the vent pipe from the bathtub’s vent from the main floor, is that approve by code? (pic 2 – Bathtub vent from main floor)

Pic 3 is a closer look on Bathtub drain and vent from main floor, the vent going up to the roof

Thank you.

As long as bathtub vent is 2" vent upstairs, you can tie your 2" vent from the basement bathroom into it upstairs at least six inches higher then the floodlevel of the sink (just means to connect downstairs vent into upstairs vent at approximately 45 inches off the finished floor).


I did not know sink was going here, too. (makes sense, of course.. ;) ) So, here, on that two inch pipe that goes to pick up shower and that 2" wye I mentioned for shower vent....just take that 2" shower vent and use it as the waste line for the sink... it will also act as a wet vent for the toilet and shower and as dry vent for the sink (one vent system)... that all make sense?

Then run that 2" vent to upstairs tub vent (must be 2" though)... let me know your thoughts... Mark

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