Install floor drain to existing drain

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Drmadef

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I would like to have a floor drain in my hall so it's easier to wash the floors
I have a radiant floor in a 4" slab. I had the concrete guy leave a 12x12 opening where I intend to put a floor drain in. I can see the 3" Pvc drain crossing under a corner of the opening but just barely.
It's not much to work with but if I cut a section of the 3" drain out by working under the drain and cutting upward toward the bottom of the slab, removing about 6", I figure I can attach a tight elbow on each end, then attach a trap on the end where the water comes in from the laundry, then attach a verticle T with 1 end coming straight up flush with the floor, (where the the floor drain is visible) and the other T end attaching to the water going out.

I cannot cut any of the slab for fear of hitting a radiant line. So all the work has to be done from the 12x12 hole to access the drain line.

Have I forgotten anything?

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How does a floor drain make it easier to wash a floor.

The first time your main drain backs up you'll wish you hadn't put that floor drain there.

Big design flaw of installing a floor drain in a home that is connected to the sewer system.
Water will seek out the lowest level outlet. FLOOR drain first choice. :eek::eek:
Next is shower and tub drain. At least those have a way to contain some fluid.
 
Washing floors using water and squeegee is done all over the world. Very effective on stone / tile etc. Not so common in America where cheap carpeting rules. That aside...I understand that water seeks its own level and my house is on a slight hill. So 1st would be how to test the level relative to the city drain line(?) There could also be a trap, or a one way valve as well as a sealed cap. So if I can get a response which explains how this floor drain could be done that would be appreciated. I think I need to: cut out a section-slide in a T with rubber connectors each side with clamps, then it’s finished with a 45 going to the floor surface?
Thanks
 
You will need a trap primer....no real good way of installing one now.

You can stop back ups coming through the floor drain if you have a back water valve installed, or one of those dinky mechanical flood checks in the floor drain itself, but I don't put much faith in those but it's better than nothing .
 
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The first time your main drain backs up you'll wish you hadn't put that floor drain there.

If there is clean out in the front yard that is substantially lower than the floor drain AND it has a loose fitting cap it will come out the clean out first. The loose fitting cap is key though, if the cap fits on tightly it may be able to withstand enough pressure to back up through that floor drain.

At work we have some ~ 6" round metal plates in the concrete floor which I think are covering access points to the outgoing drain lines. I have never seen the lid off one but suspect but there is a rubber seal between the plate and the pipe below it. There are 3 screws at the outer edge holding the plates on. Something like that might be better than putting in a 100% of the time floor drain (assuming doing so is legal in a house). Otherwise you need a trap to keep the smell from coming out of the drain, and the only way to keep it wet would be to pour water in from time to time.
 
real plumbers can afford to eat better than corndogs...2" or 3" but it may be too late for the nitrates to do any more harm.
Working in a 12" x 12" would be a challenge if the T was too long. Why wouldnt a T fit in the space with a 4" rubber boots on each side? Or is there another reason it wont work correctly.
We dont pay no nevermind to code here in NM. All the inspectors are cousins.
 
No disrespect, but have you ever tried working in a hole this size. It would be hard enough getting a sawzall in there
and cutting the pipe. Plus doing everything that you said would be a challenge to do.
 

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