Ask Me Help Desk - No existing tee, what to add shower piping under concrete slab

Want to add a shower in our powder room, This is a concrete floor, piping is under the slab from a toilet drain. Assume piping is probably cast iron pipe. I was wondering what type of tee could be used for direct burial to tie in the shower drain with cast iron piupe. I called Fernco and asked them if there rubber type tees were rated for direct burial the answer was no.

Let me show you a typical wet vent installation in my area, (see image) STAY AWAY from any rubber fittings, NOT GOOD!
You will cut into the lavatory drain line using a PVC wye or combination wye and eighth bend. To instruct you fitting by fitting I'd have to have a diagram of what you have under the floor. Good luck, Tom

Tom,
Thanks for your quick response, The layout you had is almost exactly what I have now the sink & toilet are in exactly as your diagram. I wanted to add the neo angle shower in the exact location you have in your diagram . I altered your drawing to show what I have but can't figure out how to attach it. So I am going to try to explain. My existing sink drain is in the wall runs over to the vent (which runs up 2 stories through the roof,) down into the concrete floor and what I believe is going to be 4" cast iron pipe going over to the toilet and out into the main drain. (toilet and sink share the same vent). We have city sewer and the main drain to the street is in a laundry room which would be the next room on the other side of the wall at the top of your diagram. My original thought was to cut out a section of concrete and install a rubber tee then trap the shower drain into the tee with pvc. As I mentioned in the 1st. Email & you confirmed rubber is not the answer. I am not sure how I can tie the proposed shower into the cast iron pipe. My sink drain is in the wall, above grade. I can't figure out how to attach your drawing that I altered. Hopefully for me I explained how my exsiting piping runs.
Thanks,
Tony

Hey Tony,
Since you can't use the sink drain as a wet vent this adds a new problem to your project, Now you will have to run a vent on the new shower, That will present a bigger hassle the connecting the drain. I need a diagram of what you have and what you want to do here's how to do a attachment.

How do I add pictures and other file types to my post?
A. "Attach" files (including pictures) from your computer. This method puts the attached file below the text of the post.
Click on an Ask or Answer button to ask or answer a question
Compose your question or answer in the window.
Under the window where you composed your question or answer is a section called Additional Options.
Click on the Manage Attachments button: a pop-up dialog will open. NOTE: The Manage Attachments dialog lists the maximum sizes of the various types of files that may be attached.
Click the Browse button to navigate to the image on your computer and double click the file on your computer: this will return you to the dialog window.
Click the Upload button.
Click the link to close the dialog window OR repeat numbers 5 & 6 to attach another image.
B. "Embed" image(s) from the internet. This method inserts an image wherever you wish within the text of your post.
Click the Insert Image icon above the posting window: A pop-up asking for the URL will open.
Enter the URL of the image in the field then click the OK button.

How do I add pictures and other file types to my post?
A. "Attach" files (including pictures) from your computer. This method puts the attached file below the text of the post.
Click on an Ask or Answer button to ask or answer a question
Compose your question or answer in the window.
Under the window where you composed your question or answer is a section called Additional Options.
Click on the Manage Attachments button: a pop-up dialog will open. NOTE: The Manage Attachments dialog lists the maximum sizes of the various types of files that may be attached.
Click the Browse button to navigate to the image on your computer and double click the file on your computer: this will return you to the dialog window.
Click the Upload button.
Click the link to close the dialog window OR repeat numbers 5 & 6 to attach another image.
B. "Embed" image(s) from the internet. This method inserts an image wherever you wish within the text of your post.
Click the Insert Image icon above the posting window: A pop-up asking for the URL will open.
Enter the URL of the image in the field then click the OK button.
Back to you, Tom

Or you can use a combination wye and eighth bend. But coming off the main with a fitting is the easy part. You're going to hafta figure out a way to vent your shower since you can't wet vent it through the lavatory drain. Do you have the room to to roll a fitting up on a 45 and run a vent , either out the roof, revent back into a existing dry vent or run to the attic and revent back into a roof vent. And your thoughts? Tom

Quote:

Originally Posted by speedball1

Or you can use a combination wye and eighth bend. But coming off the main with a fitting is the easy part. You're gonna hafta figure out a way to vent your shower since you can't wet vent it through the lavatory drain. Do you have the room to to roll a fitting up on a 45 and run a vent , either out the roof, revent back into a existing dry vent or run to the attic and revent back into a roof vent. And your thoughts? Tom

Tom,
I altered your original diagram, the best I could with the software I have available here at work. As I mentioned in my previous email, the bath is exactly as your diagram, and the proposed shower will be added in the exact location as you shown. Only difference there is a 4" line running under the concrete slab, this is where the sink drain in the wall ties into along with the existing vent going up thru the roof. Hopefully the altered attached drawing helps show it better then I explained. At this point I thinky only dilema would be what type of wye or tee to use that if I cut the 4" cast iron pipe that I could slip on so I could add the shower trap & drain.

Am I mistaken or are you flushing your toilet into the shower? If that's the case wouldn't you b e be discharging a major fixture past a unvented minor one? Regards. Tom

Quote:

Originally Posted by speedball1

Am I mistaken or are you flushing your toilet into the shower? If that's the case wouldn't you b e be discharging a major fixture past a unvented minor one? Regards., Tom

No you are mistaken, the shower doesn't exist I want to add the shower. I redid the drawing to show how the piping system to this point. My only real question is if I cut the existing pipe that is under a concrete slab, what type of tee or wye should I use. I believe this existing pipe is cast iron, my nieghbor actually added the shower in his home, he cut and added the 4" rubber Fernco tee. His shower drains perfectly into the main system. I called Fernco and they told me there rubber type fittings are not made to be used under ground. I've talked to local contractors and they told me they use them all the time on septic systems etc.under the ground. To me the rubber type fitting seems to be the only logical way to tie into this piping without jack hammering up half the house. I do know in older days they used to pack & fill cast iron joints with lead, there is no way this can feasibly happen for me. I am going to need some type of tee or wye that can slip over the cast iron pipe after I cut a section of it out. Just not sure of what that fitting should be.

Can you draw up your existing drainage, Your last two drawings show the toilet discharging directing into the shower, N ow you've added a main drain in the last drawing but still show the toilet discharging into the proposed shower, I could buy this if you didn't have two drain lines running from the toilet. I got to be missing something here, What is it? Back to you, Tom

Quote:

Originally Posted by speedball1

Can you draw up your existing drainage, Your last two drawings show the toilet discharging directing into the shower, N ow you've added a main drain in the last drawing but still show the toilet discharging into the proposed shower, I could buy this if you didn't have two drain lines running from the toilet. I gotta be missing something here, What is it? Back to you, Tom

The drawing does depict the existing drainage, minus the proposed non existing shower to this point.The pipe that is shown running over to the area where the shower is proposed to be installed is already there(existing). I believe the toilet discharges into the main drain to the street (probally lower than the pipe that is running over from the toilet to pick up the existing sink) I don't know exactly how they tied it all in because it's all under the slab. I do know on floor level in our laundry room which is on the other side of the bathroom wall the main drain has a wye clean out plug at grade level. I am not really concerned on it working it will, when these houses were built some of them had the showers installed as an option. This one didn't. My only question is what is an acceptable fitting(Tee/ or Wye) that can be installed in the existing pipe that's there with major piping modifications. The homes that came with the showers already installed back in 60's had the tee & wye already installed under the slab with the 2" drain coming up through the slab(which is copper as is all my piping throughout the house. I do thank you for all your effort & time with responses, I really don't know how to explain it any better , without a 3d cad program , I really couldn't show it any better. On a different note how do you like Fla. Was looking to retire myself down there soon, We were looking to add that shower to make the house more sellable. We were thinking to moving to the west cost north of Tampa.