Convert cast iron closet flange / elbow to PVC

[pemurph]

Hello,

I am trying to convert my closet flange / elbow to pvc. I initially was going to unscrew the galvanized steel from the cast iron elbow but it broke off inside the threads. Since that happened, I cut the cast iron right before it Wye'ed to the bath tub / sink drain. I have found that the length of a 4 inch elbow plus 4 inch to 1.5 inch tee for the bath / sink drain extends the flange out too far. Is there a pvc fitting that has the 1.5 inch Wye integrated into the 90 degree elbow ? Any suggestions for how I can accomplish this , or complete this task in another way ?

Thanks in advance.

Pat

 

[hj]

Nope. You have/had a "tapped closet bend' and they have been illegal for decades.

 

[Sponsor]

 

[Erico]

Hello,

I am trying to convert my closet flange / elbow to pvc. I initially was going to unscrew the galvanized steel from the cast iron elbow but it broke off inside the threads. Since that happened, I cut the cast iron right before it Wye'ed to the bath tub / sink drain. I have found that the length of a 4 inch elbow plus 4 inch to 1.5 inch tee for the bath / sink drain extends the flange out too far. Is there a pvc fitting that has the 1.5 inch Wye integrated into the 90 degree elbow ? Any suggestions for how I can accomplish this , or complete this task in another way ?

Thanks in advance.

Pat

Can you cut further back toward that hub? Or remove the cast from the hub and use a donut to attach to the hub?

Are you above finished space or a basement?

How far out does the y and elbo put you? Would an offset flange work to get you more in line? You can pick up 1.5 inches with the offset flange.

If you are installing a new toilet maybe get one that accommodates 14" rough in?

 

[pemurph]

Can you cut further back toward that hub? Or remove the cast from the hub and use a donut to attach to the hub?

I can cut further back towards the hub. I could also remove the cast from the hub and use a donut, I have never done this and I am kind of afraid to cause a bigger problem than I already have. I have also heard that donuts are harder to install / more prone to leaks. As far as I know you just heat up the cast with a torch and hit it with a hammer until it breaks free. Is that right ?

Are you above finished space or a basement?

I am above finished space, but I can take out the drywall ceiling below if I have to.

How far out does the y and elbo put you? Would an offset flange work to get you more in line? You can pick up 1.5 inches with the offset flange.

I don't have the exact measurements on me ( I can get them). I have a 2 inch shielded fernco fitting and a 4 inch unshielded fitting. Is the 2 inch right for this application ? That could save me some space. I am not familiar with offset flanges, but looking at pictures it looks like that would require more space than a 90 degree elbow. Or maybe I am thinking of it wrong and the offset flange goes in the opposite direction to pick up space.

If you are installing a new toilet maybe get one that accommodates 14" rough in?

I am installing a new toilet I can buy whatever works

Thanks for any help.

 

[Erico]

I am installing a new toilet I can buy whatever works

Thanks for any help.

Ideally you would re-work the sink and tub drain if you can access the stack below the bathroom - easier if there is non finished space below. Also, what is above and where could you vent the new tub and sink drain?

To mimic the old setup with the tapped closet bend you will need to take out the entire old closet pipe/elbo and attach PVC to old cast iron hub with a donut

Even then, your ultimate rough-in distance from finished wall may be more than the desired 12 inches. If so, you can make up 1.5 inches with an offset toilet flange. Or you can get a brand of toilet that allows for a 14 inch rough in - I've used Toto in the past.

Not sure if the pros here would recommend using both an offset flange AND a 14 inch rough in toilet. I don't see why not.

I had a similar predicament here several years ago. I was adding an extra bath to my condo and had no access to the stack above or below. We added a Y similar to what you are considering and ran 4" PVC across the hall. Not really ideal but it still works great 6 years later.

I ended up with a 14 inch rough in so I purchased a Toto that accommodates 14 inches.

You will have to play with a couple scenarios and see how your measurements come out. Get it close then make up the difference where needed.

 

[pemurph]

Ideally you would re-work the sink and tub drain if you can access the stack below the bathroom - easier if there is non finished space below. Also, what is above and where could you vent the new tub and sink drain?

To mimic the old setup with the tapped closet bend you will need to take out the entire old closet pipe/elbo and attach PVC to old cast iron hub with a donut

Even then, your ultimate rough-in distance from finished wall may be more than the desired 12 inches. If so, you can make up 1.5 inches with an offset toilet flange. Or you can get a brand of toilet that allows for a 14 inch rough in - I've used Toto in the past.

Not sure if the pros here would recommend using both an offset flange AND a 14 inch rough in toilet. I don't see why not.

The stack below is drywalled. The existing galvanized piping vents up above the sink drain to the roof for the tub and the sink. I removed the galvanized and planned to replace with 1.5 inch pvc using a fernco to connect pvc to the existing galvanized going up from the sink. I was told I only needed to replace galvanized pipes that lay horizontal and had water sitting in them because they rust from the inside out. I was told vertically oriented galvanized was ok to keep due to water not resting in them as well for vertical vent pipe. I think if I rip out the existing cast and use a donut it will fit. I just read you can drill out the lead. I might try that if that is the only option

 

[Erico]

Yeah, the galvanized vent should be no problem keeping and tying in.