I am adapting a 4” cast iron hub to either 3” or 4” PVC. I currently cut the cast iron flush with the hub. The cast iron is 4”. I was not able to leave a stub out for a no slip band clap. I plan on getting the balance of the cast iron pipe out of the hub. I wanted to know what I can use the seal the joint between the hub and new PVC If they even make such a thing. It’s the vertical stack that goes from the crawl space to the interior of the house. Is this what I need and is it the best way to go? https://www.homedepot.com/p/Fernco-...0-PVC-Compression-Coupling-P44U-405/100372279 My plumber will be running the remainder of pipe through out the house. I am repairing the foundation wall and want to get this sorted without having him come out as the pipe runs right next to it.
That should work.. Those things kick ass. Just make sure it's the correct one when you pick it up. I think I used grease or something on mine too get it to work too. The fit is tight.
was just going to say fernco is what you want, when i read the title. good to see you already found it.
Like said - Fernco is the answer. They make different sizes for different pipes. Call a plumbing supply house like First Supply or Ferguson and speak to the service counter. They’ll set you right. If it’s REaLLY old, like from the early 1900’s measure the OD of the pipe. Sometimes we run into pipe that’s just a bit different than modern sizes. Edit - your HD link is what you need
Why do I feel like 4" pvc will fit right in 4" cast iron pipe, with a little persuasion, and fit tight as a bugs ear?
its been a while since i forced one in there (giggity) but you would need to really get heavy on the sand cloth to remove a couple hundredths of an inch off the pvc to make it slide in.
I've stacked toilet flanges that way. I think a 3 to 4 works. Or something like that. Lol... I'm a woodworker....
Just to add a little...Fernco even has an app to help you select what you need. I’ve used all different sizes, up to 12”...they work great.
