I have a 50 year old home containing 4" cast iron sewer pipes that connect up to concrete pipes about 3 feet past the foundation. The concrete sewer pipes then run about 50 feet to the city sewer system. Where the CI pipe connects to the concrete pipe, there is a concrete wye. I have recently had some problems with backups in my basement which have been determined to be caused by tree roots right in the area of this concrete wye. I have removed the trees and need to remove and replace the concrete wye to effectively remove all the tree roots from that section. Is is possible to replace the concrete wye with a PVC wye? I don't think I will have a problem connecting the PVC wye to the cast iron (house) side, but I'm not sure if it is possible to connect the other end of the PVC wye to the remaining concrete pipe that runs to the city sewer. How do you connect 4" PVC pipe to 4" concrete pipe?

I can think of a couple ways to do this Nastymage...

Best choice will probably be to purchase a FERNCO coupling from a PLUMBING SUPPLY HOUSE.

The reducing FERNCO coupling (see picture) will allow for the transition from the concrete to the pvc pipe.

You will need to measure the DIAMETER of the concrete pipe and then order that size by 4" cast iron fernco coupling.

These clamps are designed almost exclusively for underground connections and should do a great job for this project!

Let us know if you have any more questions...

MARK

The "Y" is your clean out. Install PVC clean out and terminate it with plug at the ground level. Proceed as suggested by Mark.

Here is a picture of my sewer line as it leaves the house. The pipe at the top, exiting the house under the foundation is cast iron. The wye in the center and the pipe heading away from it to the lower left are both concrete.

Hi Nastymage:

Pic. Is good and clear... thanks.

Plan on cutting the concrete pipe with an angle grinder with a diamond circular blade... see pic. Below. Wear goggles and a dust mask can't hurt! Plan on digging that hole UNDER the concrete pipe a little deeper here!

Cut the cast iron pipe by renting a cast iron chain cutter.. see pic. Below... (wraps around pipe, connects, tighten, and then use lever to apply pressure and *SNAP* pipe near to the concrete fitting. If pipe crushes then you may need to get a sawzall and some LENNOX DIAMOND sawzall blades and make a cut through the cast iron.

Then purchase the reducing fernco and an additional cast iron clamp and you should be all set. The cleanout is also a good idea.

Let us know if you need more info... ;)

MARK

How much of an angle does the line have to have?