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jimmydale
Jun 30, 2008, 05:25 AM
I am putting a bathroom in the basement using PVC for the drains and copper for the water. I am also using PVC for a drain by the rear entry of the baement. There will be 4" of cement on top of the PVC.

Would there be any kind of problem using PVC in this application? I have tile going to the main - I just want to use PVC for the drains to the main.

I am not sure if the PVC will eventually crack from pressure - and I get conflicting info. **SOME PEOPLE ARE TELLING ME TO USE CAST***

Thanks for your help!

massplumber2008
Jun 30, 2008, 05:33 AM
Hey Jimmy...

Absolutely no issue with using PVC underground...ok??

In your area it could be PVC or ABS piping (check to see what is approved in your area by calling local inspector and simply asking him what is approved for underground drainage piping in your area)... both are plastic type pipes and are accepted for installation underground everywhere, residentially!

Just don't put the PVC or ABS pipe/fittings into the cement.. will expand/contract and could crack your concrete. So that is only issue you should be concerned about... ok?

Let us know if you need anything else... ;) Glad to help with drain/vent questions... anytime!

MARK

Milo Dolezal
Jun 30, 2008, 05:37 AM
You selected right materials for your project.

PVC pipe is OK in under slab installation. We always wrap it with Foam Wrap materials. This way there is a separation between pipe and concrete. Since it is used for drain, there is no pressure on the wall of the pipe. Also, it is covered with concrete that will protect from possible damage from the outside. Every PVC brittles and eventually cracks, but you are many (many) years away from dealing with this problem.

speedball1
Jun 30, 2008, 05:37 AM
I am putting a bathroom in the basement using PVC for the drains . There will be 4" of cement on top of the PVC. I am not sure if the PVC will eventually crack from pressure. Would there be any kind of problem using PVC in this application?
Not to worry! We have been using PVC drainage under the slab for years without a single complaint about Schedule 40 PVC breaking down.

I get conflicting info. From who? Certainly not from a plumber. Good luck, Tom

speedball1
Jun 30, 2008, 05:52 AM
Every PVC brittles and eventually cracks,
Milo, Is this a problem in your area? Could you giver me the source of your information? Regards, tom

massplumber2008
Jun 30, 2008, 09:57 AM
Jimmy.. also note here that if pipe won't be IN the slab... there is no need to wrap PVC pipe in foam wrap or anything at all for that matter... ok?

Just so Jimmy was clear on that point... ;)

MARK