Hi - I'm running water into a shed under the foundation footing and up through the concrete floor. I read in the international residential code book that pipe under a foundation or through it needs to be protected with a supporting arch or pipe sleeve two sizes bigger than the water pipe. I can't seem to find much about this and in some of the plumbing books (e.g. black and decker) they seem to run pipes right in the concrete. So, is it necessary to pass inspection and, if so, what is a pipe sleeve exactly? Thanks!

Depends on what code your inspection people use. A pipe sleeve is nothing more than another piece of pipe, bigger than the supply size that is placed over the supply. That way, the crush weight of the ground or foundation is on the sleeve, not the supply.

In my area you cannot run PVC under slab. However, if you have to run it through a foundation wall than run it through a larger sleeve ( larger diameter piece of PVC pipe inbeded into concrete before pour ). For instance: if you are running 3/4" Schedule 40 PVC than run it through 1 1/4" PVC sleeve.

However, see if you can somehow run it through framing ( wall and ceiling ) so you don't have to go under concrete. There is always a way to do so...

Back to you... Milo

Thanks. Should anything go inside the sleeve between the inner and outer pipe?

According to code you do not run pvc pipes under footings of a foundation because of ground settling. You are allowed to run parallel with a foundation with a distance of 2' and at a 45 degree angle. Also you are not allowed to run pvc pipes under slabs as well. Others such as copper, cpvc,and galvanize are permitted. I hope that answers your questions.

We sleeve all pipes, with a larger sized pipe, that run through or under the foundation an we sleeve with Armoflex all the stub ups and manifolds that come out of the slab
I'm looking at two posts that are telling me you can't run PVC under the slab. Although you didn't say does that include drainage as well as water pipe?
Back to you, Tom

Sleeve is only a spacer. It is there to keep concrete away and to create space for the pipe. Therefore, it can be in direct contact with concrete.

As per Tom's comment: It is OK to run non-pressurized PVC pipe (drain) under concrete slab.

Its just the water supply going into a pressure tank, no drainage.
So can the sleeve under the foundation be PVC?
Is there any thing in the sleeve that packs around the inner pipe?
Its OK to concrete right up against and around the armaflex?

amb922-my well supply and power cable run through a wall spacer that is filled with silicone caulk. Been there 10 years, about 2 ft. underground, never had a problem. Brian ma0641

Yes, DWV pvc is allowed under slabs.
PVC water lines are the exception.