Does slab on grade = cracked pipes?

[topograph]

Thought I had read a post from someone stating that bringing your waste lines through the slab was an invitation to cracked pipes down the road; post & pier isn't an option, since this is for a workshop that needs to have vehicular access. Thoughts?

[Carey]

Our house slab was poured in the early 70s, ABS drain lines show no cracking (copper supply lines did fail in slab & were replaced with above ground cpvc prior to our purchase 9 years ago...)

ADD: the in slab drain lines went through the '75 & '06 earthquakes...

[Rob Tucker]

Proper installation of pipes in a slab will have those pipes wrapped in (preferably) foam to keep a flexible surface between the pipe and the concrete. I would recommend a 1/2" thick wrap. It is also good practice to use a stainless steel clamp and SS mesh on the pipe in the concrete as a termite barrier. The SS mesh should embed into the concrete. Any penetration of the concrete is a potential route for termites.

As much as possible you can also try to keep the pipes on the exterior perimeter and not in the concrete at all. We don't have freezing conditions to worry about. A leaking water line under a slab can be a real pain in the neck.

But to answer your question: Slab on grade does not = busted pipes. There are millions of homes on slabs without plumbing problems. It is primarily a factor of workmanship.

[Seeb]

But if they do leak it's a pain in the butt to deal with.