Copper pipes have to be sleeved where they come through the slab, and in most new houses they sleeve the entire pipe length with plastic. It looks like yours do not have any sleeves, so I'm guessing its been there a while.

Slab leaks are always a PIA, and I think this is a good time to reroute and get it all out from under the slab. It will take you a little longer to route the new PEX, but will be much easier to maintain in the long run.

Try to find a plumber who likes PEX and does not try to run it exactly like copper lines (which usually have all kinds of branches and T fittings). I recommend running a 3/4" line to a PEX manifold near/in the bathroom and then running 1/2" individual PEX lines to each fixture. It makes it really easy to shut off the water to one fixture at a time when you need to troubleshoot or replace anything.

When I had my basement bathroom ceiling open for renovation I also had access to the 3/4" copper lines running to the kitchen above and to another bathroom on the 2nd floor. I connected those main supply lines to the PEX as a 3/4" pass through with a ball valve shutoff so I can turn off the kitchen or upstairs bath from the manifold in the basement. I can't shut off individual fixtures in the rooms above, but I can shut off the entire room to fix the plumbing.

Bruce

Thanks Bruce. I’m planning on T-ing from the water heater 3/4 straight to the bathroom. The manifold option sounds like good idea! I’ll just have to cap under the slab for now until I have to do a complete re-pipe.