Hot & Cold in the slab

JustinBcareful

I know O-barrier radiant piping is designed to go in concrete, but I have an island that needs hot and cold pex to the sink that will be buried in the concrete. Do I need a special type or encase the pipe in something else?

JUGHNE

Often it is wise to install two 2" PVC conduits with the standard sweeps from under the island to somewhere above the concrete. Be it inside a wall, crawl space or basement.

Good for future replacement if needed or perhaps filtered water line. 2 pipes will insulate the hot and cold from each other.

Cheap insurance at this time. IMO

GroundUp

The O2 barrier is to protect the internals of the heating system from O2, nothing to do with the concrete. You would use regular non-barrier tubing for domestic hot and cold to the sink, but as was mentioned I would put a sleeve of some sort in the concrete should the tubing need to be replaced or manipulated some day

hot_rod

You can buy pre-sleeved pex, or buy the sleeve material separate.

1/2 pex should easily fit inside 1" PVC. Make a nice curve to PVC by warming with a heat gun, or very carefully with a torch.

Electricians have PVC heaters to make bends and offsets in PVC.

Hopefully it is a short run, if not insulation would help speed HW delivery.