Copper-to-PEX Transition Under Slab

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New Member
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Flagstaff, AZ
I've got some copper lines I'm thinking of extending another 24" into a nearby wall. I'll need to extend those lines via an approved under-slab connection method (thinking Viega ProPress). A local plumber has the necessary tools and can probably install 4 fittings in less than hour. Once above floor level, those lines will need tied back together in order to feed another fixture down the line. Currently, there is one 1/2" and 3/4" line for cold, and the same for hot. The 1/2" lines feed a garage sink 8' away.

Should I go copper-to-copper, or copper-to-PEX?

I've got ProPex Expansion tools, and plenty of fittings already. Nothing for copper (nor much in the way of sweating skills.)

ProPEX EP fittings are under-slab approved, and so are ProPress Fittings. Really, the only reason I'd transition from copper to PEX is because I've got the tools to work with PEX. If I didn't do it under the slab, I'd do it in the wall where the extended lines exit.

Jeff H Young

In the Trades
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whatever you feel is best to bring it above floor . Id probebly go with the copper till above ground since youve got existing already there.
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