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pex or copper in concrete?

tonyk Member Posts: 12

I have a boiler with base board heat. There is a  4 ft. piece of copper pipe which is buried in the the concrete slab in the area under my front door. It has developed a  leak and I was wondering if it is better to use Pex or stick with the copper.  I will be recovering the pipe with concrete when the leak is repaired.

Also, if I use pex are Shark Bite fittings a good way to connect to the existing copper pipe.


  • Gordy
    Gordy Member Posts: 9,546

    In concrete is better. All though copper lasts a long time, pex will outlast copper with the use of fly ash, and other chemicals in today's concrete mix its hard on copper.
  • Steve Whitbeck
    Steve Whitbeck Member Posts: 669

    PEX is better but for a short run just run the copper pipe inside a rubber hose to keep it off the concrete. That way you don't have to buy any special connectors.
  • tonyk
    tonyk Member Posts: 12
    Pex or copper

    If I use pex, or copper should I cover it with a hose? or I was thinking about using pipe insulation or some kind of foam wrap to allow for expansion and to insulate it from the concrete
  • hot_rod
    hot_rod Member Posts: 21,872
    pipe wrap tape

    would be fine, insulation would give you a hollow space in the concrete.

    Most plumbing and HVAC suppliers have this tape.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Ironman
    Ironman Member Posts: 7,350
    Shark Bites...

    May be okay if the copper is clean and not out of round. Personally, I wouldn't do it. I'd go with the appropriate press fittings. Pex moves form thermal expansion and contraction and may cause an issue with the O ring in the long term.

    If it were accessible, that would be a different scenario, but considering the possible cost of redoing it, I'd go with a proven method. If you don't have the tools, you may want to hire a pro.

    Also, make sure that you use o2 barrier pex. It does make a difference.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Paul48
    Paul48 Member Posts: 4,469
    Pex & Connections

    No buried connections.
  • tonyk
    tonyk Member Posts: 12
    Type L copper

    If I use copper, I was thinking about using coil that way no joints under concrete. If I go that route, would type L be OK? or would I have to use type K
  • Steve Whitbeck
    Steve Whitbeck Member Posts: 669
    Use L

    L would be just fine.

    I remove old leaking piping and install new L copper pipe. I insulate the pipe where it may contact the concrete.
This discussion has been closed.