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Should I be concerned about this PEX and UV?

Javelin Member Posts: 138
Heating Pros,

I've read the various older posts, but am looking for some concrete answers here. I've recently run 3/4" PEX feed up to a bathroom. In is up in the joist bay in the basement, but near it is a CFL bulb (which I'm told gives off some UV rays when on). Then, it goes by a window where it's not exposed to direct sunlight, but certainly indirect at certain times of the day.

My question is do any of your pros have experience/clients who have PEX run in unfinished basements that have seen failures? Or is it really a direct-SUNLIGHT only issue that I don't really need to be concerned about in my unfinished basement?

Thank you in advance for any words of wisdom!



PS - you'll see in the one photo, I've started covering the PEX with foam pipe insulation (because I was scared). Is this prudent and if so, enough to protect the PEX?


  • icesailor
    icesailor Member Posts: 7,265
    What? Me worry?

    If you are worrying about what you describe happening, and causing a disaster, fear not. If something does happen, you won't be alone with the problem. No one else wonders or cares. So, its a non-issue.

    I once ran PEX under a deck to an outside shower. I worried about the sun shining through the spaces between the boards, shining on the pipes. I worried about being bitten by spiders, ticks, Poisonous snakes. I've been bitten by ticks more times than I know, Never by a spider or a snake.

    Sit back and enjoy an adult beverage.
  • hot_rod
    hot_rod Member Posts: 19,860
    go with the manufacturers advice

    I have seen the non colored, barrier pex go bad when left under a job trailer in partial sunlight for just one summer. It became very brittle and discolored.

    insulation, or latex paint if permitted, would give you piece of mind.

    Some solar contractors put a coat of latex paint on the UV coated, exposed solar foam insulation for additional Uv protection, it does make a bid difference on the life expectancy.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • bill_105
    bill_105 Member Posts: 429
    My take on it was...

    Farming out there?:)
  • RobG
    RobG Member Posts: 1,850
    Cover It!!

    Absolutely, cover it. Pex will get brittle if exposed to UV. Cover it and tape the joints in the bends (that's where it has the most stress).

    Seen it, had it happen, not pretty.