PEX Lines expand/contract in joist and Squeak!

Old 03-09-16, 01:19 PM
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PEX Lines expand/contract in joist and Squeak!

Have everything running fine for the last month or so!

I had replaced the copper water lines, used orange PEX so I could raise my ceiling in the basement. Drilled holes for the lines in the joist which worked perfect until the "ghost" showed up!

When the PEX lines expand slightly when the boiler kicks on they move slightly, slightly rubing against the wood/holes. This results in a squeak/crackle sound.

Tried to put paper between the pipe and holes....still makes the sound.

Is there any type of expansion fitting of some sort I can use?

Thanks for your advise!

Old 03-09-16, 01:28 PM
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A little talcum powder works for wood floors, might be worth a shot here.
Old 03-09-16, 01:42 PM
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Any way to make a loop with a new piece and a couple of connecters near where the line goes through the first joist?
Old 03-09-16, 01:51 PM
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Hind sight is 20-20, but why did you drill too small holes. Larger ones would have allowed movement.
Old 03-09-16, 06:56 PM
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yep, common problem.
we insulate the pex lines and that allows the pex to grow when it gets warm
Pex has a much greater thermal expansion then copper does (which is predictable), and this causes the pex to tick and rib in the joists.
Outdoor reset helps, as it limits the water temperature closer to what it is when the system is off an d idle.
Constant circualtion also helps by reducing water temp swings and rate of cooling and heating.
it's your choice, but everything I suggest results in a more efficient system
Old 03-21-16, 10:41 AM
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I don't know if it was for copper touching creaking or pex. Somebody had suggested some slip collars made from milk jug strips so it slides easier. The barrier on heating pex gets a little sticky.

Check page 9 on link. Pex expands (and contracts) 1" for every hundred feet for every 10 degrees.

I had a 30 foot run installed at 70 degree temps with no slack/loop to allow for expansion.Heat turned on and baseboard section connected at a 90 through wall pushed out 3 inches from the wall .

Changed how it connected in basement, put in slide hanger version clamps instead of talon clamps and put a loop in. Still creaks a bit but baseboard not moving.

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