Do you (would you) spray foam like Great Stuff directly on to PEX pipeing? Worried about chemical “problems”. Could wrap with tape or sleave it with poly pipe before sealing holes with spray foam. Think its stupid to worry about it? What if the foam somehow “interacts” and weakens PEX after 20 years?
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I'm always leery of spraying foam on any sort of plastic. I've seen what it does to finishes.
Spray foam has been applied directly to PEX since it was first produced to seal penetrations through framing and whatnot and it's never been listed as something to avoid.
Great Stuff around PEX pipe: better options
Dear Stormando and other FHB readers:
If you were planning to use Great Stuff around PEX piping to meet fireblocking requirements, think again: all versions of cured Great Stuff foam ignite at just 240 degrees F -- well below the ignition temperature of wood. This key fact is not included in DOW's MSDS documentation, however. You could use non-flammable fire sealant, e.g. 3M and DAP, which are sold by HD and Lowes.
Regarding the potential interaction of Great Stuff with PEX pipe, the non-flammable sealants are typically water based -- which would be safer from this angle as well.
I hope this is helpful if someone reads this post!
Mark