Is great stuff ok on ABS pipe

[KiviP]

I think I pretty much know the answer but would regular foam be harmful to the pipe or put pressure on it? I have 2 drain lines going into the attic kneewall ans want to seal around it. I have foam core ABS. Just being pedantic and it should be safe on plastic but I was wondering if I should get lowe expanding rather than regular gap foam

 

[Breplum]

should be ok

 

[Sponsor]

 

[WorthFlorida]

Local code may require a fire barrier foam between floors. Not to clear with your question "attic knee wall", but fire block foam is designed for around pipes and electrical wiring.

google "fire block foam code"

 

[Tuttles Revenge]

As long as your piping is adequately supported and the foam doesn't move it where it goes through the wall you should be fine. I've seen foam lift tubs full of water off the floor.

If its intended to keep rodents out, then I would embed a wire mesh or steel wool in with it. If its for fire rating, then use the appropriate orange stuff.