intumescent caulk or expanding foam
Before I close up my walls, I wanted to seal up the bottom and top plate penetrations. Which is more appropriate? Intumescent caulk/putty or expanding foam. The penetrations have either copper water piper, ABS drain/vent pipe, or Romex wiring.
My worry is any possible reactions between the caulk or foam with the different materials - copper, ABS and wire sheathing.
I've heard that expanding foam, in a fire, will fuel the flame faster and disintegrate while intumescent is obviously a fire stop.
I guess another way to ask the question is whether top and bottom plates should be sealed for air penetration or act as fire stops as well?
Thanks for any insight.