Bchbound wrote:
Be careful not to overfill it. That stuff can have very strong expanding
properties. I once put it around a window and when it expanded the window
would not slide. I have recently seen products at home depot that expand
to a smaller volume which would have less chance of cracking something.

Good to point that out, but it doesn't happen for the reason stated,
although that is the common perception. The insulating foam you're
referring to will only expand to fill voids, and if there are any holes
or cracks, it will find its way out of there too. It will not expand
adding pressure. The problem in the application you're referring to is
that the foam fills the cavity and removes the expansion and contraction
characteristics. i.e. when everything is expanding in warmer/hotter
weather, your window/frame can no longer do this. Best case you won't
be able to open your window. Worst case, something breaks.

-Jim