Hi, I'm in the middle of home renos and I would like some opinions on: What is the best tool to cut through rigid foam? Someone suggested a lee valley pruning saw, but there are several and I'm not sure which one. What about a heat knife? Also, what sorts of glues/adhesives are compatible with foam? Is PL300 the way to go? What about expanding foam adhesives? I don't want to just use the little spray cans. What sorts of pistol grip dispenser systems are there? Help please. Thanks

A circular saw with an abrasive blade for metal or masonry cutting will make a clean cut in ICF foam with little or no mess. The foam melts as the blade goes through it and you don't get those little beads of EPS everywhere.

Titebond II Premium wood glue also works well for gluing foam, but it won't bridge large gaps like the expanding foam adhesives (Enerfoam, Great Stuff Pro, etc).

Good, non-rented bracing, like PanelCraft or Giraffe.
Table saw
hand saw
Rasp
Hilti foam gun, worth the extra cost
Great stuff or foam to foam
Impact screw guns and lots of screws

Not to hijack this thread but I have a question on the hilti gun:

How do you clean it?

I have one that is clogged. Ball bearing moves and drains the can but never makes it through the gun. Can this gun be disassembled for cleaning?

I have never had to clean a Hilti gun, they just work. You did try to get the cleaner through it? Try soaking it in acetone.