In the event that cavities are overfilled, excess insulation needs to be trimmed off due to its great expansion rate. A hand saw or Sawz – All blade can be used for scarfing the excess material. Polyicynene is not biodegradable, but the insulation waste can be used in the attic as loose-fill insulation. Working with Icynene, although not difficult, is a little laborious when it is necessary to run additional plumbing or electrical cabling through cavities after application of the foam.