Can IKO Enertherm cavity wall PIR insulation be used as full fill insulation with no residual cavity in masonry external wall Yes, IKO enertherm cavity wall PIR insulation can be used in masonry external walls, however there should always be a 50mm residual cavity, never full fill. I wish to create a cool room. How would the properties of 75mm IKO Enertherm compare with those of 75 Celotex? What are the disposal instructions for the hotmelt PermaTEC Anti-Root system? I am compiling an O&M and require this information.