TB4000 is targeted at cut-to-fit applications between rafters or joists and enables users to achieve lower U-values with a single layer of insulation than has previously been possible. It is also appropriate for use in floors and walls. With low emissivity foil facings, TB4030 is manufactured from rigid polyisocyanurate (PIR) using a blend of blowing agents that have zero ozone depletion potential (zero ODP) and low global warming potential (GWP).