SF40 is Superfoils extra performance multifoil insulation. Extremely cost effective with a 68% increase in performance over our standard multifoil. SF40 beats any multifoil competitor products R value.With a mission to build a better multi foil insulation SF40 combines the technical innovation of 37 layers and is configured for maximum efficiency, achieving higher values than previously thought possible within the industry. The enhanced thickness combined with radiant reflective properties and air barrier properties provide benefits over traditional (non reflective) open face insulation like glass fibre. SF40 includes CE certified vapor and water barrier outer layers.SuperFOIL SF40 maximises roof and wall insulation with efficient use of space. SuperFOIL also has the strongest multi foil material aiding installation and reducing waste. LABC registered detail makes Building Regulations simple. Please note we would recommend using 30mm staples with the SF40. Properties Length: 10m.Width: 1.5m.Roll size: 15m2.Thickness installed: 65mm.Weight per roll: 18.5kg.Thermal Resistance - rValues:For pitched roofs: 3.58 m2K/W.For walls: 4.04 m2K/W.For flat roofs: 3.58 m2K/W.For floors: 5.69 m2K/W.Layers:Polypropylene reinforced heavy outer laminated foil: 2x layers.Aluminium coated reflective foil PET layers: 12x layers.Thermal foam separation layers: 16x layers.Loft quilt: 6x layers.Total layers: 37x layers. Application Air seal & radiant barrier.Building regs compliant.Horizontal or vertical fitting.25mm air gap required.Cut with knife or scissors.