On both single and double layer blanket insulation installations, the facing runs parallel to and overlaps the purlins or joists creating a vapor retarder. On single layer installations, unfaced ELAMINATOR® insulation is rolled out over and perpendicular to the purlins. For double layer applications (Fc – Filled Cavity), a layer of ELAMINATOR® insulation is placed in the purlin cavity and the second layer is rolled out over and perpendicular to the purlins. ELAMINATOR® 300 Series machines offer leading edge fall protection for any size project with slopes 3:12 or lower.