r19 rigid roof insulation thicknessrigid insulation board thicknessrigid foam insulation thicknessr30 rigid insulation thicknessr13 rigid insulation thicknessr20 rigid insulation thicknessr19 rigid insulation thicknessr38 rigid insulation thicknessthick foam insulationr5 rigid insulation thicknessfoam board insulation thicknessr30 blown insulation
