How many inches is r11 insulation?
If your attic has fiberglass material, 5 inches gives about an R-11 insulation level, 8 to 9 inches around R-19, 12 inches R-26 and 13 to 14 inches is around R-30.Click to see full answer. Correspondingly, how thick is r11 insulation? Fiberglass Batt Insulation Characteristics Thickness (inches) R-Value Cost (cents/sq. ft.) 3 1/2 11 12-16