If the insulation is rock wool, you can estimate that 4 inches is around R-11, 6 to 7 inches is R-19, 9 inches is R-26 and 10 or 11 inches is R-30.Nov 7, 2008
What size is R-11 insulation?
Brand Johns Manville
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Product type Batt
Product width 16", 24"
Product thickness 3.625"
R value R11
What is the standard thickness of insulation?
Measure the depth of your current insulation. R-38 is the industry standard, and the minimum thickness for R-38 is 12 inches. If your current insulation is only 5 inches deep, you'll need to add 7 inches of insulation to achieve the 12-inch R-38 rating. Measure the area needing insulation.
What size is R 11 insulation?
Brand Johns Manville
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Product type Batt
Product width 16", 24"
Product thickness 3.625"
R value R11