A referendum to place the duties of the Recorderâs Office into the County Clerkâs Office was passed by the voters of McLean County on November 6, 2012 and took effect December 31, 2013.
Depending on where you live, itâs recommended that attics have a minimum R-value of R-30 in warm climates to R-60 in cold climates. Recommended Insulation by Climate. By dividing the recommended R-value for your area by the R-value of your particular type of insulation, you find that an attic should have on average: Warm Climates (R-30 to R-49): 1  Fiberglass (blown): 14â â 18â. 2  Fiberglass (batts): 11â â 14â. 3  Cellulose (blown): 11â â 13â. 4  Rock Wool (loose): 12â â 18â. 5  Foam (sprayed): 5â â 11â.
Our free calculator uses recent, trusted data to estimate costs for your Attic Insulation project. For a basic 500 square feet project in zip code 47474, the benchmark cost to Insulate an Attic ranges between $1.67 - $3.18 per square foot* .