What is the cost to insulate between the ceiling joists of a 20` x 30` ceiling with packed 4″ thick loose insulating wool. One bag fills 4 c.f. based on a density of 10 lbs. per c.f. One bag of wool costs $1.69 plus 6% sales tax.

What is the cost to insulate between the ceiling joists of a 20` x 30` ceiling with packed 4″ thick loose insulating wool. One bag fills 4 c.f. based on a density of 10 lbs. per c.f. One bag of wool costs $1.69 plus 6% sales tax.