The thickness of R38 batt insulation is usually about 12 inches. This substantial thickness helps to provide excellent thermal resistance, making it a popular choice for insulating attics and other areas where maintaining a high level of energy efficiency is crucial.
Insulation typically lasts 20 to 30 years, though some types, like fiberglass and rockwool, can last up to 50 years.
Spray foam insulation costs between $1,300 and $3,700 for a typical home, depending on the size and type of foam used.