8¼ ” thick, R-30C EcoTouch® Thermal Batt insulation prevents moisture damage and helps assure long roof life by providing 1″ of ventilation air space between the insulation and roof deck.Click to see full answer. Just so, how many inches of insulation is r30?In temperate coastal areas such as Zone 3, attic insulation of at least R30 up to a maximum of R60 is recommended. For loose-fill cellulose, this translates to a total depth ranging from 8 inches up to 16 inches.Also Know, what is R 19 insulation thickness? When you compress fiber glass batt insulation, the R-value per inch goes up, but the overall R-value goes down because you have less inches or thickness of insulation. The standard R-19 fiberglass batt is 6.25″ thick. Similarly, you may ask, how thick is r30 insulation? Compare all Specifications Insulation Location Attic,Ceiling,Floor Insulation Location 2×4 Wall Roll or Batt Roll or Batt Product Length (ft.) 4 ft Product Length (ft.) 7.75 ft Faced or Unfaced Faced Faced or Unfaced Faced Product Thickness (in.) 9.5 in Product Thickness (in.) 3.5 in What does R 30 insulation mean?A wall is R-19, a roof is R-30 — what does this mean? Essentially R-value is a measure of thermal resistance, or the ability to prevent the transfer of heat. The larger the number, the harder that insulation is working at preventing heat conduction. The less heat loss, the lower your energy bills.