Roof Insulation Rigid R Value

The higher the r value the greater the insulation performance.

Roof insulation rigid r value.

R3 r18 r21 total roof r value. When determining how much insulation you need don t guesstimate calculate. Rigid insulation is usually made up of fibrous materials or plastic foams. Know exactly how much you need with our project calculators.

All products in the acfoam polyiso roof insulation family are closed cell rigid foam insulation board flat or tapered. A rigid roof insulation board with high thermal efficiency johns manville r panel is compatible with multiple types of membrane systems. Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. R panel is manufactured with a closed cell polyisocyanurate foam core bonded to fiberglass reinforced facers and designed for use over metal nailable and non nailable roof decks with a variety of membrane systems.

Some products have reinforced facing to make them sturdier. Traditional loose fill insulation such as fiberglass or cellulose has an r value between r 2 0 and 3 5 per inch of thickness. Choose this option for areas that need a good amount of strength and water resistance. Rigid insulation r value by comparison usually ranges from r 4 0 to 6 5 and may get as high as r 8 7 depending on the insulation material.

It provides r values that range from 3 6 to 4 2 per inch. This material offers the highest r values about r 6 to 6 5. When it comes to insulation performance the difference is in the details. I calculate insulation resistance to heat loss or r percentage improvement always as relative to the original number.

The percentage increase increase increase original number 100. The increase r21 r3 exactly 18 the value by which you are increasing the r value. It provides about r 5 per inch.