Roof Insulation Rigid R Value

A rigid roof insulation board with high thermal efficiency johns manville r panel is compatible with multiple types of membrane systems.

Roof insulation rigid r value.

The percentage increase increase increase original number 100. R3 r18 r21 total roof r value. 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. I calculate insulation resistance to heat loss or r percentage improvement always as relative to the original number.

The increase r21 r3 exactly 18 the value by which you are increasing the r value. Some products have reinforced facing to make them sturdier. It provides about r 5 per inch. When it comes to insulation performance the difference is in the details.

With premium polyiso manufacturing atlas is able to produce the highest effective r values with minimal material thickness. Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. Traditional loose fill insulation such as fiberglass or cellulose has an r value between r 2 0 and 3 5 per inch of thickness. R value measures how well certain building insulation materials can resist heat.

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

It provides r values that range from 3 6 to 4 2 per inch. Jump to specific section. Choose this option for areas that need a good amount of strength and water resistance.