R Value Of Rigid Insulation Roof

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.

R value of rigid insulation roof.

Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. 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. To convert rsi to r value multiply the rsi by 5 67826.

Conditioned per atsm c1289 test method astm c5181 2. The higher the r value the greater the insulation performance. Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. For a very good introductory overview article on r value see r values over at the website of.

When determining how much insulation you need don t guesstimate calculate. Rsi r value système international is the metric equivalent. R value is used in the united states. Thickness inches r value in i p imperial rsi r value in metric 0 5.

Traditional loose fill insulation such as fiberglass or cellulose has an r value between r 2 0 and 3 5 per inch of thickness. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1. A rigid roof insulation board with high thermal efficiency johns manville r panel is compatible with multiple types of membrane systems. R value of various materials.

Rigid insulation is usually made up of fibrous materials or plastic foams. You should of course see the manufacturer provided technical data sheet for the r value of specific products.