Roof Insulation Board R Value

Extruded polystyrene foam xps also known as blue board or pink board comes in many different thicknesses and edge profiles.

Roof insulation board r value.

Xps has an r value of 4 5 to 5 0 per inch of thickness. R value of various materials. Protector hd allows easy efficient scoring cutting and snapping which permits fast tight fabrication and all in a low dust environment. Commercial roof insulation recommendations zones 1 3 pima recommended r value r 20 zones 4 6 pima recommended r value r 25 zones 7 and 8 pima recommended r value r 30 all of alaska in zone 7 except for the following boroughs in zone 8.

R3 r18 r21 total roof r value. Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. The increase r21 r3 exactly 18 the value by which you are increasing the r value. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

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. High r value 2 5 r. You can even place it under the foundation slab. Calculate percent improvement in r value.

Understanding r value thursday december 13 2018 what does r value mean. Provides significantly more thermal insulation r value than wood fiber or gypsum boards. Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. This also means easy hoisting staging and maneuvering around the roof.

I calculate insulation resistance to heat loss or r percentage improvement always as relative to the original number. They keep your home at a comfortable temperature without the need to crank your heat. You should of course see the manufacturer provided technical data sheet for the r value of specific products. Rigid foam insulation also known as insulating boards provide high r values.

A higher r value means that the insulation will do a better job of holding in conditioned air whether that s heat in the winter or cool air in the summer. Rigid insulation is one of the best tools to reduce your energy costs. To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1.

Polyiso insulation thickness r value chart. Rsi r value système international is the metric equivalent. To convert rsi to r value multiply the rsi by 5 67826. R value is used in the united states.

For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3. With firestone you get one source with everything needed for any roof design.