Rigid Roof Insulation R Value Per Inch

Jm revised lttr values.

Rigid roof insulation r value per inch.

Jm suggests that design professionals use 5 7 r inch as a design specification for its foam products. Estimated r value of asbestos insulation per inch for pipe insulation corrugated paper. Polyisocyanurate also known as polyiso is seen in all kinds of commercial building applications and more recently with residential building projects. R value per inch ft f hr btu rsi per millimeter k m w r value for typical installed thickness not per inch source.

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. Asbestos lagging and paste will have a lower value. The reflective foil facing makes it an excellent insulation board when radiant heat is involved. Membrane systems vary in color and chemical composition and may be mechanically attached loose laid ballasted or fully adhered.

R value of roofing materials and building insulation. Rigid insulation is usually made up of fibrous materials or plastic foams. Traditional loose fill insulation such as fiberglass or cellulose has an r value between r 2 0 and 3 5 per inch of thickness. Asbestos cement board r value.

Some products have reinforced facing to make them sturdier. The same insulation will hold more heat the thicker it is installed. Choose this option for areas that need a good amount of strength and water resistance. Asbestos cement shingle siding.

Asbestos loose packed fibers powder. Eight inches of poor quality insulation may have a higher and better r value than one inch of top quality insulation. For a 1 in thick 4 8 panel comes unfaced or with a number of different plastic facings. Polyiso is typically used with a foil facing and it has an r value of 7 0 to 8 0 per inch of thickness.

Note from this chart that the ideal r value differs for each part of your home. Asbestos corrugated paper pipe insulation. Resistance to water absorption and a stable long term r value of 5 per inch is an excellent insulation layer for use below single ply membrane roofi ng systems. 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.

So you need to know an insulation product s thickness as well as its r value in order to compare it to another product. Also called styrofoam insulation this is the least expensive material. It provides r values that range from 3 6 to 4 2 per inch. Thermal conductivity k 0 15.

Built up roof membrane gravel surfaced membrane and gravel only 0 33. Falls in the middle of the three types of rigid foam insulation in both cost and r value used most in walls or below grade applications recyclable and at about r 5 per inch costs around 42 per sq. Jm is proud to be a pima member and have its product third party certified under the pima quality mark program.