Roof Membrane R Value

Pattern with perimeter sheets attached 6 o c.

Roof membrane r value.

Both types have an r value ranging from 4 r to 6 r per 1 inch of insulation thickness. 1 000 sq ft 500 sq ft. A recent study of everguard tpo roofs installed between 8 and 16 years ago found they all performed above astm standards for newly manufactured tpo. What are common r values.

For a very good introductory overview article on r value see r values over at the website of. Gaf analyzed membrane samples from roofs across the us and studied thickness over scrim surface cracking and the ability to repair aging tpo membranes. Always check with your local code authority. R value is calculated by more than just the insulation.

The tables show a u value r value and c value for several thicknesses of siplast roof insulation systems. Duro last 50 mil membrane is manufactured with 28 mil of thickness on the top performance layer far exceeding industry standards as well as competitor systems with equal and even greater mil values. Single ply roofing information. The amount shown is an average amount used for roof system r value calculations.

A u value incorporates the total system approach to insulation design. You should of course see the manufacturer provided technical data sheet for the r value of specific products. Extruded expanded polystyrene insulation is commonly used in inverted roof membrane assemblies irma. 5 x 100 128 lbs.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. P roduct sizes dim ensions and w idths are nom inal values and are subject to norm al m anufacturing packaging tolerance and variation c olors f u ll r oll s ize f u ll r oll w eigh t h alf r oll s ize h alf r oll w eigh t w hite t an g ray 10 x 100 256 lbs. Please note that the r values for roof membranes shingles tiles air films and roof deck materials might or might not be permitted by your local code to be included when total roof assembly r value is being calculated for the purpose of satisfying energy code requirements. For white and black membranes the table outlines the necessary adjustments in r values to maintain a roof assembly s energy performance.

The average r value for some common roof materials include. The u value includes the thermal resistance values for roofing and both inside and outside air films in addition to the insulation material. Sprayed polyurethane foam spf will have an r value of 7 14 when it is newly installed. R value of various materials.

Mechanically attached installation uses heavy duty screws and barbed plates to hold the membrane down tightly and is not affected by possible iso de lamination. To calculate the r value of a roof system your contractor will take into account the underlayment coverboards adhesives insulation and even the membrane. Quite the contrary in colder regions ashrae zones 4 through 8. The membrane is attached using 12 o c.