Rubber Roof Membrane R Value

You should of course see the manufacturer provided technical data sheet for the r value of specific products.

Rubber roof membrane r value.

The average r value is r 5. Both types have an r value ranging from 4 r to 6 r per 1 inch of insulation thickness. It is top quality and the most cost effective product for your flat roof. 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.

The amount shown is an average amount used for roof system r value calculations. 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. Quite the contrary in colder regions ashrae zones 4 through 8. We recommend having at least 20 r value worth of material for optimal energy efficiency.

Sprayed polyurethane foam spf will have an r value of 7 14 when it is newly installed. You can expect to pay about 55 100 sq ft. R value of various materials. Pattern with perimeter sheets attached 6 o c.

For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1 93721. The average cost of extruded polystyrene insulation is 0 42 sq ft. The membrane is attached using 12 o c. For white and black membranes the table outlines the necessary adjustments in r values to maintain a roof assembly s energy performance.

For a very good introductory overview article on r value see r values over at the website of. Expanded polystyrene eps with the highest r value per dollar eps is used for roof wall and floor insulation. Smooth tpo fleece back tpo self adhered tpo tpo colors extreme tpo. After it ages a few months the r value will reduce to somewhere.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. For a 1 in thick panel. While expensive the best insulation is polyiso rigid foam. Xps is semipermeable with a perm rating of 1.

To convert rsi to r value multiply the rsi by 5 67826. Eps can be used for ground contact and does not retain water over time. For example while optimum performance using a black membrane the assembly must utilize insulation with an r value of 29.