Green Roof Assembly R Value

In an uninsulated house more heat is lost through the ceiling and roof than any other part of the house making the roof the top priority for insulation.

Green roof assembly r value.

Plants need water to grow so the green roof is designed to retain some degree of moisture. You should of course see the manufacturer provided technical data sheet for the r value of specific products. Replacing the impervious surface of a conventional roof with. What r value do i need.

Every construction design architect engineer a e knows a material s r value is an important factor when specifying insulation products with many regulations requiring minimum values for wall ceiling and roof assemblies. Insulation thermal resistant r value requirements for the building should be integral to the roof membrane assembly below the vegetated roof components. For a very good introductory overview article on r value see r values over at the website of. Vegetated roof components and growing medium should not be relied upon for effective or consistent thermal resistance heat gain heat loss.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. Garden roof assembly hydrotech s garden roof assemblies combine the proven performance of our monolithic membrane 6125 roofing waterproofing with proven green technology. Depending on where you live and the part of your home you re insulating walls crawlspace attic etc you ll need a different r value. R value of various materials.

Sprayed polyurethane foam spf will have an r value of 7 14 when it is newly installed. As we said before the r value measures the thermal resistance of a material. Pitched timber framed roof r 3 3. The amount shown is an average amount used for roof system r value calculations.

You can find some of the examples here. Typical recommendations for exterior walls are r 13 to r 23 while r 30 r 38 and r 49 are common for ceilings and attic spaces. R value is essentially a product s resistance to heat flow which means that the higher the product s r value the better it is at insulating the home and improving energy efficiency. Knowing what r value and u values mean is key to following energy codes and to selecting products that best suit the climate zone you are building in.

Extruded expanded polystyrene insulation is commonly used in inverted roof membrane assemblies irma. The branz house insulation guide provides construction r values for common construction types. Determining insulation r value accuracy. Unlike conventional earth covered structures garden roof assemblies are lightweight and can be installed on a wide variety of new and existing structures.

However a green roof does not provide additional insulation.