Roof System R Values

The average r value for some common roof materials include.

Roof system r values.

R value because many states or regions require that a roof system have a minimum amount of thermal resistance on commercial industrial and or institutional buildings. The higher the r value the better a material performs as a thermal insulator. Rsi r value système international is the metric equivalent. The higher the r value the more the material insulates.

3 85 per inch polyiso. It uses the iso thermal planes method the same method as used in nzs4214 2006. 0 33 per inch of thickness bur gravel. 6 6 per inch xps insulation.

To convert rsi to r value multiply the rsi by 5 67826. 5 0 per inch eps insulation. 6 6 per inch of thickness metal. 0 34 per inch of thickness bur smooth.

R value table for roofing materials and building insulation. Types of roof insulation. Here are the r values of the most popular commercial roofing systems. Some of the possible material combinations may not be suitable for actual constructions i e.

Eps based claddings directly fixed on timber framing. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1 93721. R value is used as a measurement of the effectiveness of thermal insulating materials. The way it works is simple.

0 24 per inch of thickness epdm. 0 00 per inch of thickness tpo.