R Value Of Roofing Materials

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

R value of roofing materials.

Rsi r value système international is the metric equivalent. For instance if you have a material with an r value of 12 attached to another material with an r value of 3 then both materials combined have an r value of 15. Some of the possible material combinations may not be suitable for actual constructions i e. The following table is in metric form.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. Eps based claddings directly fixed on timber framing. Ft sbs self adhering cap sheet roll for low slope roofing in hickory. Additional r value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included such as 1 solid foam polyisocyanurate r 8 extruded polystyrene r 5 expanded polystyrene r 4 or 1 of perlite r 2 7 and for an exterior air film winter no wind r 0 17 an interior.

To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. The average r value for some common roof materials include. Material r inch r thick ness insulation materials fiberglass batt 3 14. What are common r values.

R value of building materials material r inch r thick ness fiberglass inch 3 00 1 inch 4 00. This webpage calculates the r value of walls roofs and suspended floors for most insulation material r values. There are many websites on the internet which have imperial building material r value numbers but not so many with metric r value numbers. Click here to go to our calculator to understand the real r value of a ceiling system or wall system with gaps in the insulation.

Torch down roofing peel and stick roofing asphalt roll roofing low slope roll roofing roll roofing mineral surface rolled roofing roll roofing roofing materials related products liberty 3 ft. To calculate the r value of a roof system your contractor will take into account the underlayment coverboards adhesives insulation and even the membrane. To convert rsi to r value multiply the rsi by 5 67826. As we said before the r value measures the thermal resistance of a material.

These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. Roofing materials asphalt shingles 0 44 wood shingles 0 97 windows single glass 0 91. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1 93721. R value of various materials.

It uses the iso thermal planes method the same method as used in nzs4214 2006.