Residential Metal Building Roof R Value

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials.

Residential metal building roof r value.

Based on astm c518 calculation method the door has an r value of up to 11 but using astm c1363 tested operable the same door only have an r value of up to 3 5. For a very good introductory overview article on r value see r values over at the website of. To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. An optional purlin bearing leg pbr rests on purlins and provides support for fastening the panel lap.

R value of building materials material r inch r thick ness fiberglass inch 3 00 1 inch 4 00. In the chart above you will notice that there are two vastly different r values provided for insulated metal doors with polyurethane insulation. R value is defined as an insulating material s capacity to resist the flow of heat. Metal 1 00 metal insulating 2 inch w urethane 15 00 air films interior ceiling 0 61.

To convert rsi to r value multiply the rsi by 5 67826. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1 93721. Roofing materials asphalt shingles 0 44 wood shingles 0 97 windows single glass 0 91. You should of course see the manufacturer provided technical data sheet for the r value of specific products.

R panel is manufactured with a closed cell polyisocyanurate foam core bonded to fiberglass reinforced facers and designed for use over metal nailable and non nailable roof decks with a variety of membrane systems. Higher r values are an indication of greater insulation power. R panel is also a popular choice for residential metal roofing especially in the southwest. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities.

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. Additionally you ll recoup an average of 85 9 percent of. R value of various materials. 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 panel is a multi use wall and roof panel used primarily in pre engineered metal building applications. Minimum insulation r value requirements by state. In insulated metal panels r value of the core foam is calculated according to the astm c518 standard test method.