Roof Insulation R Value

The table below shows what levels of insulation are cost effective for different climates and locations in the home.

Roof insulation r value.

The higher the r value the better the thermal performance of the insulation. R value measures how well certain building insulation materials can resist heat. Insulation level are specified by r value. Steep slope or pitched roofs will almost never include insulation as a part of the roof assembly.

Polyiso is the industry s premier roofing insulation. 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. To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. Carlisle s tapered insulation helps promote rooftop drainage while providing excellent insulating value.

Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. See the department of energy s doe ranges for recommended levels of insulation below. The increase r21 r3 exactly 18 the value by which you are increasing the r value. R value is a measure of insulation s ability to resist heat traveling through it.

The r value you have to achieve will be a big part of figuring out the type and thickness of the insulation you will install. When determining how much insulation you need don t guesstimate calculate. You will need a higher r value of insulation if you live in the northeast than if you live in southern california. At firestone building products we offer more than just roofing and building solutions.

The higher the r value the greater the insulation performance. I calculate insulation resistance to heat loss or r percentage improvement always as relative to the original number. It can be attached using a variety of methods and is compatible with all of carlisle s single ply systems. The amount of insulation recommended for your home will vary depending on a number of factors.

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. We offer a partnership and complete solution that lasts long after your project is finished. R3 r18 r21 total roof r value. Insulation in this case will be below the roof deck or considered part of the ceiling assembly.

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. Know exactly how much you need with our project calculators. 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.

Where you live different climates require different insulation r values.