Residential Roof Insulation R Value

Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency.

Residential roof insulation r value. You will need a higher r value of insulation if you live in the northeast than if you live in southern california. R value is a measure of insulation s ability to resist heat traveling through it. Recommended home insulation r values. 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.

Know exactly how much you need with our project calculators. R value measures how well certain building insulation materials can resist heat. Minimum insulation r value requirements by state. There are many ways to retrofit a home with fiberglass and.

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. The table below shows what levels of insulation are cost effective for different climates and. When determining how much insulation you need don t guesstimate calculate. The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.

Where you live different climates require different insulation r values. These products provide a high r value inch excellent sound attenuation characteristics and outstanding fire performance. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process. State applicable energy ashrae zone minimum r value state local ms mississippi ashrae 90 1 2010 2 r 20 3 r 20 state local mo missouri 2012 iecc 4 r 25 5 r 25 state only mt montana 2012 iecc 6 r 30.

Insulation level are specified by r value. The document was updated in 2020 and is available on the carlisle syntec website. 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. Your home s age if your home is more than 10 year old you likely need more insulation.

The higher the r value the greater the insulation performance. Minimum insulation r value requirements non residential above roof deck. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities.