Residential Roof R Value Requirements

R value is a measure of insulation s ability to resist heat traveling through it.

Residential roof r value requirements.

Minimum insulation r value requirements by state. 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. Iecc 2015 requirements by climate zone 3.

Where section 1102 1 2 requires insulation r values greater than r 30 in the ceiling and the design of the roof ceiling assembly does not allow sufficient space for the required insulation the minimum required insulation r value for such roof ceiling assemblies shall be r 30. Always double check with your local authority to confirm which code is currently in effect. The higher the r value the better the thermal performance of the insulation. 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.

When determining how much insulation you need don t guesstimate calculate. R value based method of section c402 1 3 u c and f factor based method of section c402 1 4. 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. Minimum insulation r value requirements non residential above roof deck.

The document was updated in 2020 and is available on the carlisle syntec website. Insulation level are specified by r value. Minimum insulation r value requirements non residential above roof deck. Browse product options or contact your local insulfoam rep to help you quickly pick the best products to simplify your building envelope needs and fit your project budget all with one supplier.

R value measures how well certain building insulation materials can resist heat. The higher the r value the greater the insulation performance. Minimum insulation r value requirements non residential above roof deck is an extremely handy table for state and local jurisdictions in the united states. State applicable energy ashrae zone minimum r value state local ms mississippi ashrae 90 1 2010 2 r 20 3 r 20.

Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities. R value state local al alabama 2015 alabama commercial energy code 2 r 25 3 r 25 state local ak alaska 2012 alaska building energy efficiency standard. 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. What r value do i need.