Roof Insulation R Value Code

There are many ways to retrofit a home with fiberglass and.

Roof insulation r value code.

These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. The document was updated in 2020 and is available on the carlisle syntec website. 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. Your home s age if your home is more than 10 year old you likely need more insulation.

State applicable code ashrae zone minimum r value state local al alabama 2015 alabama commercial energy code 2 r 25 3 r 25 state. While the r value for a material is typically given per inch the rsi is typically given per millimeter so please be aware that the r values and rsi values for the materials in the following table are not for equivalent thicknesses. Where you live different climates require different insulation r values. For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3.

Minimum r value non residential above roof deck 19727 57th avenue east puyallup wa 98387. Recommended home insulation r values. The higher the r value the better the thermal performance of the insulation. Energy codes and roofs.

R value based method of section c402 1 3 u c and f factor based method of section c402 1 4. You will need a higher r value of insulation if you live in the northeast than if you live in southern california. The table below shows what levels of insulation are cost effective for different climates and. Minimum insulation r value requirements non residential above roof deck.

Or component performance alternative of section c402 1 5 roof solar reflectance and thermal emittance fenestration in building envelope. If structural sheathing covers 40 or less of the exterior continuous insulation r value shall be permitted to be reduced by no more than r 3 in the locations where structural sheathing is used. Types of roof 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.

2015 code requires walls to be insulated with a minimum of r 20 or r 13 5 13 5 means r 13 cavity insulation plus r 5 insulated sheathing. Minimum insulation r value requirements non residential above roof deck is an extremely handy table for state and local jurisdictions in the united states. Specific insulation requirements of section c402 2 thermal requirements of either. 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.

Insulation level are specified by r value.