Residential Roof R Value Requirements

Minimum insulation r value requirements non residential above roof deck.

Residential roof r value requirements.

Minimum insulation r value requirements by state. 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. 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. Minimum insulation r value requirements non residential above roof deck.

Specific insulation requirements of section c402 2 thermal requirements of either. Below is a table outlining the basic r value requirements for walls roofs and floors. R value is a measure of insulation s ability to resist heat traveling through it. Non residential above roof deck this matrix provides the minimum insulation r values required by local and state municipalities.

To meet r 38 in a roof or ceiling you would need about 6 or 6 5 inches of closed cell spray foam. Or component performance alternative of section c402 1 5 roof solar reflectance and thermal emittance fenestration in building envelope. Quick roofing guide to the international building code. The document was updated in 2020 and is available on the carlisle syntec website.

Iecc 2015 requirements by climate zone 3. Closed cell spray foam has an r value of about r 6 or r 6 5 per inch. Recommended home insulation r values. Insulation level are specified by r value.

Minimum insulation r value requirements non residential above roof deck is an extremely handy table for state and local jurisdictions in the united states. Quick roofing guide to the international residential code. 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. The higher the r value the better the thermal performance of the insulation.

Roofing contractor license verification by state. Floors over unheated spaces need to be insulated to a minimum of r 19 in zones 3 and 4. R value based method of section c402 1 3 u c and f factor based method of section c402 1 4. There are two model building codes which form the basis of almost all of the building codes in the united states.

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. Required r values for walls roofs and floors.