Typical Wall Insulation R Value

The higher the r value the better the thermal performance of the insulation.

Typical wall insulation r value.

All of us would love to have r 25 values on our rvs but the technology isn t there yet. 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 r 0 87 value for the first value in this air r value table subsection. See the department of energy s doe ranges for recommended levels of insulation below.

Recommended home 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. The table below shows what levels of insulation are cost effective for different climates and. Insulation level are specified by r value.

The r value of air is r 1 while a thick layer of densely packed fiberglass can have an r value of r 25. Air gap or air film 3 4 air space insulating properties. Does not consider internal convection effects. 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.

Since the wood framing members have a thermal resistance r value roughly equal to only one quarter the r value of typical insulation products the overall r value of the wall is calculated at. Most rv manufacturers use a dense polyfoam block foam insulation that ranges between r 5 to r 7 in their rv sidewalls.