Exterior Wall Insulation R Value

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.

Exterior wall insulation r value.

For instance if you have a material with an r value of 12 attached to another material with an r value of 3 then both materials combined have an r value of 15. The net effect on the r value of the wall with the studs transferring heat cold thru conductive properties is the actual rating of that. 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. 1 2 exterior plywood has an r value of 0 63 and exterior wood bevel siding has an r value of just 0 80.

In simple terms r values measure the effectiveness of insulation and a higher number represents more effective insulation. Thickness density and type of materials are some factors that contribute to. The r refers to absolute thermal resistance. Insulation level are specified by r value.

Find your zone on the map and then use the above insulation r value chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces. The higher the r value the better the thermal performance of the insulation. R value is a measure of insulation s ability to resist heat traveling through it. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

Let me explain when the general public hears an r 13 wall insulation they believe that in fact they have an r 13 insulation value in their exterior walls. The truth is this studs have an r value of 3 5. The table below shows what levels of insulation are cost effective for different climates and. Other typical wall materials have similarly low values.

Higher r value numbers mean that the insulating material resists the cold or heat from the outside better. Recommended home insulation r values.