Attic Insulation Thickness R Value

For example residential icc code 5 2 9 r806 5 for attic insulation says air impermeable insulation is not required to meet the r value minimum listed in the chart above.

Attic insulation thickness r value. Insulation levels are specified by r value. You can achieve better thermal performance in your attic by adding an additional layer of insulation. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. You will need a higher r value of insulation if you live in the northeast than if you live in southern california.

There are many ways to retrofit a home with fiberglass and. As a benchmark one inch of solid wood has an r value of 1. Spray foam pink fiberglas vs. The r value of some insulations also depends on temperature aging and moisture accumulation.

Add the right kind of insulation. Insulation level are specified by 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. You can use the small pressurized cans of foam.

Recommended home insulation r values. In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7. The r value depends on the type of insulation its thickness and its density. The higher the r value the better the thermal performance of the insulation.

Meaning if you use a tight air seal you don t need to use as high of a total r value. When calculating the r value of a multilayered installation add the r values of the individual layers. Foam in place insulation can be blown into walls on attic surfaces or under floors to insulate and reduce air leakage. Some installations can yield a higher r value than traditional batt insulation for the same thickness and can fill even the smallest cavities creating an effective air barrier.

Here s another specific code example. Your home s age if your home is more than 10 year old you likely need more insulation. See the department of energy s doe ranges for recommended levels of insulation below. R value is a measure of insulation s ability to resist heat traveling through it.

The higher the r value the better the thermal performance of the insulation. Insulation project calculator how to install naima r value certification product training videos colab learning video library for pros distributor locator why owens corning insulation propink vs. Achieving greater r values in exterior walls. R value is a measure of insulation s ability to resist heat flow.

The table below shows what levels of insulation are cost effective for different climates and.