Attic Insulation R Value Chart

R value is a measure of insulation s ability to resist heat traveling through it.

Attic insulation r value chart.

How much insulation should you install. The greater the r value the greater the insulating performance. Installing more insulation in your home increases the r value and the resistance to heat flow. As a benchmark one inch of solid wood has an r value of 1.

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 your attic to reach r 30 if you live in zones 2 or 3. The r value depends on the type of insulation density and thickness. The table below shows what levels of insulation are cost effective for different climates and. How well insulation resists heat flow depends on how and where you install the insulation.

When calculating the r value of a multilayered installation add the r values of the individual layers. Chart courtesy of energy star. R value refers to the insulation s ability to resist heat flow. The r value of some insulations also depends on temperature aging and moisture accumulation.

The higher the r value the better the thermal performance of the insulation. Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system. 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. Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.

Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation. 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. A high r value then means higher effectiveness. Insulation level are specified by r value.

Colder climates will typically require a higher r value for even greater thermal. Note from this chart that the ideal r value differs for each part of your home. The amount of insulation recommended for your home will vary depending on a number of factors. R value requirements are different based on your location.

How do you figure out r value. For some types of insulation the r value also depends on aging temperature and moisture. You will need a higher r value of insulation if you live in the northeast than if you live in southern. Recommended home insulation r values.