Blown Attic Insulation R Value Per Inch

While there are additional considerations such as venting and moisture problems to take into account when you insulate under floors the united states department of energy recommends an r 25 rating in cold climates and an r 11 in warmer parts of the country.

Blown attic insulation r value per inch.

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. The r value per inch for different types of insulation varies depending on the. Foam in place insulation can be blown into walls on attic surfaces or under floors to insulate and reduce air leakage. The r value of insulation is a measure of how well it reduces the flow of heat and cold into and out of your house.

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. Input depth of existing blown in insulation in inches. This calculator is to be used as an estimating tool only. You can use the small pressurized cans of foam.

Click the button to calculate the approximate r value for this job. By today s standards most homes built more than 10 years ago can be considered under insulated. The higher the r value per inch of thickness the better job the insulation will do when you heat or cool your home. As a benchmark one inch of solid wood has an r value of 1.

How much is enough. Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system.