Blown In Insulation Walls R Value

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.

Blown in insulation walls r value. The higher the r value the better the thermal performance of the insulation. The common denominator among varieties of insulation is the r value. As a benchmark one inch of solid wood has an r value of 1. R value is a measure of insulation s ability to resist heat traveling through it.

In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and. Inside in the winter and outside in summer. The average cost of blown in insulation to achieve an r value of r 38 r 49 is 1 665 with most homeowners spending between 874 and 2 156 or 1 59 per square foot. After a few years blown in insulation tends to settle downward by a few inches which slightly reduces its overall thermal resistance known as r value because it leaves a small section at the.

This calculator is to be used as an estimating tool only. Mineral wool that is blown in also has an r value of 2 5 whereas mineral wool batts have an r value of 3. Input depth of existing blown in insulation in inches. Insulation level are specified by r value.

Fiberglass when installed loosely has an r value of 2 5. When installed as solid panels its r value can vary from 2 5 to 3 6 depending on the particular style. Recommended home insulation r values. Closed cell spf insulation r value 6 0 to 7 0.

Open cell spf insulation r value 3 5 to 3 8. The higher the r value per inch of thickness the better job the insulation will do when you heat or cool your home. The vast majority of production builders use batt insulation in the walls of the homes they construct but there s a strong case to be made for blown fiberglass. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

Perhaps it is obvious but the higher the r value the more resistance the material has to the transfer of heat that is keeping heat where you want it. The table below shows what levels of insulation are cost effective for different climates and. This is especially true for builders working under the 2015 energy code which requires that homes be evaluated according to resnet s home energy rating system hers. Note from this.

Blown insulation makes it much easier to earn a grade 1 hers. Fiberglass insulation r value 2 8 to 3 7. 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.