R Value Of Concrete Wall Below Grade

The higher the r value the better the thermal performance of the insulation.

R value of concrete wall below grade.

Concrete block wall with perlite in cavities r 2 9. By doubling the thickness of the wall to 16 inches the r value only increases by 0 50. In addition to r value stability rigid foam insulations differ in their rates of moisture absorption and their ability to dry. Concrete block wall with air in cavities r 2 0.

Call pca at 847 966 6200 ext. R value is a measure of insulation s ability to resist heat traveling through it. 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. In addition the doe recommends r 10 to r 20 insulation for under a slab which we have not taken into consideration for this article.

By comparison most xps warranties typically cover only up to 90 percent of the published r value to account for the r value degradation that occurs in the field. The r value listed by pca for a normal weight 144 pcf 6 inch concrete wall is 1 23 and includes inside and outside air film resistances which contribute to overall thermal resistance. For example if you have a type of insulation. Above grade concrete wall including inside and outside air films r 1 2 for 6 inch r1 4 for 8 inch.

564 to obtain copies of this reference. The r value of an uninsulated 8 inch thick basement wall built using normal weight concrete is 1 35 based on data from the 1993 american society of heating refrigeration and air conditioning engineers handbook. The table below shows what levels of insulation are cost effective for different climates and locations in the home. The minimum insulation r value recommended by the department of energy for horizontal below grade surfaces in cold climates is r 10 to r 15.

R 0 125 per inch for soil sounds pretty reasonable if we assume about 20 moisture content and if we consider for comparison or a sanity check that the r value of uninsulated concrete is about r 0 8 inch. Concrete and block walls. Ensure minimal long term moisture absorption.