Grading Continuous Insulation

You can use the spreadsheet calculator attached to determine effective R value for continuous insulation that is not Grade I. However, please be cautious about using insulation grading for spray foam insulation, because most applications would not have gaps all the way through the material, they would just have low spots and high spots. You may be better off using the maximum observed depth which can be described as grade 1 per Insulation Grading instructions in the RESNET Standard.