If a material has an R-value of 3.6 per inch, what is the R-value for a thickness of 3.5 inches?

To determine the R-value for a thickness of 3.5 inches, you would multiply the R-value per inch (3.6) by the number of inches (3.5). The calculation proceeds as follows:

R-value = R-value per inch × thickness in inches

R-value = 3.6 × 3.5

When you perform this multiplication:

3.6 times 3.5 equals 12.6.

Thus, the R-value for a material that is 3.5 inches thick, given that its R-value is 3.6 per inch, is 12.6. This understanding of how to calculate R-values based on thickness and the R-value per inch is critical in assessing insulation effectiveness in building components.