To get the most R-value with the least thickness, use batt insulation with higher R-value per inch in combination with rigid foam insulation. Rigid foam sheeting has an R-value ranging from R-5 to ...

Typical R-value: R-3 to R-4 per inch of thickness ... and address any large drainage issues. If using insulation other than XPS rigid foam or spray foam, consider adding some sort of vapor ...

Spray foam insulation in Bellingham WA has been hailed as the best solution for people interested in energy savings comfort and sustainability Spray foam recognized as the highest R-value material in ...