What is the R-value of XPS per inch?

The R-value of extruded polystyrene (XPS) insulation is approximately R-5 per inch. This R-value indicates the thermal resistance of the material, meaning it effectively reduces heat transfer, providing good insulation for buildings. Materials with higher R-values indicate better insulating properties.

XPS is known for its closed-cell structure, which not only contributes to its thermal performance but also provides moisture resistance. This characteristic makes it suitable for various applications, including below-grade insulation and areas prone to exposure to moisture.

In terms of comparison, materials with lower R-values would not provide the same level of thermal resistance per inch, making XPS a more effective choice for energy efficiency in building insulation.