Thermal Bridging Calculator

Calculate effective wall R-value accounting for thermal bridging through framing members using parallel path method.

R-value between framing members
h·ft²·°F/Btu
Include wood/steel framing, sheathing, air films
h·ft²·°F/Btu
Wood 2x4 16" OC: ~0.15, 2x6 24" OC: ~0.12, Steel: ~0.15-0.25

Results

Cavity Fraction-
Effective Wall R-Value-h·ft²·°F/Btu
R-Value Reduction-%
References: ASHRAE Fundamentals Ch. 27, ASHRAE 90.1 Appendix A - Rated R-Value Method