U-Value Calculator
Calculate thermal transmittance for wall, roof, and floor assemblies. Add material layers, configure surface resistances, and get U-value results with bridging corrections and R-value conversions.
ISO 6946 · BR 443 · ASHRAE 90.1
Assembly Settings
Material Layers
Total: 100 mmLayer 1
Results
U-Value
0.357 W/m²K
R-Value (metric)
2.802 m²K/W
R-Value (imperial)
15.91 ft²·F·h/BTU
Total Thickness
100 mm
Layer Breakdown
| # | Layer | Thickness (mm) | R (m²K/W) | Bridged R |
|---|---|---|---|---|
| - | Internal Surface (Rsi) | - | 0.130 | - |
| 1 | Mineral Wool | 100.0 | 2.632 | - |
| - | External Surface (Rse) | - | 0.040 | - |
| Total | 100 | 2.802 | - | |