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U-Value / R-Value Builder
Build up U-values and R-values layer by layer per BS EN ISO 6946, with an optional Part L limiting-U check.
The Ensign ToolboxU-Value / R-Value BuilderBuild up U-values and R-values layer by layer per BS EN ISO 6946, with an optional Part L limiting-U check.
Element
W/m²·K
Overrides the limit above — check against a project spec
Surface resistances (optional overrides)
m²·K/W
ISO 6946 Table 7 default by direction
m²·K/W
0.04 default; ~0.10 for a floor over unheated space (BR 443)
Layers (outer → inner)
No layers added yet
Add at least one complete layer to build the U-value