Construction build-up (inside to outside)
Material
Thickness (mm)
λ (W/mK)
Label (optional)
Cross-section
0.00
Calculated U-value (W/m²K)
Pass
Insulation quantity & cost
0 mm
Total insulation thickness
0.00 m³
Insulation volume needed
£0.00
Estimated material cost
Target U-values are illustrative, commonly-cited approximate Part L reference figures for
new work/renovation, not a certified compliance check - always check the current Building
Regulations edition applicable to your job, or get a proper SAP/RdSAP assessment, before
relying on this for sign-off. Material λ values are typical figures and vary by
product - check the manufacturer's declared value for anything you actually specify or
order.
Material presets
| Material | Typical λ (W/mK) | Category |
|---|
Element types & target U-values
| Element type | Target U-value (W/m²K) | Surface resistances (Rsi / Rso) |
|---|