Online U-value calculation

Choose the type of surface

Mechanically fixing






Thickness Lambda value R-value
Rtot [m²K/W]
[mm] U-value not adjusted [W/m²K]
[mm] Correction term measuring and placing [W/m²K]
[mm] Correction term air holes [W/m²K]
[mm] Correction term mechanic fixation [W/m²K]
[mm] Adjusted U-value [W/m²K]
  • Indicative calculation based on NBN B62-002. The listed values can be different from the actual values.
  • Always introduce the total thickness, e.g. two layers of insulation of 82 mm gives 164 mm.
  • This program has been performed with the greatest care, but errors can't be completely excluded. Therefore Recticel Insulation can't be held responsible for any errors.
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