U-value

Calculation of the U-value

The psi-value (Ψ-value) describes the thermal transmittance of an element at the edges (interaction of frame, glass, and spacers). The lower this value, the more efficient the thermal insulation of the element.

The thermal transmittance coefficient U (U-value) of an element is calculated using the following values:

• U_f-value of the entire frame area (inside or outside)
• U_g-value of the visible area of the glazing
• Thermal transmittance psi / Ψ

The lower the U-value, the more efficient the thermal insulation of the element.

U-values of the element

• Open a position.
• In the "Element" section, on the "Edit" tab, click "U-value":
  
• At the top of the following overview, the U- and Psi (Ψ)- values for the position are listed:
  
• Below this overview, achievable values when using other gasket variants are listed.
• At the bottom, the U_g/U_p-values for the fillings used in the position are listed.
• Click "Excel" to open the U-value overview in an Excel spreadsheet.
• Click "Details" to display the assignment of the U-values to areas:
  

Display U-Values in position drawing

• Open the "View" tab and select the "U-value" option to display the U-value of the element in the workspace of the position drawing: