Thermal performance

  • Thermal transmittance Ug
The thermal performance Ug of insulating glazing (double or triple) depends on the emissivity of the coating used, the dimensions of the space(s) between the glass and whether or not argon gas is present.
This thermal performance is expressed in the form of the value Ug, which contributes significantly to the window's thermal performance (Uw). It is calculated according to EN 673 standard.
A Ug of 1.1 means that the energy loss is 1.1 Watt per square metre Kelvin (in conventional conditions).
  • Reinforced thermal performance classes W/(m2.K) in ascending order of performance, in CEKAL certification.
There are 14 Thermal Reinforced performance classes for glazing, characterised by the thermal transmittance value Ug:   Ug 0.6 to Ug 1.9 (TR1 to TR14).