- Acoustic insulation index : R
- Cekal acoustic classification
- Self-cleaning glass
- Scratch resistant glass
- How glass breaks
- Safety classification
- Vandalism resistant glass
- Break-in resistant glass
- BRS bullets resistant glass
- BRNS bullet resistant glass
- SG & SGNS bullet resistance
- Fire resistance
- Reaction to fire
- Thermal insulation classes
- Light Transmission
- Thermal transmittance
- Solar factor g
- Triple glazing
- Warm edge
All about glass > Thermal transmittance : U value
Heat loss is normally measured by the thermal transmittance or U value, calculated according to EN 673. The lower the U value, the greater the thermal insulationIf a glazing has a thermal transmittance U = 2 W/m².K
It will be necessary to produce 2 watts of heat per square meter to make up for 1 degree Kelvin difference between the inside and outside temperature.
Ug (g=glass) is the thermal transmittance of the glass expressed in W/m2.K
Uw (w=window) is the thermal transmittance of the window expressed in W/m2.K
We will use U=Ug