Energy Efficiency

VELFAC Windows can provide U-values as low as 0.8W/m²k, however, a window is not like a brick wall, where the focus is simply on the ability of that wall to keep the cold out and the warmth in.

Windows play a crucial role in reducing a building's heating consumption to the lowest level possible. Besides the window's basic energy performance, the primary factors to consider in low energy buildings are:

  • The windows' orientation in relation to the sun 
  • Sun screening and shading 
  • The glass ratio 
  • Installation methods and thermal bridges 
  • The number of windows and total window area 
  • Air tightness 

Below is a diagram explaining the window energy terminology:

Diagram of window energy terminology