However, with modern energy-efficient windows, you’ll take advantage of sunlight and avoid excessive heat loss through the pane. This could cut your heating bill by as much as 25 to 30 percent compared to older windows. How energy-efficient, windows are, depends on a number of things.
» Look for the U-value
When buying energy efficient windows, you should look at the U-value of the window. The U-value is a measure of how much heat is lost through the window, and the lower the U-value the better the insulation.
VELFAC glazing offers a U-value as low as 0.8 W/m2k, one of the best in the industry today.
» Other energy-reducing features you should look for
Low U-values always indicate excellent insulation, but you should also look for the additional features that can improve energy performance further:
• Double-glazing or even triple-glazing to ensure exceptional weather or acoustic insulation;
• Slim frames reduce U-values, as glass is a better insulator than the frame. They also let significantly more daylight into your house, cutting energy bills further;
• Big windows exploit solar energy better, as they let more sunlight in;
• Coated glass can reflect unwanted solar gain, or reflect heat back into the interior;
• Glazing units filled with argon gas further improves insulation;
• Optional glass coatings to reflect heat back into the interior, or to control solar gain.
» Don’t forget the window positioning
Energy performance can also be improved by positioning the windows strategically in relation to the sun:
• South facing windows receive the biggest inflow of sunlight;
• East facing and west facing receive about the same inflow of light;
• North facing windows don’t receive direct sunlight.
Big, south facing windows take full advantage of the sunlight and heat, which could give you significant savings on energy for heat and artificial lighting. To get comfortable lighting in a room, you’ll generally want windows facing towards two or more corners of the world.
» Choose energy efficient windows
At VELFAC, we’ve been designing low energy windows for over 50 years. Our windows offer exceptional insulation, with double-glazing as standard and triple-glazing also an option.
The distinctive slim VELFAC frame not only looks good but also maximises daylight, reducing the need for artificial lighting, while minimising cold spots within a room.