Are you tired of high utility bills while cooling homes and offices in summer and heating them in winter? If yes, here’s how you can save money by selecting and installing the right energy efficient windows.
It’s because windows gain and lose weight through convection, conduction, air leakage and radiation. There is a unit describing this heat transfer in windows called u-values.
In fact, a window’s performance is gauged by its u-value. It even determines the eco-friendliness of exterior lights, skylights and other exterior components of your home like exterior walls.
What is u-value?
The u-value determines how much heat the entire window transfers. This doesn’t mean just the glass, but includes its frame, glass and sash. Generally windows with a lower u-value are more insulated. They are better at retaining heat in your home in winters, and effectively keep heat out in hot summers.
Traditional windows with metal frames are relatively poor thermal insulators. They don’t keep heat out in summer or retain heat well in winter. This is because its metal frames, which are good conductors of heat, get hot to touch because of the sun’s heat.
However some companies now produce more energy-efficient eco-windows. These windows have plastic or timber frames which are poor conductors of heat. These windows have a low U-value because it stops heat transfer from the heat-exposed side to the non-exposed side.
Typically windows with a u-value falling between 2.0 and 10.0 but eco-windows may have a u-value as low as 0.8. This is how and why they play an important part in eco-friendly and low-energy building strategies.
Eco windows make a great investment
Another important value to ascertain before buying eco windows is its solar heat gain coefficient or SHGC. It indicates how well the window blocks the sun’s heat from passing through the windows and warms the interior. Windows with lower SHGC levels transmit less solar heat.
The goal is to prevent unwanted heat from entering the house during hot climates so that you don’t rely much on artificial cooling. In case of cool climates, the aim is to retain the heat as much as possible and to maximize solar energy penetration into the room.
In case of mixed climates, the aim lies in preventing heat from escaping during winter, and heat from entering the house in summers. In a nutshell, windows with a low U-value and SHGC are always a better buy.
This is especially if you need the AC to keep yourself cool in summer or on a heating system to keep warm in winter.