The SHGC or Solar Heat Gain Coefficient is a measure of the amount of heat that can be gained through your windows at times of direct solar contact. The SHGC is important as during summer the SHGC can add large amounts of unwanted heat to your house. Equally in winter the SHGC can be utilised to provide cost and pollution free heat from the sun. The Solar heat gain is measure as a coefficient and indicates the amount of direct solar heat that will penetrate your house.
The U-Value or Uw is a measure of conductivity of the whole window (glass and frame included). It is a number calculated to return an amount of energy flowing through the product at a given temperature difference per meter squared of window. The Uw is a number that indicates how well a window or door will retain heat in the winter and reject heat during summer. The lower the Uw the better the energy efficiency of the product.
If you’re looking to add value to your home while reducing your energy costs, one way is to install double glazed units. What is a double glazed unit? This is just a fancy term for two glass window panes separated by air or other gas, designed to reduce heat transfer, thereby lowering your heating bills. And if you’re thinking of future resale value (which you always should be, regardless of how long you’re planning on staying in your current home!), lowered energy bills will certainly attract interested buyers.