The coating allows sunlight to pass through, but keeps heat from passing out. It also keeps inside window surfaces warmer, and reduces the potential for condensation. The window frame itself provides structure and holds the glazing in place. Glazing consists of one or more panes of glass, with each pane separated by a spacer. In between the frame and the glazing is the sash.
Windows are extremely vulnerable.
A home could be fitted with the most energy efficient windows on the market, but if it is installed poorly it will not be effective and could be damaging to the home. Windows that are installed upside down or backwards or slope into the building instead of away from it will leak. Likewise, if a window is completely airtight, once water gets behind the window frame it has no way to escape. The results may be wood rot, mildew and condensation. Take the time this winter to ensure your windows are working properly and offer energy saving benefits.