Older windows can be a huge source of heat loss, and many people looking to upgrade their windows are concerned with energy efficiency as well as the up-front costs. The main difference between single glazed windows vs double glazed windows is obvious: instead of one pane of glass, a double glazed window features two panes of glass separated by a vacuum. The result: better sound insulation and noticeable energy savings while still providing plenty of natural light. Trying to choose the right window solution can be confusing when there are so many options, but the double glazing is often the winner against alternatives like laminated glass and Low-E glass when it comes to energy savings.