Windows
Nationwide, heating and cooling energy attributable to windows account for about ten percent of energy consumption in buildings; when daylighting potential is considered, it can be even more. Efficient windows can lower heating and cooling energy while maintaining daylight and view.
Lower Heating and Cooling Costs
Windows are a major driver of building energy use. As they typically transfer heat much more easily than do insulated walls, window energy performance is of particular concern to heating and cooling energy use. Additional factors like solar heat, daylight and ventilation are important to consider for building energy performance.
Many window technologies can increase the insulating properties of windows. While most people realize that double-pane and triple-pane windows are more efficient than single-pane windows, other components can significantly improve window efficiency as well.
As it currently stands, the seven-story brick box apartment complex in Boston’s South End hardly strikes the onlooker as an example to be replicated. But this is set to change as the 192-unit Castle Square Apartments receive a deep energy retrofit to elevate the city block’s attractiveness, comfort conditions and energy performance.
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Single-family homes or duplexes typically attract the most attention from energy efficiency programs such as ENERGY STAR or utility rebates. Nevertheless, the importance of energy efficiency, including efficient windows, for multifamily housing is increasingly being recognized.
