Low-Cost Green Strategies: Windows & Daylighting
05/11/2009 by Andrea Sillah
The measures listed here are economical in terms of both first costs and life cycle costs. Also worth noting is that a key factor in a successful, cost-saving green facility is the integration, early in the building design process, of all systems for optimal results.
- In selecting the features that pay back on initial investment, look for high insulation value (R value; aim for R-5 or R-6) and a low-E (or low-emissivity) coating, which allows light to pass through, but reflects heat.
- Select windows based on the orientation of each of the building’s walls and the amount of solar radiation, as well as the local climate.)
- Invest in operable windows for natural ventilation that can reduce the need for air conditioning and maximize the benefits of fresh air. Position windows to enable cross-ventilation.
- Include sun screens or overhangs to shade windows that face south, thereby reducing heat gain in summer.
- Caulk windows, doors, and any other openings in the building envelope with a low-toxicity material to prevent air leaks.
This technique, capturing natural light to minimize artificial light, is most effective with tall windows and windows positioned close to corners so they can bounce light off of the nearest wall. Skylights are good options in corridors and stairwells.
Look for more articles in this series to come. For more low-cost green strategies, check out Green Building: Project Planning & Cost Estimating, 2nd Edition.