Most green home programs follow the “Green Home Building Guidelines” of the National Association of Homebuilders (NAHB). Developed earlier in this decade, the NAHB’s green guidelines form the basis for dozens of local certification programs run by local home builder associations. (There are also established green home certification programs run by local utilities, such as Austin Energy in Texas, the oldest program in the country.) The NAHB’s guidelines divided the green home assessment program into seven guiding principles, using a point-based rating system.
- Lot design, preparation and development.
- Resource and materials efficiency.
- Energy efficiency.
- Water efficiency.
- Indoor environmental quality.
- Operation, maintenance and homeowner education.
- Global impact of products used, including low-VOC paints and sealants.
For certification at the Bronze, Silver and Gold levels, the NAHB guidelines require minimum point totals in each of the seven areas of concern, plus 100 additional points from sections of a builder’s choice. As expected, minimum energy-efficiency points are by far the largest single component of the system.
Civano community in Tucson, Arizona, is an early (1990s) example of a New Urbanist walkable, green home development with clear energy-efficiency and water-conservation guidelines, narrow streets and local businesses near the town center. Individual homes were constructed and sold by four local builders. A second 600-home phase is underway in 2007, using the same guidelines. (Photo courtesy of Civano Community)