In 2005 the NAHB developed the Model Green Home Building Guidelines for the
incorporation of GREEN building practices into the design and construction of
new homes. With market demand for environmentally friendly building products
on the rise, the Model Green Home Building Guidelines are helping move these
products and building practices into the mainstream marketplace by providing
individual builders with a "how to" template on GREEN building.

The Model Green Home Building Guidelines contain seven primary sections:

1. Lot Preparation and Design
   
2. Resource Efficiency
   
3. Energy Efficiency
   
4. Water Efficiency and Conservation
   
5. Occupancy Comfort & Indoor Environmental Quality
   
6. Operation, Maintenance, & Education
   
7. Global Impact
   

These seven guidelines are intended to educate and lead builders through the
process of GREEN construction. The guidelines offer advice, detailed benefits of GREEN building, and clarification on the more complex components of environmental design. Local organizations often adopt the Model Green Home Building Guidelines as a foundation for the creation of their own Green Building programs.

The Model Green Home Building Guidelines are the basis for the "Green Scoring Tool," which assigns points values to building materials and methods used during the construction process depending on their "GREEN level". The Model Green Home Building Guidelines contain three levels of GREEN building, which are determined by a number of total accrued points:

Bronze (237-310 Points); Silver (311-394 Points); and Gold (395+ Points)

Generally the more eco-friendly a product or method is, the higher its GREEN level. For example, points are awarded for using renewable wood products from within the region of a jobsite because it saves fuel and conserves transportation energy. There are a minimum number of points required in each of the seven sections to make certain the GREEN building process is balanced and thoroughly executed.