March 19, 2009 | GBI Insight Home

NAHB Announces ANSI Approval of National Green Building Standard™
for Residential Construction

After more than a year of technical review and deliberations, the American National Standards Institute (ANSI) has approved the National Green Building Standard for residential construction. Developed by the National Association of Home Builders (NAHB) in cooperation with the International Code Council (ICC), the standard covers single-family homes, apartments and condominiums, land development and remodeling.

"Approval of this standard gives mainstream home builders a more expansive set of tools for building and certifying green homes," said GBI president Ward Hubbell. "It supports the NAHB's national green building program, NAHBGreen, and ensures that builders nationwide have access to a comprehensive green building program designed specifically for them."

Similar to the NAHB Model Green Home Building Guidelines, the standard requires builders or remodelers to incorporate a minimum number of features related to energy, water and resource efficiency, lot and site development, indoor environmental quality, and homeowner education. The more points earned, the higher the overall rating. However, the standard also includes more mandatory items and suggests higher thresholds in several categories. For example, the following tables highlight the points required for green buildings and subdivisions:

Threshold Point Ratings for Green Buildings

Green Building Categories			Performance Point Levels (1) (2)
			BRONZE	SILVER	GOLD	EMERALD
1.	Chapter 5	Lot Design, Preparation, and Development	39	66	93	119
2.	Chapter 6	Resource Efficiency	45	79	113	146
3.	Chapter 7	Energy Efficiency	30	60	100	120
4.	Chapter 8	Water Efficiency	14	26	41	60
5.	Chapter 9	Indoor Environmental Quality	36	65	100	140
6.	Chapter 10	Operation, Maintenance, and Building Owner Education	8	10	11	12
7.		Additional Points from Any Category	50	100	100	100
Total Points			222	406	558	697
(1) In addition to the threshold number of points in each category, all mandatory provisions of each category shall be implemented.
(2) For dwelling units greater than 4,000 square feet (372 square meters), the number of points in Category 7 (Additional Points from Any Category) shall be increased in accordance with Section 601.1. The "Total Points" shall be increased by the same number of points.

Threshold Point Ratings for Site Design and Development

Green Subdivision Category		Performance Point Levels
		One Star	Two Stars	Three Stars	Four Stars
Chapter 4	Site Design and Development	79	104	134	175

In addition to defining which green practices can be incorporated into residential development and construction, the standard also includes information on the operation and maintenance of green homes. It also has built-in flexibility, allowing for choices based on climate and geography as well as budget and aesthetics.

As part of the formal ANSI process, NAHB and the ICC established a consensus committee of builders, architects, product manufacturers, regulators and environmental experts. The work of the committee was administered by the NAHB Research Center, which is an ANSI-accredited standards developer. The consensus committee deliberated the content of the standard for more than a year, held four public hearings and evaluated more than 2,000 public comments.

For more information or to order a copy of the standard, please visit the NAHB Web site.

Source: NAHB