Below are links we think you'll find useful:


National Association of Home Builders (NAHB) is part of a closely connected network of 800 state and local associations serving the needs and interests of local communities across the United States.


AHRI, the Air-Conditioning, Heating and Refrigeration Institute, is one of the largest trade associations in the nation, representing more than 300 heating, water heating, ventilation, air conditioning and commercial refrigeration manufacturers within the global HVACR industry.

AHRI is recognized by the Department of Energy (DOE) and the Environmental Protection Agency (EPA) as an established and trusted independent certification organization. They may periodically audit water heaters in an effort to verify such figures as Energy Factor and First Hour Ratings. These figures may play a pivotal role in home builders' specifications for energy efficient equipment.

ANSI - American National Standards Institute

A private, non-profit membership organization that administers and coordinates the U.S. voluntary standardization and conformity assessment system. ANSI works with many construction and safety standards, such as Flammable Vapor Ignition Resistant (FVIR) compliance. ANSI also set the standard for the BTU/Hr. threshold for residential and commercial water heaters. These standards, supported by various contributing members of the industry, include:

* ANSI Z-21.10.1 - water heaters rated for 75,000 BTU/Hr. or less (residential)
* ANSI Z-21.10.3 - water heaters over 75,000 BTU/Hr. (commercial).

Home Builder Canada

Home BUILDER magazine is the official magazine of the Canadian Home
Builders' Association (CHBA) and the best-read magazine in Canada's
residential construction industry. Providing our readers with breaking
news, building product & tool information, expert columns & analysis,
in-depth industry coverage and commentary.