"ASHRAE's participation is welcome news for the home building industry," said NAHB Chairman Kevin Kelly, a home builder and developer in Wilmington, Del. "This cements the position of the National Green Building Standard as the preeminent green standard for residential construction."

The NAHB and ICC started drafting the standard in 2007 with the input of builders, code officials, product manufacturers, building scientists, energy-efficiency specialists and government officials.

The resulting work was approved by the American National Standards Institute two years later. It was updated in 2012 and more than 32,000 single- and multifamily homes have been OK’d under the program.

The addition of the ASHRAE’s green HVAC market expertise boosts the standard’s prominence, according to a statement from ICC board President Stephen Jones and CEO Dominic Sims.

"As one of the nation's leading societies for building technology, ASHRAE brings years of experience and knowledge to the table, particularly in the areas of indoor environmental quality and energy efficiency," the men said. "ASHRAE's welcome involvement will help position the ICC/ASHRAE 700 National Green Building Standard even further ahead as the leading consensus standard in the industry."

Society President Bill Bahnfleth echoed the ICC officials’ comments.

 "ASHRAE is pleased to stand beside NAHB and ICC as a co-sponsor of ICC/ASHRAE 700," Bahnfleth said. "This collaborative agreement provides a path forward for ASHRAE to contribute its technical and standards expertise to support one of the most important sectors of the built environment — our homes. We look forward to this joint effort to promote sustainability in the residential sector."