Anyone keeping up with ASHRAE standards knows about Standard 90.1, “Energy Standard for Buildings Except Low-Rise Residential Buildings.” But less well known is its sister, Standard 90.2, “Energy Efficient Design of New Low-Rise Residential Buildings.”

The purpose of both is to provide minimum requirements for the energy-efficient design of buildings. Obviously 90.1 concerns commercial and industrial applications, while 90.2 focuses on new residential dwelling units for human occupancy.

But while 90.1 continues to be as high profile and controversial as ever, 90.2 has slipped even further into the background. In fact, there will be an open forum at ASHRAE’s Winter Meeting in Atlanta titled “Is Standard 90.2 Relevant?”

Solid Standard

Like the high-profile Standard 62-99, 90.1 is also under continuous maintenance. That means the committee sorts through the existing standard and comes up with addenda. The public may also submit proposals to the standard at any time, which the committee must review and vote on.

According to Larry Spielvogel, chairman of SSPC 90.1, there have been some significant recommendations and improvements from the public. “The continuous maintenance process gives people an opportunity to jump in and say, ‘We think you did this wrong, here’s why, and here’s what we suggest you do the next time.’”

The committee has also been busy working on the standard to include renovations and additions to existing buildings. When this section is adopted, it means that whenever any equipment (particularly mechanical equipment) is replaced, it must be replaced with equipment that conforms to the standard that would be used for new buildings.

“So, whereas the situation today is if you’re replacing an air-handling unit, a chiller, or a cooling tower in an existing building, there are no restrictions on the efficiency or performance. When the current standard is adopted by the local code authorities, that’s going to change substantially,” says Spielvogel.

More big news for 90.1 is that the International Code Council voted to adopt this standard as the reference in its 2001 supplement to the International Energy Conservation Code. Those jurisdictions that adopt what were the old Building Officials Code Administration (BOCA), International Conference of Building Officials (ICBO), and Southern Building Codes codes, will have the 1999 version of 90.1 available next year. Of course, each jurisdiction has a different schedule for adopting the model codes.

Another effort under way concerns the Model Codes. While they are supplemented every year for the International Energy Conservation Code, they are totally republished every three years. Therefore, one of the committee’s major efforts is to republish the standard by November 2001 so it can be submitted for inclusion in the next published version of the Model Codes, which comes out in 2003.

Battle of Fuels, Environment

Spielvogel expects that discussion at the Winter Meeting may concern some of the controversial aspects of the standard. The main controversy still involves fuels.

Basically, the American Gas Association (AGA) is not happy with the standard and has appealed to the American National Standards Institute (ANSI), which sustained the standard on the first appeal. AGA is now working on a second-level appeal.

Another controversy stems from environmental groups who believe that the standard should be more stringent than it is. “Realize that a standard is a minimum set of requirements,” says Spielvogel. “The environmental groups believe that we should be able to justify more stringent requirements; of course, that engenders considerable debate and discussion. We have some current deliberations about how much more stringent the committee would propose the standard be the next time around.”

Spielvogel notes that addenda containing the continuous maintenance proposals should be out for public review in December. Interested parties can download the addenda from the ASHRAE website ( and provide comments.

“We welcome comments from contractors,” says Spielvogel. “We especially seek technically oriented contractors to volunteer to serve as committee members.”

Struggling Standard

While 90.1 is humming along nicely, 90.2 isn’t doing so well. The reason for that, according to Harold Crowder, chairman of SSPC 90.2, is the fact that the Energy Policy Act of 1992 (EPAct) cites the Council of American Building Officials (CABO) Model Energy Code (MEC) as its reference document for consideration and determination regarding energy efficiency in residential buildings.

“Despite the fact that the MEC had serious shortcomings in addressing cooling issues, it became the reference code,” notes Crowder. “ASHRAE Standard 90.2, on the other hand, does include requirements with respect to cooling.”

Because 90.2 is not the reference standard in EPAct, it is suffering from lack of visibility. The committee would like to breathe life back into the standard, which is why it’s hosting the relevancy discussion on January 25 at the ASHRAE Winter Meeting.

“One thrust of our efforts is to bring the standard up to a level that would have it recognized as an equivalent path for compliance and adopted by reference in the current versions of the MEC, now known as the International Code Council’s Energy Conservation Code [IECC] and International Residential Code [IRC],” says Crowder.

The committee continues to work through some controversial issues as well. The main controversy concerns an addendum that updates the formula for arriving at the amount of energy consumption for water heating in the Annual Energy Cost (AEC) methodology, which is a performance-based path to demonstrate compliance. And, within the AEC, some are considering tradeoffs that should be incorporated between the equipment and the building envelope requirements in lieu of maintaining their independence, as is now the case.

In addition to these issues, Crowder says the committee is working on a significant proposal that would ultimately reformat the entire standard, making it much more user friendly.

“As a result of constantly updating and improving the standard, a number of addenda are in the process of public review, with the ultimate goal of publication,” notes Crowder.

It will be interesting to see what happens at the Winter Meeting with both standards.

Publication date: 12/06/2000