ATLANTIC CITY, NJ — American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 90 was originally a single document. Then it was split into 90.1 and 90.2. A forum at the 2002 ASHRAE Winter Meeting asked, “Should Standards 90.1 and 90.2 Be Combined Into A Single Standard?”

The discussion centered on whether it would be advantageous to bring the two standards back together again. Standard 90.1 covers nonresidential buildings, while 90.2 is for residential buildings. The federal government has required states to adopt Standard 90.1 into their codes. However, the Model Energy Code, published by the International Code Council, is being used instead of 90.2.

An engineer noted that 90.1 was made prominent by the states and many readily adopted it. But 90.2 is not used, even though it is about 10 years old.

What would change in a combined document? Not much, was the response, just a small amount of additional wording. For the bulk of the requirements, there will need to be some editing, an official said, but it would not be that difficult to combine the two standards. The equipment requirements were said to be “essentially identical.”

The building envelope issue is something that needs to be addressed because it is different for 90.1 and 90.2.


“The logic of splitting them up was very valid,” said an engineer. “The logic of wanting them to be simple is also valid. But if we combine them, it might make it much more complicated and likely to be ignored.”

We need to market 90.1 and 90.2 to get more people to pay attention and apply them, another stated.

A person who does code work asked, “What’s in the best interest of ASHRAE in this issue? ASHRAE may be perceived as not moving fast enough.”

An official said it is difficult to make comparisons between 90.2 and the Model Energy Code. He conceded that the Model Energy Code is simpler.

A builder commented that you’ve got to show builders and contractors that 90.2 is a code they can understand. Simple language is needed. When people see the name ASHRAE on a document, they assume it’s written for engineers.

A city official said that the standard needs tables that are easy to access. It was suggested that 90.2 items be placed in a separate section and that this shouldn’t require a lot of extra pages if the standards are combined.

One member said that regarding standards, “One of our jobs is to make all of the special interests equally unhappy.”

A federal official remarked that the federal government moves very slowly. “Don’t count on them for anything regarding 90.2, except getting in your way.”

Look for more coverage of the 2002 ASHRAE Winter Meeting in future issues of The News.

Publication date: 03/11/2002