An odd legal twist to energy efficiency requirements has temporarily stalled Santa Fe's proposed green building code.

Last week, a team of builders and Santa Fe city staff were ready to present a set of proposed standards for energy- and water-efficient houses to the city's business committee when they found out the bad news: A federal district judge had granted a temporary injunction to stop Albuquerque from using its new green building code.

Albuquerque's green building code was to become effective Oct. 1.

The Air Conditioning, Heating and Refrigeration Institute and several distributors sued Albuquerque on Aug. 29 over the green building code claiming it sets energy efficiency standards for furnaces, water heaters and air conditioners that are more stringent than those allowed under federal law.

In an era when higher energy efficiency is all the rage, suing over more efficient heating and cooling systems may seem backward.

But for manufacturers who ship equipment across state lines, a national heating and cooling appliance standard prevents problems, according to the lawsuit.

The heating and cooling groups claim standards set under the federal Energy Policy Act and the Public Health Act trump Albuquerque's code.

Typically, the federal government sets a minimum health standard for things like cars, toys, food and more. States and municipalities can set stricter standards, but not more lenient ones.

Mortimer said there appears to be one exception under the Public Health and Welfare Act: Energy efficient appliances. For those, the federal law sets a ceiling on the energy efficiency of dishwashers, furnaces, clothes washers and other large appliances. States and municipalities can not create standards more restrictive, the opposite of the rest of the law. "It appears to be the only portion of the law that sets a bar," said Katherine Mortimer, Santa Fe's supervising long-range planner.

Albuquerque argued that not implementing the green code would hurt consumers, making them pay for builders' environmentally unfriendly practices.

But federal District Judge Martha Vázquez in part ruled that the harm to the heating and cooling manufacturers and distributors would be greater if the code stands.

Mortimer said the ruling appears to halt Albuquerque's entire code until the legal issues are resolved. She said the city went after a green building standard for all types of structures at once — residential, commercial, new and renovated. She thinks that's one reason it ran into legal trouble.

Santa Fe wants to avoid a similar lawsuit.

Mortimer thinks most of Santa Fe's proposed code won't run into the same legal challenge as Albuquerque's because they approached changing the code differently. "We decided to take it one step at a time and focus on homes. Most new construction in Santa Fe are homes," she said. "We want to perfect this code and then add commercial buildings, remodels and others."

Both Albuquerque's green code and Santa Fe's proposed one require builders to meet certain energy efficiency standards, among other factors, to be approved.

Santa Fe's proposed code bases the energy efficiency around a Home Energy Rating System test known as HERS. The proposed code would require new homes up to 3,000 square feet to achieve a HERS 70 rating, making it 30 percent more energy efficient than the current code-approved home. Homes 3,001 to 5,000 square feet would need to meet a HERS 50 rating, 5,001 to 8,000 would need a HERS 25, and over 8,000 square feet a home would need to be net zero energy home.

Santa Fe's proposed green building code, modeled on a national and state code created by home builders associations, sets standards not only for energy efficiency but siting, materials, indoor air quality and water conservation.

To make sure the city's proposed code won't be challenged on the same energy efficiency grounds as Albuquerque's, a certified HERS rater is testing the code on computer-modeled homes.

Dalinda Bangert, a HERS rater and owner of EcoTerra Enterprises in Santa Fe, said she'll test Santa Fe's code on a typical frame house in various sizes. The software she uses tells her how much energy can be saved with various changes such as insulated windows, passive solar design, different light bulbs and appliances. Bangert and Mortimer believe it is possible to reach the HERS 70 and HERS 50 score without requiring builders to install high-efficiency heating and cooling systems. But that might not be true of a lower HERS rating.

"It's a performance-based code," Bangert said. "We're rating the energy performance of the overall house. The question is: Can we get to the HERS rating of "x" without putting in a 90 percent efficient furnace?"

Mortimer said once Bangert has finished testing the green code and the attorney reviews it, the green building group will present it again to city committees for approval.

Santa Fe's attempts to create a green building code is part of the city's "Sustainable Santa Fe" plan. That plan, created with public input, goes to the City Council for a vote on Oct. 29.

Contact Staci Matlock at 470-9843 or smatlock@sfnewmexican.com.