Federal agencies and the Bush administration want everyone to conserve energy now that Hurricane Katrina has caused a run-up in gasoline prices and Americans face high heating prices this winter.

This month, White House staffers were told to carpool and to turn off the lights when they leave a room. The Environmental Protection Agency promised to remove unnecessary hallway light bulbs and to keep thermostats at 68 degrees. The Department of Energy is sponsoring an "Easy Ways to Save Energy" campaign directed at homeowners, businesses and the government.

That's why several groups that promote energy conservation, and some members of the insulation industry, are furious that the Bush administration passed up a recent opportunity to make new homes more energy efficient by not supporting a proposal to increase the efficiency of wall insulation in certain areas of the country.

The Energy Department issued a statement on Sept. 28, the day before a key vote by a code-setting body, saying it could not support more stringent "R-values" -- which measure the resistance of insulation to loss of heat -- because there is "still inadequate data on the cost and implementation" of the increase.

The department has played a central role for the past 30 years in proposing code changes and supporting states in upgrading building codes, so any comment it makes on a code proposal carries weight. In fact, energy conservationists say the statement sunk their plan to make homes more energy efficient.

"We were disappointed that DOE supported an effort to weaken the energy code when home heating fuel prices are at a record high," said Bill Prindle, deputy director of the American Council for an Energy-Efficient Economy, a nonprofit research group. The organization accused the department of backing the National Association of Home Builders, which opposed raising the R values.

David Garman, the Energy Department's undersecretary for energy, science and environment, said in an interview that there isn't any link between the country's energy woes and a change in the energy code, which would take years to have an impact. Garman said the department was neutral in the code debate.

At issue was a proposal Prindle's group made to the International Code Council, which was in the process of updating the nation's model energy code. It called for increasing levels of wall insulation to R-15 from R-13 and to R-21 from R-19 in the central and northern climate zones of the country. The council, with input from the Energy Department, issues model building codes that set minimums for safe building practices, fire prevention and energy efficiency.

The group asked for higher insulation standards after the Energy Department proposed to simplify the International Energy Conservation Code in 2003 to make it easier for states to adopt and for builders to apply. One of the department's changes was to allow the installation of glass in new homes without upgrading the wall insulation to offset energy losses. Energy efficiency groups thought higher R-values of insulation would compensate.

The NAHB, which represents the building industry -- and declined to be interviewed -- immediately opposed the idea to increase the insulation value and called on the Energy Department to analyze its cost effectiveness.

Garman said that undersecretaries normally do not get involved in the minutia of code changes but that this issue had generated "so much ill will among the stakeholders" that he ordered a study. In fact, a small war among the home builders, insulation trade groups, energy-efficiency advocates and the Energy Department was about to break out.

The study results, posted on the Energy Department's Web site in February, dovetailed with what the home builders had been saying: The increase in insulating properties would hamper use of some common types of insulation. And it would take 40 to 90 years to recoup the investment, while energy savings would be a modest $15 per home.

The NAHB was delighted with the results. It began an aggressive lobbying campaign to persuade council members to roll back the proposal and said in its "talking points" that "DOE agrees this is a bad change . . . ."

But the group got a jolt on Sept. 26, when the agency unexpectedly took the study off its Web site, saying it needed further study and more information on costs.

The energy-efficiency proponents viewed the department's statement saying it couldn't support the higher insulation standard as a betrayal that eroded support for their proposal and led to its defeat at a full meeting of the Code Council in Detroit. The vote was 271-68 against the increase in R-values. The NAHB called it a victory for housing affordability.

But the builders continued to steam over the department's backing away from its study. In retribution, Garman said the NAHB confirmed, the home builders' group cancelled its support of a high-profile event associated with the Energy Department's solar decathlon on the Mall last week.

Garman bemoaned how bloodied the department was in this battle. He said he regretted -- and was even embarrassed -- that the agency could not have delivered reliable technical analysis in a more timely way. He said the department's technical staff did not have confidence in the results of the study -- particularly after groups on both sides tore it apart with their own findings. A revision will be posted this fall, he said.

The cycle leading up to more code revisions begins again next year. "We will come back with other proposals, and one of the drivers will be astronomical increases in natural gas prices," said Harry Misuriello, who is with the Alliance to Save Energy, a nonprofit group that promotes energy efficiency. "The codes need to keep pace with energy cost increases."

"We want to take the high road . . . to help consumers ask [builders] for energy-efficient homes and for builders to build them," Garman said. "When we have these kinds of disputes in the code-setting arena, it hurts us."