Alaska homeowners used to boasting about their five-star-plus energy ratings will have a new high-water mark come July 1.
In April, the Alaska Housing Finance Corp., which manages two immensely popular energy efficiency programs, increased its energy standards for homes. Now, participants in one of the rebate programs can receive six-star ratings on newly constructed homes and get $10,000 back for their efforts.
Under changes adopted by the corporation, Alaska homeowners participating in the Home Energy Rebate Program for new construction may qualify for the coveted rating beginning next month. It will be awarded to homes meeting the highest standards.
Previously, the highest rating recognized by the corporation was a five-star-plus, which allowed new homeowners who qualify to get $7,500. Applications filed after July 1 can expect to receive a $7,000 rebate for obtaining one of those five-star-plus rating.
The rebate program began in May 2008. In the roughly four years since, until June 30, 2012, more than $137 million has been spent through the program. During its initial year, more than 1,000 people were on the program’s waiting list. AHFC has since curtailed its ambitions. The waiting list was cut to 500, so workers could manage the large applicant pool efficiently.
AHFC uses the Home Energy Rating System index, a nationally recognized scoring card for measuring homes’ energy performances, to determine its star ratings. It’s a 100-point system, with points awarded for thermal resistance, air leakage, moisture protection and ventilation. Between 92 and 94.9 points grants homeowners a five-star-plus, and everything above now gets the six star rating.
Alaskans can apply for the rebate program to make improvements on existing homes, or build new homes hewing to high energy efficiency standards. Participants who improved existing homes to a five-star-plus rating already could receive $10,000.
Both existing homes and new construction can obtain the new rating and the maximum payout, said Jimmy Ord, the corporation’s energy information officer.
At its April meeting, the corporation’s board of directors unanimously increased the building energy efficiency standards, or BEES, for homes. It also brought the standards in line with the 2012 International Energy Conservation Code, which includes amendments special to Alaska.
Ord said there had been significant changes to the methods and materials used to improve homes’ energy efficiency over the past couple of years.
The biggest change is greater use of exterior insulation, said Jack Hebert, owner of Hebert Homes and founder of the Cold Climate Housing Research Center, a nonprofit corporation that studies energy-efficient building technologies.
Builders generally use rigid foam insulation on exterior walls. Often called foam boards, they’re used to fill extra space in buildings, as well as increase energy efficiency.
It’s now common to build tighter homes with whole-house ventilation systems, Hebert said. And part of building a snug structure is exterior insulation.
The research center’s staff often receives questions about retrofitting homes with additional insulation to save on heating bills. One method involves adding foam insulation to the exterior of homes, but determining how much insulation to add can be tricky.
In Fairbanks, walls constructed of 2x6 boards would need between six and 10 inches of exterior foam board. Unfortunately, the method is expensive, and there’s mold to worry about, too. Adding exterior insulation can produce moisture damage by reducing the ability of the combined materials -- gypsum, plywood sheathing, and interior insulation -- to release trapped moisture.
“If people hire a builder, they need to be up to speed on the techniques,” Hebert said, “and most contractors with residential endorsement in the state understand; they have to take tests and do continuing education.”
In Southeast Alaska, there has been an increase in air-source heat-pump installations the past few years, according to a 2013 research center study. These systems transfer heat from outside a building to inside, or vice versa.
Recent advances in technology have resulted in heat-pump models capable of producing heat efficiently in temperatures below freezing.
Overall, heating systems have become more efficient. The size of appliances has been reduced, too, as buildings demand less heat, Hebert said.
Other factors that led to the six-star rating include the public’s desire to improve the longevity of Alaska homes, existing or new. Many last 50 to 80 years if they’re built “right” in the first place, requiring less maintenance and less money for heating, Ord said.
“I could rattle off 100 different reasons why to (make an effort to improve homes): the cost of the home, the lifespan of homes. You’re hedging your bets against the future of energy security. If you use less of a resource, you won’t be as prone to the fluctuations in cost.”
But the differences between a five-star-plus and six-star rating are difficult to pinpoint, Ord said. Rather than focusing on specific increases, homeowners seeking the highest rating take a holistic approach to improvements.
It’s an all-of-the-above workload that includes more insulation, installing a high-end ventilation system, better windows, and so on. “It’s hard to be specific about the rating,” he said. “One improvement may be integral to the next.”
Contact Jerzy Shedlock at jerzy(at)alaskadispatch.com