During the 21st annual Tour of Homes that kicks off this weekend, 40 new homes in Central Oregon will be open to visitors interested in seeing the latest trends in residential construction and design.
In nearly half the homes, visitors will see a trend that many in the residential construction industry say is likely to be a standard for every home someday: a rating that quantifies a home’s estimated energy costs.
The new Energy Performance Score was developed by the Portland-based nonprofit Earth Advantage Institute and makes its Central Oregon debut this weekend. The score has already debuted in Portland.
“It’s kind of like a miles-per-gallon rating,” said Bruce Sullivan, the green-building consultant for Earth Advantage Institute, which developed the Energy Performance Score for the Energy Trust of Oregon. “It’s a really valuable metric … that helps people make good decisions about where to get the most bang for the buck.”
As the nation has focused more attention on vehicle fuel economy in the past few years, the focus on building energy-efficient homes and offices also has increased.
As a result, a number of green-building standards have sprung up, including the U.S. Green Building Council’s Leadership in Energy and Environmental Design certification and the federal Environmental Protection Agency’s Energy Star certification.
Earth Advantage Institute also has its own certification, called Earth Advantage.
All three, to varying degrees, seek to improve a home’s energy efficiency by certifying certain green building steps have been incorporated into the home’s construction.
But what has been lacking is a rating that puts a real number on how much energy a home is likely to consume, said David Heslam, EPS program manager at Earth Advantage Institute.
“The same way you can use the mpg rating to compare between one auto and another, you can compare the energy efficiency of one house to another, by looking at its (EPS),” Heslam said. “In the past, the only way to know what a home’s energy use was was to look at the utility bills, but different families use energy in different ways.”
For instance, a family with three teenagers will use much more hot water than an elderly couple, Heslam said. Hot water, he said, can be as much as 30 percent of a home’s energy use.
To account for usage differences, Heslam said the score uses computer modeling that considers factors such as the house’s size and how many bedrooms it has with average behaviors, such as the average U.S. adult takes 5.3 showers a week.
The end result is a score estimating how many kilowatt-hours of energy it would take to fuel the house for a year.
In an example supplied to The Bulletin, a 2,025-square-foot single-family home with four bedrooms built in Portland in 1958 has a score, or estimated annual energy use, of 27,900 kilowatt-hours per year. According to the example, that translates to an annual energy bill of $1,640.
And for those concerned about their carbon footprint, the score also estimates how many pounds of carbon are released in a year to generate the power fueling the home.
Per the example provided, the 27,900 kilowatt hours used by the home would generate 20,100 pounds of carbon emissions.
Mike Jensen, director of communications for the Central Oregon Builders Association, said homebuyers are paying more attention to green-building ratings. He said the ratings can seem confusing, as they mostly mean different things, but he believes they’re the future.
“Quite frankly, I think (the EPS) is groundbreaking for the homebuilding industry,” Jensen said. “I think eventually, in three to five years, this will be well-known and used as much as the miles-per-gallon rating is used for cars.”
Builder Nate Connolly, with Ridgeline Custom Homes in Bend, said it costs more money to build a home with energy-efficient features, but they provide energy savings over the home’s life. How to measure those savings hasn’t been easy, which is why Connolly also is excited about the EPS.
“It’s probably the answer for an efficiency rating on a home,” Connolly said.
In coming months, Sullivan said the Earth Advantage Institute plans to lobby local real estate organizations, including the Central Oregon Association of Realtors, to make the EPS one of the data points listed with a home when it’s added to the Multiple Listing Service.
Sullivan said an education campaign also would be needed for Realtors, lenders and appraisers.