WASHINGTON - Most U.S. consumers recognize the Environmental Protection Agency's blue Energy Star label when it is posted on an energy-saving refrigerator, water heater or other appliance.

But the program reached a major milestone on Tuesday when the agency marked the one millionth home to be built with the Energy Star label.

Energy Star homes are least 15 percent more efficient than traditional houses and have thick insulation, usually double-paned windows, tight construction and ducts and energy-saving heating and cooling equipment, along with lighting and appliances that use less energy.

Since the Energy Star program began labeling homes in 1995, consumers have cut their energy costs by $1.2 billion and reduced greenhouse gas emissions by 22 billion pounds, which is equal to taking 1.8 million vehicles off the road, EPA says.

Energy Star is a way that the average home buyer can lower their bills (and) at the same time joining in the fight against climate change, EPA Administrator Lisa Jackson told Reuters in an interview.

Jackson acknowledged some Energy Star homes cost more to build, depending on the market. But she said owners recoup that extra expense within five years from savings on energy bills.

Jackson said homebuilders are even using the Energy Star label as a marketing tool to make their properties stand out.

You're looking for a way to attract buyers? As the market recovers we see builders that are looking at the Energy Star label as something additional that their product offers, she said.

About 17 percent of all U.S. single-family homes built last year earned the Energy Star label, up from 12 percent the year before, according to the EPA.

There are about 6,500 builders across the United States that construct Energy Star homes.

The top 5 markets with the most Energy Star homes built to date are: Houston (144,000), Dallas-Fort Worth (103,000), Las Vegas (80,000), Phoenix (73,000) and greater Los Angeles

(57,000).

(Reporting by Tom Doggett)

Energy