BELLINGHAM - Habitat for Humanity in Whatcom County is building its first "passive" home - a house so energy-efficient that it is expected to cost about $98 a year to heat.

The 1,200-square-foot house on West Indiana Street in the Birchwood neighborhood is a partnership with Kulshan Community Land Trust.

The Bellingham home should be completed spring 2013.

Jaime and Leandra Huante, now living in Ferndale, will then move in with their three children. Jaime is an agricultural worker, and Leandra works two jobs at a gym and a church.

The Huantes are renting a two-bedroom home with no insulation that they heat with space heaters. The children sleep in their parents' room during winter because their north-facing room is too cold, according to Habitat.

Passive design, which comes from Europe and is growing in popularity in the U.S., is lauded for making homes super energy-efficient by, in part, making buildings very airtight.

Habitat's builders will put in double walls, extensive insulation, high-tech windows and an air-to-air heat exchanger (versus a traditional furnace).

Habitat for Humanity in Whatcom County is doing its first "passive" build out of a desire to be as green as possible, according to John Moon, executive director for Habitat here.

The home will cost about $12,500 more to build than a traditional home of the same size, so Habitat had to consider the cost burden such a building method would impose on the families they're trying to serve, according to Moon.

But the energy efficiency is expected to make such homes less expensive to own over time, compared to homes built with traditional construction techniques.

"The savings in the heating bill is more than enough to cover the additional cost of construction," Moon said. "We feel that we can make this work for low-income families."

That's because of the expected energy savings as well as Habitat's zero-percent mortgage, Moon noted.

The Building Performance Center, a division of the Opportunity Council, also worked on the project with Habitat by running computerized energy audits.

John Davies, the center's manager, said that the construction industry already has been making houses more energy-efficient over the years by paying more attention to foaming, caulking and weather stripping, and "passive" design pushes that another step.

"It's kind of been an evolution that's ongoing and 'passive' house is at the extreme of that," Davies said. "That's where you have a very specified amount of air that you need for good indoor quality and no more."

If this home performs as expected, Moon said Habitat could be building more "passive" design homes in the future.

The one being built for the Huante family in Bellingham has volunteer and financial support from local faith groups, according to Habitat.

Habitat for Humanity is a nonprofit Christian organization that builds houses for people of all faiths who need affordable housing.

Families help build their homes and then buy them with $500 down and a zero-percent interest mortgage.

Reach Kie Relyea at kie.relyea@bellinghamherald.com or call 360-715-2234.

ON THE WEB

? Habitat for Humanity in Whatcom County: hfhwhatcom.org.

? Passive House Institute: passivehouse.us.

Reach KIE RELYEA at kie.relyea@bellinghamherald.com or call 715-2234.