Graham Northwest, Inc.

BOTHELL -- Builder David Stafford has taken a stand with his work -- a stand that allows him to walk barefoot on tile floors in winter.

Even on wet, windy and chilly winter days, the radiant floor heating system Stafford uses in his homes keeps tile and carpet a uniformly toasty temperature. And construction methods using insulating concrete forms help shelter the homes from drafts and traffic noise.

Comfort is one goal of Graham Northwest Construction Inc., Stafford's business, but energy efficiency is the main one, he said.

"I don't consider myself an environmentalist, but I'm in this to do more than just make a pile of money," Stafford said. "I feel that it's important for me to build in way that's better for the environment -- and for people."

Stafford has been building and marketing homes for 17 years, but his commitment to energy-efficient construction began four years ago. Most recently, Graham Northwest has built two craftsman-style homes off Fourth Avenue SE in north Bothell.

Both were constructed with exterior concrete forms, concrete floors and radiant floor heating. While there are other environmentally friendly building technologies, Stafford said he prefers the combination of steel-reinforced concrete construction and floor heating because they offer relative cost efficiency and design flexibility, along with structural durability, energy efficiency and comfort.

On average, insulating concrete form houses consume 43 percent less energy for heating and 32 percent less for cooling, according to the Portland Cement Association.

The method uses interlocking 2.5-inch Polystyrene forms to shape a special blend of steel-reinforced concrete into walls. Concrete fills the forms, covering reinforcing steel bars and leaving no air pockets in the 6-inch-thick slabs. The foam forms remain in place as insulation and as a hanging surface for drywall.

Not counting drywall and any finishes, the walls are 11 inches thick. That helps explain why the structures are more resistant to mold, infestation, extreme weather, fire and earthquakes, Stafford said.

Combined with the walls, the concrete floors create a solid thermal mass that helps insulate homes from heat and cold because the concrete is so slow to change temperature.

Radiant floor heating further helps reduce energy expenses. It works by circulating warm water through tubing buried in the floor.

"With a radiant system, you're not coming home to a cool house in the winter and waiting for the thermostat to kick in and catch up," said Paula Avery, marketing representative for Graham Northwest.

Energy Star-certified appliances, Low-E glass windows, efficient water heaters and extra attic insulation are also part of Graham Northwest's standard efficiency package, and all are included in the Bothell homes.

Low-E glass windows use thin, transparent coatings of silver or tin oxide to contain infrared heat inside the house, while still allowing outdoor light to shine inside.

Most of the features that make the new Graham Northwest homes distinct from their neighbors are hidden behind closet doors and inside the walls and floors.

"I could bring 10 people to look at this house, and unless they were looking for it, they might not ever know it's energy efficient," Avery said.

Indeed, the homes blend well into the quiet neighborhood and the greenbelt that runs through their backyards, and they offer many features considered desirable in today's new home market, including open floor plans, gourmet kitchens and spacious rooms.

That's in line with Stafford's original goal of creating homes that are both environmentally and buyer friendly. The carpets may be made of recycled soda bottles and the walls of concrete, but the prices are comparable to similar homes.

One of the two new Graham Northwest homes in Bothell is finished and on the market for $389,000, while the other is scheduled to be done in May.