Jan. 4--Santa Fe architect Mark Chalom and builder John DiJanni won the Su Casa magazine/Build Green New Mexico Award for Green Home of the Year and a Gold certification from Build Green New Mexico.

But according to Richard Bechtold, the owner of the award-winning house in the Eldorado area, they "just squeaked by" on the rating for the award.

Chalom, who worked closely with Bechtold and DiJanni on the design and construction of the home, said the rating systems used by Build Green New Mexico and the national LEED (Leadership in Energy and Environmental Design) certification apparently don't acknowledge the energy benefits of passive-solar design. The Bechtold house was designed to take full advantage of the sun with solar panels to heat water, and south-facing glass and trombe walls to heat the home.

A trombe wall is a specially designed and built structure that essentially "pumps" warmth into the house on winter nights. It is a thick wall of concrete or adobe -- "thermal mass" -- with a dark surface facing the sun and with an air space and glazing on the outside. During the day, the thermal mass slowly absorbs solar warmth, while the air space helps prevent its loss back through the glass, then the warmth is slowly released into the room at night.

In a similar but less efficient manner, south-facing windows maximize wintertime solar gain, the warmth absorbed by the thermal mass in concrete or brick floors. In the Bechtold house, this solar gain is accentuated by the fact that Chalom designed the interior walls to be constructed of heat-absorbing adobe.

Traditionally, the surface of a trombe wall facing the outside of the house has been painted black -- and DiJanni even had good results in the past simply finishing it with the darkest stucco he could find. On the Bechtold project, Chalom increased the efficiency of the trombe walls by applying a selective-surface film on the thermal mass.

"We've done trombe walls with adobe, which is 6,000 years old, and selective-surface film, which is space-age," Chalom said during a December visit to the house. "The film absorbs 95 percent of light that hits it, and only gives up 6 or 7 percent back out."

The bottom line on all of these strategies was to cut down energy consumption for heating in the wintertime. Bechtold said the team's main objective was energy-efficiency.

Chalom has long experience with energy-efficient design. "I used to work with William Lumpkins, who designed his first solar adobe home back in 1935," he said. "I lived in a geodesic dome when I came here in the 1970s. I'm a Bucky [the visionary architect and inventor Buckminster Fuller] freak.