Front Range architects encounter a recurring conundrum: Clients want large, west-facing windows to enjoy the stunning Rocky Mountains, but those very same facades expose buildings to the blistering afternoon sun.

Michael Moore, principal and founder of Denver-based architecture firm Tres Birds Workshop, was faced with this problem while designing Lumina, a new 61-unit apartment building set to open in LoHi this spring. When his firm sent off initial designs to an energy consultant, they discovered that much of the building’s energy load would be used for cooling—and it got the team thinking. “If we could shade the west and south sides in a way that didn’t make people feel like the blinds were closed, but in a way that we could cut out 50 percent of solar radiation, we could dramatically drop our energy usage,” Moore says.

It was the exact type of problem Moore wanted to solve when he started Tres Birds in 2000, after earning a graduate degree in architecture from the University of Colorado Denver. Today, as Moore adds more staff—now counting 21—Tres Birds tackles a variety of residential and commercial projects on the Front Range. Nearly all incorporate sustainable elements, whether that means opening up spaces to allow in more light or relying on alternative energy sources such as solar or geothermal.

To address Lumina’s energy problem, the team at Tres Birds got inventive. They created a system of movable, fabricated metal balcony screens; residents can slide the screens in front of the windows when the sun is at its hottest. An energy study showed that the revamped design would cut solar radiation in half. Beyond the savings, the screens also provide privacy from the street and are designed with a pattern that allows some light through, resulting in dappled shade inside the apartments. “The shadows they create,” says Moore, “make it feel like being under a tree on a sunny day”—nature’s original solar-shade blueprint.

—Photograph by Aaron Colussi; Rendering courtesy of Tres Birds