Inside it's mostly one grand space; this colorful Tucson house is both budget-conscious and energy-wise

Sunset, March, 1991

Inside it's mostly one grand space Like a fire opal half-hidden in the Sonoran Desert, this simple house doesn't reveal its flashes of color until you are inside and catch its sparkling variegations.

Its clean, modern shell is just that> the house within stretches out--for the most part as one grand space--to the exterior frame. Interior walls are treated more like colorful sculpture, carved and shaped to define rooms and frame views. Because of the simplicity of the main stucco shell, it was possible to play with the interior space in this way and still keep construction costs about $60 a square foot for the roughly 3,000-square-foot house.

The 18- by 35-foot great room, above, is perfect for entertaining large groups> two staircases, and two corridors through the kitchen, improve circulation. An unkitchen-like sandstone counter serves as workspace and buffet between the kitchen andthe main room.

Despite two stories of glass facing the atrium, the house's interior isn't bothered by the sun. Window size, orientation, and overhangs were calculated to minimize penetration of summer sun and maximize that of winter sun. The green-pigmented concrete floor acts as a thermal mass> it absorbs sun in winter but stays shaded and cool in summer.

You see most of the house in the photographs here and on pages 124 and 125. What you don't see is the generous master suite past the far end of the balcony. Reached by the stairs from the front door, this private space, beyond the atrium, can be sealed off from thje main house with double doors.

Los Angeles architect Nir Buras designed the house, in Tucson, for his parents, Netty and Nathan Buras.