STYLE: ARCHITECTURE : Angles of Repose : Hard edges in three homes are softened by blendings of concrete and wood : Simple Pleasures

Early in this century, architect Irving Gill discovered that if he stripped decoration from the walls of Spanish Colonial houses and simplified the floor plan, an architecture of pure form and abstraction resulted. The line between hacienda architecture and Modernism was thin, and he erased it.

Paul Lubowicki and Susan Lanier, two young architects with a practice in El Segundo, recently reiterated the discovery in a 1,300-square-foot bedroom-and-gallery addition at the back of a sleepy Spanish revival house in Brentwood. From the front, the two-story, L-shaped home, designed by 1920s traditionalist John Byers, is a Romantic classic worthy of a Ramona pageant, with an oak balcony overlooking a walled entry court. At the rear, the simple and serene Modernist addition grows out of the old house as if by Darwinian evolution, the plain new walls emerging from those from 1925.

Before hiring the architects, the owner of the house, Susan Stringfellow--an interior designer and associate at the Angles gallery in Santa Monica--had already created a Minimalist interior that echoed the rudiments of old Spanish farmhouses in its aesthetic austerity. She had painted walls inside and out white to contrast with the dark, stained wood trim. She had bleached the floor, and in the emptiness placed a few good pieces of country furniture, the natural woods waxed with a dark stain.

Stringfellow wanted the addition to have the same spirit. “I wanted harmony between old and new, but I didn’t want the new to imitate the old: that would be Disneyland,” she says. “To bring about the harmony, we worked to keep the addition from overwhelming the old house, and we used materials with a sense of authenticity. I’m passionate about steel and concrete. It’s somehow rewarding to use things that aren’t easy but are beautiful when finished.”

Lubowicki and Lanier designed an L-shaped addition that mirrors the configuration of the original house. Alongside the existing living room, they paired the new gallery, doubling the living area, and then extended the bedroom wing back into the yard.

Working with Stringfellow, the architects emphasized the character of the materials, as in the serene gray-green limestone floors and the luminous honey-colored, vertical-grain Douglas fir doors. A long, poured-in-place concrete wall retains a swirling grain imprinted by the board forms of the mold; the unpainted plaster walls inside have the translucency of skin, revealing variations in color and depth. Stringfellow allows the materials and spaces to breathe by furnishing the rooms with the same simplicity as in the original house.

Unlike Byers (and even Gill), Lubowicki and Lanier did not think of the addition as a grouping of boxlike rooms but broke it into parts that they telescoped into the yard. At the garden end of the bedroom, a small sitting room projects into the garden, brushed by lavender, and at its end, an elegantly blunt and square concrete fireplace projects even farther, engaging a narrow reflecting pool.

Light washes all the surfaces through clerestory and side windows as forms slip by each other allowing views outside--especially in the large shower stall, where white free-standing walls devoid of tile face a plate-glass view of a side garden. Meanwhile, a thick beam runs the length of the interior, uniting the different spaces and collage of materials. “It’s a traditional gabled house with all the elements expressed,” says Lanier. “We don’t like things that look over-designed.”

In the artistic circles in which Stringfellow works and socializes, light has been a subject and medium of particular interest since the time when artists of the 1960s went beyond painting to use it to create atmospheric effects. Similarly, Lubowicki and Lanier bring light inside to create sun paintings that shift by the hour. By breaking the bedroom addition into its architectural parts, placing windows in spaces that would normally be corners, the designers not only open the addition to the garden. They also create interiors that are catchments of light, in which change is the order of the day and serenity the revelation.