Against all odds this in-fill house in Dolores Heights is a well of light.

On a steep, hemmed-in lot in San Francisco’s Dolores Heights, a new four-story home by Dumican Mosey Architects transforms a once-derelict site into a light-filled, highly contextual infill residence. 

Though the 25-foot-wide parcel is typical for the city, its dramatic downslope—nearly 12 feet from front to back—and lack of side-yard exposure demanded a design that looked inward and outward simultaneously, relying on vertical space, framed views, and daylight from above.

The project originated as a speculative development on the site of a rundown 1920s-era house. As construction was about to begin, a couple with two young children purchased the property, drawn to both the Dolores Heights neighborhood and the architecture firm’s aesthetic. “They loved the design we had developed,” says architect Eric Dumican, FAIA. “They saw the opportunity to step in right as excavation and foundation work were happening and make it their own.” What followed was a rare evolution — from developer-driven project to fully customized 4,500-square-foot family home — allowing the architects to refine materials, detailing, and spatial programming throughout the four-year build.

From the street, the house reads as a three-story structure, carefully scaled to its surroundings and local height limits. Below, an excavated level adds living space without increasing the home’s apparent mass. “Four stories is fairly rare in San Francisco,” Dumican notes, “but because the site slopes down, it’s three stories above the street with one level tucked below.” That lower floor accommodates a media room beneath the garage, mechanical spaces, and bedrooms that open directly to the backyard.

The street-facing façade is composed as a series of stacked volumes clad in glass, steel, and striated limestone. Each level pushes or pulls slightly, creating depth, shadow, and movement along the steep block. “We wanted a sense of relief from the street,” Dumican explains. “These boxy geometries shift in and out, which helps break down the scale and gives the house a dynamic presence.” The limestone from SBI Building Materials is laid in a subtly irregular pattern—controlled yet seemingly random—to reinforce the home’s quiet material richness.

At the rear, where privacy is less of a concern, the architecture opens up. A full-height glass wall frames sweeping views toward downtown San Francisco, capturing landmarks like the Salesforce Tower and Transamerica Pyramid. Anchoring the backyard is a mature Monterey cypress—unprotected by code but deeply valued by the homeowners. The design gently terraces the yard around the tree, balancing canopy preservation with long-range sightlines.

Inside, the home’s organizing element is a dramatic triple-height atrium, positioned perpendicular to the façades. A folded steel stair slices through the volume, while a continuous blonde wood slat wall extends vertically across all four levels. Above, a large operable skylight draws daylight deep into the house and facilitates natural ventilation. “Because the lot is only 25 feet wide, we didn’t have side windows,” says Dumican. “So the opportunity was front, back, and straight up to the sky.”

Living spaces occupy the most transparent middle level, where terrazzo floors and sliding glass doors create a seamless connection to the deck and backyard, lending the room a treehouse-like feel enhanced by the cypress canopy. Throughout the house, a refined palette of Venetian plaster, wire-brushed oak flooring, and rift-cut millwork adds a tactile force.

For Dumican Mosey Architects, the project exemplifies a larger ambition. “We’re always interested in creating something timeless,” Dumican says. “Architecture that feels relevant today—but will still feel relevant many decades from now.”