We were approached by the owner of this property to convert an existing single-family residence into a three-unit building. This required that we add two stories above and one story below the existing structure. The extensiveness of this structural intervention allowed us to create three units that were each different in size and program. Although each unit had a different character based on scale and relationship to natural daylight, we used the material palette to stitch the three units together into one cohesive building.
The project is situated in a dense urban condition, adjacent to multi-family buildings. The massing of the project mediates between the disparate forms of the two adjacent structures, but takes on a character of its own with a composition of windows based on the interior spaces’ relationship to the street below. Privacy is given to the bedrooms directly above the street level by minimizing the window sizes and creating walls of dark cement plaster. Expansive panes of glass are provided on the upper floors as visual privacy from the street becomes less of a concern. As a result, the materiality of the building is visually heavier at the base of the building compared to the lightness of the upper levels.
Maximum emphasis was placed on harnessing natural daylight and providing cross ventilation within each unit to minimize energy consumption. A hydronic radiant system is employed in each unit, but no cooling systems are provided. The cross ventilation strategy is especially effective at this site on warm days since it’s located on the leeward side of Twin Peaks. The breeze/wind comes over the hill and down onto the site regularly over the course of the year, allowing the house to take advantage of this unique and natural San Francisco cooling condition.
The front elevation is a composition of steel frames with aluminum windows and integrally colored cement plaster infilling the steel framework. The amount of glazing increases at the upper levels as privacy from the street below becomes less of a concern. Sheer curtains, walnut wood veneer, and travertine floor tiles at the interior spaces add layers of warmth as a counterpoint to the taught overall design. Even though these interior materials are used consistently throughout the building, each of the three units has its own character. The lower unit is defined by a double-height volume that opens onto a minimal rear yard. The middle unit contains a central walnut bench/bookcase that serves to mediate the floor level change between the kitchen and the living room. The upper unit features a primary suite with an abundance of glazing that is perched above the living room and kitchen. Each of these residences creates a unique experience for absorbing the view of the city beyond.
We wanted to express transparency vertically rather than horizontally, with the San Francisco city view as our focus. Inside, we focused on natural elements that would age with time; walnut cabinetry, travertine floors, blackened steel and stone tile. All materials were used similarly in the three homes to give a larger sense of cohesiveness. In the end, the collaboration with the architect proved to be a true meeting of the minds, resulting in a lasting friendship.
Michael Hennessey Architecture is a San Francisco-based boutique architecture and design studio pursuing an architecture that inspires. Our practice is driven by a commitment to working with natural light and materials to create simple yet striking backdrops for everyday life; we approach design with analytical clarity and a commitment to embracing each site’s specific climatic and environmental conditions. We see architecture as central to a client’s life, and aim to transform their aspirations into sensitively-built material form.
Founded in 2009, Michael Hennessey Architecture has been nationally and internationally recognized for our ability to fuse the historical with contemporary while maintaining a direct and straightforward material palette. Our projects range from custom furniture to ground-up multi-family residential buildings, and exist in both urban and rural settings. Founder Michael Hennessey earned his degree from UC Berkeley and is licensed in the state of California.