20th Street ResidenceEdit profile
Our client came to us with a worn down home on Potrero Hill. The client’s main goal was gain more space – to achieve this it soon became evident that expanding up through the roof was our only way. This would not only meet their needs, but would take advantage of the view overlooking the Bernal Heights Park and San Francisco Bay. The existing 1575 sq. ft. became 2225 sq. ft. – and the sleeping and bathing would remain on the 2nd floor – while the public functions would rise to an addition on the roof.
One developer originally built the house and all facades on the block are identical. We were therefore not permitted to alter the existing façade other than replace windows and cladding due to the historic designation of the block. As the home faces south, the new dining and living space would be overly hot due to the large window opening and the need arose for a flexible sunscreen to provide protection from the sun. By perforating the skate-ramp clad sunscreen with a pixilated image of the street we combined the City Residential Design Guidelines, the shading strategy and the City’s wish to embrace the character of this block.
We chose to fully comply with all the zoning regulations, and let that be the solution to our design strategies. We maneuvered through many City issues, but managed to solve the project requirements within the mandated street front setback of 15 feet, extending 32 feet in height. The terraced garden in the back connects the more private and secluded 2nd floor to the living area on the 3rd level through a pathway of stairs and a new catwalk bridge. This allows the owners’ two dogs a free passage to the rear yard. For the interior we embraced the client’s love of raw construction materials. They especially wished for many visible and unpainted wooden surfaces combined with brightness and gloss. We recycled wooden roof joists and custom-built a shelving system. PSL beams were used for the stair connecting the old house to the new, and OSB sheets connected the 2nd floor to the entry.
To weave the house into the urban fabric the building was clad in the inexpensive Skatelite material, used to make skateboard ramps. This material, with its precision, makes the building autonomous and differentiates it from the neighboring houses – but simultaneously it enhances the original design by distilling down the primary elements of the original vernacular – in that sense the building once and for all reaches its full potential within the frame of the old style.
Sustainable Design is imperative for us. For this project we installed solar panels, and reused existing materials and minimized new materials to minimize waste. Our take on sustainability is foremost about the use of square footage. In every project – and maybe especially in this renovation and extension, every square foot has been thought through in its intention and objective. If we detect a spatial blind spot – we make sure it goes away or come to life.
Description from the architects