By Matthew Power Before it became an award-winning apartment complex, this steep hillside site in San Francisco seemed unbuildable. "It was the site of a massive landslide earlier in the [20th] century," notes architect Alex Seidel. "A couple of other designers took a crack at it and stubbed a toe. But we made it work by consolidating the parking garage for all of the units into one rectangular box and then incorporating the ascent of the hill into the design."
"The plan called for lifting the apartments in tiers, so they all have nice views," Seidel continues. "We also created courtyards and passages. Now there's a link between the local community and the Lone Mountain Campus of the University of San Francisco by way of a wide, stair-step passage through the center of the building."
Using a total of four acres, the project includes 136 apartments at an impressive density of 35 units per acre. Commercial features such as painted decorative metal and clay terra cotta roof tiles give the building rich textures that fit with older buildings nearby.
Hard costs averaged $192 per square foot, although the expensive site prep work was counterbalanced by the fact that the campus owned the land.
"We had to put the whole project on concrete piers," notes Seidel. "You had to test each hole, then pour to the right depth--up to about 30 feet in some cases. But ultimately, we were able to meet the engineering requirements."
Category: Apartments-rental; Entrant/Architect/Land planner: Seidel Holzman, San Francisco; Builder: Roberts-Obayashi, Danville, Calif.; Developer/Interior designer: University of San Francisco, San Francisco; Architect of Record: TWM Architects, San Rafael, Calif.; Landscape Architect: The Guzzardo Partnership, San Francisco
Stretching the Code
To keep the project within the four-story residential code (and thus more affordable), the architect cleverly used separation walls and varied entry points. "We had to work out six different residential levels, using wood framing that can only go up four levels," architect Alex Seidel explains. "So we stepped the structure up the hill and tailored it to the site. Any time you're working with high-density design, you have to address all design issues in advance--from courtyard size to whether you enter from the street or from a lobby."