While the homeowners' choice to build their new ultra-insulated passive house on an urban infill lot made sense on many levels, it also led to some major challenges. A massive basalt outcrop dominated the site, resulting in the lot remaining vacant for decades as the neighborhood grew around it. The architect sited the home on top of the outcrop with retaining walls around the home to create a flat plane to build on. Even pushing the limits this way resulted in limited outdoor space, but the intimate courtyard areas provide make the most of what's available. The natural basalt retaining walls create a sheer drop along one side of the house, so decorative metal screens alternate with vertical continuations of the basalt wall.