The 100K Houses were conceived as a response to the currently unsustainable approach to housing. Small, efficient, and super-green, the 100K Houses provide sustainable, affordable options for first- time Philadelphia homebuyers. Rather than start with stylistic concerns, we began by asking how housing could behave more like other consumer goods, competing for the attention of buyers not only through visual appeal, but also metrics, critical performance criteria, and word-of-mouth marketing. Acting more like industrial designers than architects, we distilled the house to its spatial essence – a clean box with few walls, one bathroom, and an open layout. We designed from the inside out, articulating systems, utility cores, materials, and details as crucial drivers of our design strategy that are reflected in a straightforward manner on the exterior. The 100K Houses deploy good design to markets lacking access to professional design services by providing design based in local lifestyles, and offering consumer choice through an on-line shopping site where people can experiment with custom configurations as they would when buying a car or a laptop. Green technologies employed across all of the houses include photovoltaic panels, solar thermal hot water, radiant floor, ERVs, and mini split ductless systems. Experimenting with pattern, texture, and color, we employed super flat material variations in fiber cement cladding on the 100K House facades. Certain designs included silkscreen printing on the panels prior to installation. Interior finishes include plywood, OSB, exposed concrete, and bamboo hardwood.