Koji Tsutsui & Associates

House . Mill Valley

Koji Tsutsui & Associates . Photo: © Iwan Baan . + WAF

The Case Study House in Mill Valley sits on a site with steep slope at 40% (22 degrees) next to the San Francisco Bay Area national park.

On the first site visit, I saw deer, squirrels and wild cats and realized that there were a lot of wild animals although it is in a residential neighborhood. I thought this house should have a low impact on the wild life and natural environment by lifting up the house rahter than excavating it into the hillside. This is an experimental house, which is about a new collective form like a village that is sustainable and meets requirements of modern living.
The house is a composition of a cluster of wood frame boxes, which are rooms, the smallest functional and structural units. The boxes are elevated off of the ground on galvanized steel piloti, embedded in minimal concrete piers and grade beams, which reduces excavation, concrete usage and creep load on the foudation. The space between the floor underside and ground will be planted with native plants to stabilize the soil to prevent landslides during earthquakes and also free for the wild animals to roam around. The cascading flat roofs collect rainwater for the house water supply and also provide a water surface for wild birds to gather. The collected rainwater circulates the house as a grey water system for bathrooms, a drip system for landscaping or stored in an underground cistern.

The boxes are rotated at multiple angles so they overlap to connect spaces without any hallways and establish continuous loop circulations, which allow fluid movement throughout the house and allow interactions between inhabitants. At the same time, they are adjusted to views and solar orientation. Since the interior space has multiple angles and floor heights, you may not see the others, but can sense their presence.
The house is planned for an expansion in multiple phases from a single family dwelling to a multi-family housing. My goal is to make a microcosm of San Francisco where people of various cultural background learn to live together in this house. While each dwelling has its own living space, all dwellings are connected by Link Rooms where the inhabitants can share rooms to interact and learn from one another. Since the housing’s interlocking boxes create a cave-esque spatial experience, which blurs thresholds between the dwelling units and create a sense that they live together in a primitive village or community as one big family.
This case study house is made with an innovative method of construction where a human community is integrated into the ecosystem. The construction technology is readily available, which allows it to be built on any sites for a sustainable construction. It is not intended to be a finished architecture, but rather an opportunity and a start for a building that will always be in a process of growing and adapting to integrate the natural environment and modern ways of living.