INDIGO ARCHITECTURE

The Indigo | Hammond & Playle Architects office is a Living Building Challenge certified Zero Net Energy commercial building in the heart of Davis California. The building is a unique example of bioregionally appropriate design principals applied for adaptive reuse and urban infill redevelopment. The building serves as an office, studio, gallery, and community space; and the design truly embodies the firm's mission to "integrate art, architecture, and ecology". The structure and furnishings utilize many local material resources such as agricultural biproducts and local hardwoods. Straw bale walls, crafted structural columns, and wood ceilings contrast with exposed services and corrugated metal finishes to create an honest blend of organic and industrial. The result is expressive and welcoming. Beautiful indoor spaces connect fluidly with comfortable outdoor courtyards that are shaded in the summer, and sunny in the winter. Additionally: natural ventilation, natural lighting, delightful views, and passive heating and cooling weave occupants into the fabric of their local environment.

The 4,000 ft2 all-electric building uses a small variable capacity air-to-water heat pump that cools and heats embedded surface radiant systems. Windows and skylights are motorized and automated to provide natural ventilation for cooling and indoor air quality. High efficiency ceiling fans allow occupants direct control over thermal comfort, while generous internal thermal mass, and embedded surface radiant systems provide exceptionally stable indoor temperatures.

Informed by building energy use simulations, and generative multi-objective optimization, we developed innovative mixed-mode control sequences to coordinate natural ventilation and radiant cooling so as to minimize energy use and shift electricity demand to off-peak periods. The sequence of operations is adaptive and predictive, yet simple enough to operate on a low-cost consumer-grade IoT automation system. We use weather forecasts, indoor and outdoor thermal measurements, and indoor and outdoor air quality measurements to choose when to open windows, and when to activate the heat pump. The adaptive algorithm automatically learns how to adjust temperature setpoints and schedules each day to maintain indoor thermal comfort throughout all seasons, maximize natural ventilation pre-cooling, and shift the time of electricity demand from mechanical systems. In addition to using natural ventilation for cooling, our sequence of operations includes a pioneering demand-controlled ventilation scheme that adjusts window opening to maintain indoor air quality.