A Tour of California's Caterpillar House

Rise recently sat down to talk with Feldman Architecture, the San Francisco-based architectural firm that designed the Caterpillar home located in the rolling hills of the Santa Lucia Preserve, about two hours south of the San Francisco Bay area. The modern-ranch home contains a strong connection between indoor and outdoor spaces, tied to the local landscape in a very tangible sense.

What Makes the Caterpillar House so Special?

Thermal Performance

The majority of the walls of the Caterpillar House are made from rammed earth, which was sourced from the soil excavated at the building site. According to the experts at Feldman Architecture: “At Caterpillar House, we chose rammed earth walls to act as these thermal masses. The walls themselves at 16” thick and are strategically located to capture heat around the building throughout the day. Obviously, they also provide a strong aesthetic that was used to define the material pallet of the home.  For this particular project, the entire team was drawn to the warm, natural color tones the walls provide.”

The home was designed for maximum solar heating and cooling through elongated East-West orientation that maximizes the efficiency of passive heating. The exposed concrete floors and rammed earth walls absorb heat from the daytime sun and release it slowly during the cool nights to naturally moderate the interior temperature of the building. In terms of energy-efficient windows, the South facing glazing has a U-factor of 0.25 and a Solar Heat Gain Coefficient (SHGC) of 0.4 to optimize passive solar gain.

Cross ventilation and ceiling fans throughout cool the entire home. Shading trellises and long overhangs on the south and west walls also reduce the need for a cooling system. Deciduous trees and retractable awnings provide summer shading on the south-facing glazing while allowing the sun’s heat to penetrate during cooler winter months. Air leakage is minimized with blown-in, bio-based insulation. The house also features an insulated, recirculating hot water system.

Energy Use Reduction

• A zoned radiant floor heating system is designed to reduce distribution loss and provides maximum comfort where it is needed most.
• Energy-efficient appliances and lighting reduce electricity consumption.
• An integrated photovoltaic panel system produces 115% of annual energy requirements (making it an energy positive home).

Feldman Architecture also recently signed onto the 2030 Challenge and the American Institute of Architects (AIA) 2030 Commitment, two programs that are promoting a vision that calls for all new buildings, developments, and renovations to be carbon-neutral by 2030. Stemming from these challenges and commitments, Feldman Architecture crafted its own Action Plan to serve as a roadmap to achieve these goals. The firm is committed to going beyond just sustainable design, including community outreach and office culture.

Bottom Line

Several architectural firms around the San Francisco area offer creative design services with a focus on maximum sustainability. The Caterpillar Home is a testament to how conscientious design can result in homes that maximize energy efficiency, reduce carbon emissions, and become a regenerative part of the landscape. And, the homeowner winds up with a healthier, more comfortable home that costs less to operate year after year.