Trestle Residence

2024 Residential Design Award Citation Recipient

Nestled on a Northern California hillside, this private residence negotiates a complex undulating site with sensitivity and earnestness. Structures are arranged to exploit the site’s diversity of views, foliage, and topography.

The design embodies the agrarian character of an active farm, reflecting its owners’ sensibility and ethos. Approached through a winding shaded drive, the home presents itself modestly amongst heritage oaks and a steep wooded hillside. The home is composed of a series of indoor and covered outdoor spaces, each with a distinct relationship to the surrounding landscape.

Structures are composed of local fieldstone, concrete, and steel, enabling a reciprocal relationship to the natural terrain and working farm.The home’s arrangement enables passive ventilation through expansive openings and stack effect through a long clerestory. Solar energy is harnessed through a solar PV system and a hydronic system for pool and domestic water heating. A large-scale water collection system provides water for agricultural irrigation, fire mitigation, and domestic use.

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A beautiful, wonderfully detailed, single family residential project, with a very nice connection to the site, that generates spacial quality from an otherwise flat plan while integrating passive sustainable features.

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Measure 1: Design for Integration

Sited in an area with a recent history of wildfires, the design was conceived with great awareness towards sustainability and longevity. On a macro level, the residence is built on the pads of previous structures to minimize disruption to the landscape, and as such negotiates complex shifts in existing grade. In addition to meeting fire-safe standards for building assemblies, the home is equipped with an external sprinkler system and surrounded by drought-tolerant planting. A large-scale water collection system provides water for agricultural irrigation, fire mitigation, and domestic use.

The residence itself embraces biophilic design to maximize the occupants’ comfort and connectivity to nature. It utilizes the thermal mass of stone and concrete to buffer against extreme heat, and high-performance glazing to maximize daylight and frame views of the surrounding landscape. Indoor air quality, and the ability to passively cool the home, is controlled with operable glazing leading to exterior decks and terraces. During periods of extreme heat or poor air quality, the home is mechanically cooled using energy from the rooftop solar PV array.

Measure 2: Design for Equitable Communities

In the aftermath of the 2020 wildfires that ravaged this and other properties in the area, the clients worked with the local Fire Department to establish firesafe features for the community. This includes determining dedicated lookout points on their property, and cooperative egress networks for remote parcels to serve the surrounding neighbors’ homes and to protect the area’s verdant landscape.

Measure 3: Design for Ecosystems

During the 2020 wildfire season, multiple trees on site were destroyed and slopes were in danger of erosion. The hillside has since been seeded and additional drought-tolerant plantings added, a strategy which was proven successful in the storms of late 2022 and early 2023. To support regional habitat restoration, native meadow grasses were seeded throughout the property, and additional native oaks were planted. Additionally, pollinators are utilized to virtually eliminate the use of pesticides for agricultural purposes. A symbiotic relationship between building and this landscape was fundamental to the design.

Measure 4: Design for Water

Both water conservation and collection were considered. The project’s approach to water conservation begins with drought-tolerant planting on the property. Irrigation for agriculture on the property relies on well water treated on-site, allowing for the farm to be self-sufficient. Large concrete water tanks on the property collect and store water for domestic use, irrigation and fire mitigation.

Measure 5: Design for Economy

Careful consideration was given to the strategic use of finishes as relates to cost and occupants’ psychology. A rustic palette of materials comes together in the main living spaces — board formed concrete walls, resawn cedar ceilings, and distressed oak flooring — to offset a refined composition of furnishings. Composed of painted walls and concrete floors, finishes in secondary spaces are more subdued while in dialogue with the main palette. The project was constructed on a fast-tracked schedule for efficiency in overlapping trades and costs. High quality, low maintenance finishes improve the home’s longevity by minimizing costly upkeep.

Measure 6: Design for Energy

Orientation and material selection predominantly drive the massing of this home. A west facing entry juxtaposes a heavy stone wall with dark wood siding. Main living spaces are characterized by large expanses of operable, high-performance glazing under deep overhangs, allowing for northerly views and daylight while mitigating solar heat gain from the south. The home’s arrangement of single-loaded spaces facilitates passive ventilation through openings, and stack effect through a long clerestory in the primary living space.

Measure 7: Design for Well-Being

Conventionally, buildings in the region work hard to offset solar heat gain. However, early daylighting studies revealed that this building site, backing onto a steep hillside, requires an additional strategy to bring in ambient light in the winter months. As such, considerations for wellness are embedded in the planning of a large south-facing courtyard, allowing daylight to penetrate into multiple living spaces. In the summer months, covered outdoor spaces allow occupants to gather and take advantage of the indoor-outdoor lifestyle afforded by the site. Interior shades sense solar heat gain and lower or raise automatically.

Measure 8: Design for Resources

Materials in this home, some reclaimed, were selected to weather with their natural surroundings. Locally quarried stone was used for the monolithic entry wall. Board formed concrete walls were untouched to express the local stone aggregate colors. In the courtyard, solid wood benches were carved from locally sourced fallen Douglas Fir. Throughout the interiors, reused materials were sought for customization —reclaimed oak shelving in the family room, and a reclaimed teak countertop in the powder room. Locally sourced materials not only reduced the carbon footprint of construction, but express a local working farm’s spirit.

Measure 9: Design for Change

One major event anticipated in building in this location is wildfire. Thus, the clients worked extensively with the county to designate fire-safe measures on the property, such as creating multiple access points and fire lookouts for the community. For the design team, creating a fire-resistant structure meant specifying fire-rated materials and assemblies, and designing defensible space into the landscape and hardscape around the home. Blackouts are anticipated with a generator on-site. Most spaces are planned on a single level within the residence, and additional provisions are in place to allow for its use as a multi-generational home.

Measure 10: Design for Discovery

A journey through this residence unlocks views and emotions connected with the site. This property is unique in its multitude of elevation changes within the building footprint, as well as dramatic shifts in views and flora based on orientation.

As evidenced by the pandemic, the home became a haven for the clients to live and work productively during a shift in our lived reality. Spaces created to enable the simple acts of contemplation, cooking, eating, and gathering, became pivotal to providing a joyful connection to nature and to each other.