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We’ll Drink To This! An Über-Green Winery
Damion Hamilton photo
When you work close to the land, global climate change is not an abstraction but a tangible threat to your livelihood. And if you’re like the Duncan family, owners of Silver Oak Cellars, it might inspire you to take steps to heal and safeguard your imperiled ecosystem. Thornton Tomasetti’s Sustainability practice is working with the Duncans to achieve the highest level of certification available through the Living Building Challenge (LBC) for their 105-acre site in Healdsburg, California. Silver Oak is on track to become the first winery ever to receive this über-green certification.
Our relationship with the Duncans dates back to 2015, when we helped their Oakville, California, facility achieve LEED for Existing Buildings Platinum certification. The more stringent LBC standard employs a flower metaphor in which each petal represents one of seven performance areas in the LBC framework. The team is targeting Living Building Certification, which means that all seven petals must be completed. But the program allows for certification based on the completion of as few as three petals. Why take on the more difficult challenge of completing the entire flower?
The exceptional demands of these complex buildings inspired our team to go above and beyond conventional sustainability guidelines. We were challenged to think about how to not just take from, but give back to, the land, making the facility itself a steward of the environment.”
Achieving Regenerative Design
“From the very beginning, we set out to push the limits on sustainable building and innovative technologies for the Alexander Valley winery, and the Living Building Challenge aligned perfectly with this goal,” explained Haley Duncan, project manager at Silver Oak Cellars. “The requirements are arguably the most difficult of any green building certification, but the path to achieve them is more flexible. This allowed the design team to be more creative with their approach to each petal, and led us to invest in some truly cutting-edge solutions.”
The winery’s strong sustainability ethic was already evident in its organic wine-making and its Napa Green Winery certification. LBC is motivating the owners to pursue even higher levels of sustainability, going beyond reducing negative impacts to achieving net-positive results and the regeneration of living systems. For example, all water used must come from the site, and the treatment must return it to the site to continue the cycle. In this project, water for wine-making comes from on-site wells. Process wastewater is treated in the winery’s membrane bioreactor, then goes to the toilets, and eventually into the leach field.
The project entailed the construction of two buildings – the tasting room, which houses event spaces and offices, and the production and administration building – on a previously developed site. Together, their areas total more than 100,000 square feet. This is a large winery, with heavy process energy use. It incorporated at least 1,000 materials, each of which had to be vetted to meet the Red List Imperative to ban the most harmful chemicals. Material needs were very specific due to quality-control requirements in wine production and because the project area, which includes the vineyard, is so large. Hundreds of materials failed to make the cut.
The team evaluated the quantity of water (millions of gallons per year) entering and leaving the project boundary, depicted in this water cycle graphic, to meet the certification requirement that all water used must come from the site.
Lessons Learned
While LBC doesn’t always extend into operations, for this project, materials selection was tied to wine production. Vineyard irrigation involves considerable amounts of material, so we were challenged with finding low-toxicity alternatives to polyvinyl chloride. In addition, we had to find materials that wouldn’t corrode, affecting the wine quality. The reluctance of some manufacturers to disclose their products’ contents complicated materials selection. Effective vetting and documentation, as well as early meetings with the contractor, Cello & Maudru, helped us satisfy the materials petal requirements.
Each LBC petal comprises two or more imperatives that must be met to complete it. To complete the seven petals required for full certification, we opted for a two-phase audit, addressing the most challenging ones, including the materials petal, first.
Petals with the most imperatives tend to be more challenging, but some imperatives are more complex than others. The biophilic design imperative, which requires examples of designing with nature, cannot overlap the beauty imperative. However, many of the biophilic design elements – including a reflective water feature that flows alongside the glass exterior, and a staircase constructed of redwood salvaged from old wine tanks – are undeniably beautiful. In the end, a collection of modern bronze sculptures, distributed throughout the winery gardens, helped fulfill the beauty imperative.