Salon Summary: Walking the Talk at Choate


LEED, Net Zero

Plumbing magnate Herbert Kohler cast his bread upon the waters when he funded a LEED Platinum environmental center at his boarding school alma mater. Choate has made the most of this opportunity, building a combined dorm, dining hall, and laboratory that teaches about the environment in more ways than one. The audience at Urban Green’s sold-out When Buildings Teach got the inside scoop from the project team on October 3.

The Kohler Environmental Center is exemplary in its use of a low-cost, low-capital input approach adopted long before construction began. Choate sat down with the design team to carefully consider – and influence – occupant behavior and target comfort levels. When planning for a net-zero building, a single degree of extra summer cooling can mean tens of thousands of dollars of solar panels. Preventing this unneeded capital expenditure required long discussions about details normally considered too small for the architect, engineer, and energy modeler to get involved with. This included whether students could cope with 78F instead of 77F temperatures during the summer, how often faculty members would use clothes dryers in their apartments, and if students could reasonably be persuaded to forgo plasma TVs in favor of laptops.

Most building designs assume the worst of future occupants, and design HVAC, lighting, and electric services to match this dystopian (though perhaps realistic) consumption scenario. By setting more modest goals for occupant comfort, the designers were able to downsize equipment – and that meant fewer solar panels. While Choate benefits from knowing more about its future student and faculty “tenants” that a typical residential developer, the design team did two key replicable things:

  • Education. Choate teaches each student about how to use the green features of their building, including an energy dashboard that can compare the usage of individual dorm rooms. As the building owner and operator, the school has committed to deep tenant engagement about how to help their building perform sustainably – a big commitment given they’ll always have new teenage tenants every year.

Careful design. Orientation and window placement ensure that even laboratory areas can be operated without artificial light during daytime hours. Building massing minimizes cooling needs (there is a hope that in some summers, the AC will never be turned on). There are even buried concrete earth ducts to pre-temper conditioning air, precisely sized to reduced HVAC needs while avoiding mold-encouraging condensation.

The building incorporates some traditional (and expensive) green features – ground source heat pumps and acres of solar panels to serve the goal of a net zero building; high tech showerheads (more about those in a bit); and sugar maple wood paneling where you can see where holes were drilled for taps. More importantly, onsite Choate faculty member Joe Scanio is committed to seeing the 31,325 square foot facility meet its goals, semi-obsessively checking its 400+ sensors to ensure it is operating according to plan. By doing so, Scanio fills a common gap in green building – verifying environmental performance after occupancy.

Audience discussion was lively, possibly sparked by the presenters’ refreshing openness about challenges they faced during design. Emilie Hagen (Atelier Ten), Kevin Smith (RAMSA), Craig Razza (Kohler Ronan), and Scanio spoke of Choate’s ambivalence about building on a greenfield (in an area where farmland is scarce), before deciding that the academic benefits of doing so outweighed the environmental costs. I’m sure the student residents who watched from their windows as a hawk captured a rabbit would agree! Razza also brought up the challenges the team faced in maintaining a research-grade greenhouse without combustion; in the end, a biodiesel boiler was supplied.

But what about those high-tech showerheads? Funding from a fixture manufacturer has its distinct benefits. After polling design team members and client representatives about their shower habits, Herbert Kohler realized that while most people can live with a very low-flow showerhead, they do need occasional blasts of higher volume flow (for instance, to rinse thick hair). According to the panelists, Kohler directed his engineers to invent a new showerhead on the spot – in this case, a low flow unit with a high-flow override that can temporarily provide more water flow while a button is held down. They are installed and working at Choate, where users report satisfaction from the chance to briefly enjoy more water, while using it only a small fraction of the time. If these hit the market in the future, we’ll thank RAMSA, Atelier Ten, Kohler Ronan, and Choate for being willing to go outside the box in terms of tenant education and engagement.



About the author

Cecil Scheib
Cecil Scheib is Chief Program Officer for Urban Green Council.