Page 14 - GB Building Science Ebook 2019

Stormwater saver. Passive orientation.
Diverting rainwater into storage The long face of the rectangular
cisterns and eliminating impervious form is oriented to capture
surfaces keeps stormwater out of solar gain in the winter. Durable
Seattle’s sewer system. shell.
A baked-enamel
metal roof and
Allura fiber cement
siding make for a
low-maintenance
exterior.

FROM THE JUDGES

“Simple and powerfully

sustainable. Good
combination.”

the downstairs Airbnb apartment, without overflowing during the summer, while openings on the east and west façades are minimized,
rainy season. The system is also connected to the municipal water to prevent overheating.
system, so the cisterns will never run dry. The home’s design reduces heat and cooling load significantly. A
“This was kind of a first for Seattle, too,” says Clifton, adding that Chiltrix CX34 air-to-water heat pump supplies heating, cooling and
the city’s inspectors were eager to collaborate and get the system domestic hot water. A hydronic loop runs through the ground floor,
permitted. The captured rainwater and site strategies such as while ceiling-mounted fan-coil units provide heating and cooling for
permeable pavers also keep stormwater out of Seattle’s combined the second and third levels.
sewer system. Though new to the U.S. market, Clifton says the Chiltrix units are
relatively easy to install, not to mention five times as efficient as a
Low-Cost Luxury conventional tank-style water heater. The whole house is ventilated
TC Legend’s goal is to build only net-zero- and net-positive-energy by a Zehnder heat recovery ventilator (HRV) that scavenges 91
homes for between $200 and $250 per square foot in the Seattle percent of the heat from the exhaust air.
area (less in nearby Bellingham). Cost-cutting strategies start with Because of the link between natural gas and fracking, TC Legend
the site. The home is built into the slope, eliminating the need to doesn’t run propane appliances in their homes anymore. “The
import or export soil. The building is a 41.5-foot by 27-foot box, compelling argument for gas is gone,” says Clifton. Going all electric
oriented with the long side of the rectangle facing south. Strategically also eliminates an entire utility—another cost savings.
placed glazing maximizes daylighting and solar heat gain in the Other features that helped the home earn its Emerald Star

14 BUILDING SCIENCE SPECIAL REPORT: SIX WAYS CONSTRUCTION IS CHANGING