Hailing from Brussels and Tapei, Bercy Chen Studio principals Thomas Bercy and Calvin Chen founded their design office in Austin in 2001, not long after graduating from the University of Texas at Austin. Despite—or, arguably, because of—the partners’ relatively recent Stateside arrival, their work is particularly attuned to place. Bercy says, “We always discuss the particular nature of every site we work on; Central Texas has an amazing geology, as it’s located between clay deposited by the Gulf of Mexico and a limestone–granite plateau to the west.” A recently completed project called Cascading Creek House embodies the studio’s consideration of modern forms, active sustainable technology, and the natural world as one.
Photo © Dan Bernstein
This large house is designed for a young family that had already purchased two acres of Texas Hill Country on the edge of Austin. Bercy adds, “The husband is extremely versed in sustainable technologies and anything related to home automation. He was very interested in including as many green features as possible.”
Typical of hill country, the site is exposed limestone topped in clay and soil in places. The composition makes for a stable foundation, but it largely repels water in the downpours that befall this part of Texas. Also of note: there is a 30-foot grade change on the Cascading Creek property. Limestone’s imperviousness explains regional erosion patterns like sinkholes, Bercy says, so the design team drew inspiration for this sloping site from the vernal pools in nearby outcroppings.
“To remedy the runoff situation we created several structures within the landscaping that divert water to a 30,000-gallon collection tank, which can provide irrigation for two months of drought,” Bercy says. A bypass channel moves excess water to the gully below, as well. Runoff especially drives Bercy Chen’s architectural gestures, and in particular the placement of water elements at the entry of the house, where its two wings intersect in a skewed V shape (the footprint was determined by the presence of three mature oak trees). By using a cantilevered plane and an oculus to funnel water into these decorative accents, Cascading Creek House behaves like a limestone outcropping to its vernal pools—and appears as such, since the house is nestled into its downward-sloping hill. “We love to take something quite utilitarian like a water collection system and give it a more poetic connotation.”
Functionally, the roof also behaves like a reservoir, as Bercy puts it. The standing-seam surface collects sunshine: A 5-kilowatt photovoltaic array covers approximately 400 square feet of surface, and 21 glazed solar thermal panels take up another 560 square feet and generate about 124,264 BTUs per hour. Another swath of rooftop is planted with native flora. Bercy Chen currently is working with the Lady Bird Johnson Wildflower Center to improve market conditions for these hanging native gardens.
The architect also orchestrated natural resources. Most notable, in order to control interior climate and produce hot water, a hydronic heat pump is integrated with the glazed solar thermal panels as well as phase-change material and a swimming pool for thermal energy storage. The decorative water elements work in tandem with the swimming pool as a heat sink and source to replace geothermal ground loops and maximize energy efficiency.
An Apple interface puts these tightly interwoven systems at the husband’s fingertips, and Bercy reports that performance readings thus far are very optimistic. He observes, too, that the interface is easy for anyone to grasp, saying, “We hope that this project inspires others to think about sustainability in a holistic manner instead of as disconnected sustainable features.”