Lakeside renewal: in a Texas remodel, nothing goes to waste

Custom Home, July-August, 2005 by Meghan Drueding

In 2002 the owners of a 20-year-old saltbox in Austin, Texas, approached architect Robert Jackson with an interesting proposal. They wanted to remodel and enlarge their existing house on Lake Austin, a task that seemed straightforward enough. But they also wanted the project to treat the environment as gently as possible, an idea fight up Jackson's alley. For years his firm, Jackson McElhaney Architects, has quietly incorporated basic sustainable design principles-using regional materials, siting appropriately for the land and climate, and maximizing energy efficiency--into its work. "We're not heavy on promoting it as if it's some kind of unique thing," he says. "It's really a moral issue for us."

Jackson teamed up with veteran builder Carl Rieck of Austin's Radney Construction, who's built several green houses himself over the past few years. Together with the client, they came up with a plan to reuse as many materials from the original house as possible, and revamped the floor plan to encourage passive cooling and daylighting. And they helped a local rainwater collection expert set up a state-of-the-art, 25,000-gallon rain-harvesting system to serve as the home's main water supply.

The materials recycling strategy was something of a no-brainer. For every building component that gets a second lease on life rather than hitting the trash bin, a little more space opens up in a landfill. The clients also spend less money on new materials, though Rieck thinks the added labor required to salvage existing materials cancels out the cost savings. "It adds about 10 percent more time to a project, if you do a lot of advance planning," be says. His crew left the old house's walls and subfloors intact in as many places as possible. They saved and reused old rafters and structural members, as well as the air conditioning system and assorted items like a bathtub, a sink, and some mesquite cabinetry. Other existing elements reappeared in new locations--the original house's galvanized metal roof, for example, now tops several outbuildings, and some of the old masonry was incorporated into low stone walls on the property. Recycled materials from other sources weren't discounted either: All the upstairs flooring consists of tongue-and-groove teak from old freight train cars.

Low-maintenance finishes made up another essential part of Jackson's holistic green approach. "The exterior is stone and stucco, so the owners can just hose it down," he says. "They didn't want to use chemicals to clean it." Durable, sustainable engineered bamboo covers the downstairs floors, and low-VOC paints coat the walls. "This is the third house where I've used bamboo," says Rieck. "It seems to be very durable." Passive cooling and daylighting play key roles, too, but working them into the remodel was tricky, since local restrictions dictated that the new plan fit within the home's existing footprint. Jackson shifted rooms around, moving the entry and kitchen up to the second floor, where the home's major living spaces are. He pulled the home's rear wall out to encompass the former deck and second-floor porch, adding square footage without going outside the footprint. And he turned the old carport into a separate garage with an upstairs master bedroom suite, creating a dogtrot between it and the main house. "The dogtrot pushes the air between the two buildings," he says. "It reinforces the home's natural ventilation."

Carefully placed, operable windows on the second floor let in cooling breezes. "In Texas, cooling is more important than heating," says Jackson. "It's about understanding how the prevailing breezes work. During the hottest part of the year they're blowing mostly from the southeast, so you want to be sure you have operable windows on the south side. On the west side, you want to close things up and provide shade." Additional windows on the home's northeast corner capture prime lake views while still avoiding that hot western exposure. Downstairs, big sliding doors open up the two children's bedrooms and corner sitting room to the yard and pool, which form an outdoor room the clients can use all year round.

A pair of fiberglass rainwater tanks sits on the other side of the house, as unobtrusively as two 12,500-gallon tanks can. Rieck and his crew poured 4-foot-thick concrete pads to support the cisterns, which when filled weigh over 40 tons each. The water they store has traveled from covered gutters on the house's standing-seam metal roof through several different filters, which purify it to a desirable level for cooking, bathing, and even drinking. According to Jackson, the system will easily supply water for six to eight months for a family of four, even without additional rain. The facts bear him out--in the year-plus since the owners moved in, the tanks have never fallen below halfway full. (For more information on the water-collection system, see "Water World" this page.)

Jackson and Rieck are now in the midst of another green house collaboration. "In a good way, sustainable design is becoming a fad," says Jackson. "People are becoming aware of how limited our resources are. There are more sources out there for architects and designers so we can really accommodate clients. It's definitely the way things will go, sooner or later."--M.D.