[ Page 6 of 6 ]

By Nancy B. Solomon, AIA

Austin Resource Center for the Homeless

Completed in April 2004, the 26,800-square-foot Austin Resource Center for the Homeless provides both temporary shelter and long-term support programs for the indigent on the site of a former gas station in the heart of Austin, Texas. The city-run facility, designed by the local firm LZT Architects, includes a double-height lobby, health clinic, laundry facilities, locker room, and computer room on the first floor; kitchen, dining room, meeting rooms, showers, sick room, and administrative offices on the second floor; and sleeping quarters, restrooms, and an outdoor terrace at the top. The building’s exposed structural system, a series of parallel concrete frames braced perpendicularly with concrete beams, affords spatial orientation, multiple visual connections, and abundant daylight—qualities that offer much-needed comfort, security, and hope to an underprivileged population.

During the predesign phase, Austin’s city council approved an ordinance requiring that the design of any new municipal building follow the guidelines developed by the U.S. Green Building Council for its LEED rating system. “We were very excited about that,” says project architect Murray Legge, AIA, “because it gave the client a set of helpful parameters.” It also gave the design team an opportunity to engage local environmental building consultant Gail Vittori of the Center for Maximum Potential Building Systems.

 

A 13,000-gallon rainwater-collection system helps to minimize local flooding concerns. Photography: © Thomas Mcconnell Photography

The team was particularly resourceful in their approach to material selection and water management. The structure, for example, relies on an innovative process dubbed “stack-cast tilt-frame.” Traditional cast-in-place concrete is expensive (because of the extensive amount of formwork required) and difficult to finish properly, so structural engineer David Powell of the local firm P.E. Structural Consultants proposed instead that the 12-inch-thick concrete frames be cast on the ground—one on top of the other like a stack of pancakes—with reusable forms, and then lifted into place with a crane. This approach allowed the contractor to easily and efficiently pour and agitate the concrete mix so that it would flow into all corners of the mold, resulting in a clean, attractive finish at a reasonable cost. Because the surface was of such high quality, the structural elements could remain exposed on both the exterior and interior, thus reducing the total amount of finishing materials required for the building. Overall, Legge was pleased with this construction technique, but he would prefer a larger area next time: “Staging was difficult because we had a tiny little site in which to lay the pieces out.”

To make the concrete assembly even more environmentally friendly, the architects requested that fly ash—a by-product of coal-fired electrical generation—be substituted for 45 percent of the portland cement, the production of which releases significant amounts of carbon dioxide into the atmosphere each year. Fly ash is stronger and, since free for the taking, less expensive than portland cement. It also provides a warm brownish tint. “But it’s tricky to work with because it takes longer to set up, forcing the contractor to sit out there and babysit,” notes Legge. It is also poorly suited to cold climates, which are subject to frequent freeze-thaw cycles.

Austin suffers from serious flooding problems because it lacks topsoil. To reduce the load on the city’s storm-water-management system, LZT developed a 13,000-gallon rainwater-collection system for landscape irrigation and for the flushing of toilets and urinals. Seeing both an architectural and educational opportunity embedded in this highly functional feature, the designers installed, like a row of sentries, eight 21-foot-tall, 24-inch-diameter galvanized-steel tubes within one of the structural frames just east of the front door. In keeping with resource-efficient practices, the water cisterns double as solar-shading devices in front of a south-facing window, creating a diffused, pearly light within the lobby.