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By Sara Hart

The design process was then driven by methods of restoration and reclamation in which the buildings assumed a supporting role. A flooded garden dominates the arrival zone. This garden is a demonstration habitat, which exhibits the characteristics of the naturally flooded delta that once dominated the area. Arbors, a native plant restoration nursery, a Texas Ebony shade garden, and several bird habitats are all part of the master plan to restore the area’s ecosystem.

With priorities focused on the land, the architects pursued forms and construction methods that tread lightly so as to do no harm and relate to the ad hoc architectural customs of the valley. Local farmers traditionally cluster buildings to create tree-shaded “comfort zones” for their houses. The visitors’ center is composed of three main structures, housing interpretive exhibits and multiuse space, administrative offices, a gift shop, and a café. The three structures are clustered in such a manner as to control shaded areas and garden spaces. They’re oriented on an east-west axis, parallel to an irrigation canal on the south, in order to capture the prevailing summer breezes. The buildings face south, east, and west to block the summer sun; on the northern side, vision glass provides views into courtyards and vistas beyond.

 

click images to view them larger 1 2 3 4 The sophisticated building envelope at the University of Texas Nursing School/Student Center is tuned to respond to the climatic conditions of Houston, from the percentage of glazing used on each facade to the design of shading devices. The glazing is spectrally selective with a low-E coating and a low-U value. Users have control of the thermal environment through operable windows and adjustable airflow controls. Drawing: Courtesy Lake/Flato

The exterior clay-block walls made in D’Harris, Texas, provide a highly efficient thermal mass, but they also lend color and texture to the surface. The blocks slow heat gain during high-gain periods and release heat at night. Behind the wall is a deep airspace and radiant barrier to repel additional heat gain before the heat reaches the R-19 insulated wall cavity.

The deeply corrugated, barrel-vaulted roof spans a long distance with less material and eliminates structural redundancies. As compared to traditional truss and deck steel, this system reduces the amount of steel required by 48 percent. However, it serves a critical architectural purpose, as well. “The vaults of arch-panel shell roof are a reaction to a prominent form in the agricultural vernacular of the area,” explains principal Robert Harris, AIA. “These practical and efficient shell structures are commonly used for economical barn and storage structures.”

“Engineered wood framing was used on the Hawk Tower and viewing blinds for several reasons,” explains Harris. “First, it has a more natural feel in a remote habitat area; secondly, it eliminates the potential for unchecked rust. It’s an efficient use of wood products to choose engineered material rather than solid stock in larger sizes.” Engineered wood has become popular as a substitute for the decreasing supply of old-growth trees. The wood comes from plentiful species, such as aspen and poplar, which typically is engineered into laminated strand lumber (LSL) and treated with a noncontaminant preservative called ACQ, a combination of copper and quaternary ammonium compound dissolved in an alkaline carrier system.

There aren’t many projects that call on architects to heal the land while they’re fulfilling program requirements, so in some ways, the World Birding Center is an extreme example. On the other hand, it’s a textbook case of the invisible process that creates architectural form with meaning that is transparent and comprehensible. Projects such as Lake/Flato’s Nursing School/Student Center building at the University of Texas Health Science Center in Houston are more the norm. The university’s administration mandated that the school be a model of sustainable design, believing that a building that houses health and wellness programs ought to be healthy itself.

As with the Birding Center, the final result is more than the accumulation of high-performance materials and low-energy systems. But unlike the center, the $57 million nursing school had a complex program, one driven as much by the status a well-designed, state-of-the-art facility brings to an educational institution as by its mandate to be a model of sustainability. Lake/Flato and the Houston office of BNIM Architects collaborated on the school and achieved that coveted LEED Gold rating with all the familiar features. The design incorporates low-embodied energy (made of materials that require less total energy to extract, manufacture, transport, construct, maintain, and discard), local materials, daylighting, 60 percent reduced building water consumption, and natural gray/black water treatment systems. Its sophisticated envelope is tuned to respond to the climatic conditions of Houston, including operable windows and spectrally selective glazing.

Principal Greg Papay, AIA, explains the process by describing the final product. “In the end, highly sustainable building does much to emulate nature and natural systems. While it’s easy to tell the visual difference between a branch and a leaf, just as it is between, say, a facade and the structural system, the two by necessity are highly integrated, each supporting a larger whole, each other, and the subsystems within their components,” he explains. “In essence, there is a continuum and an interdependence. So the best way for the process to produce that product is for the process to share the same approach.”

In his book, Fernandez warns against the temptation to “distill an essential meaning from the materials themselves.” The warning applies to the assignation of value to architectural form simply because it’s infused with quantifiable sustainable features. Lake/Flato’s process prevents its work from falling into this trap. The firm appears to adhere to Fernandez’s dictum that “it is in a material’s use that value is struck and intention fulfilled—that is, transformation toward meaning from lowly material to humane building is achieved through the action of deep values.”