Green Is… Adaptable

The challenge: Combine the style of an architect-designed home with the sustainability and economy of a prefabricated structure

High on a rise in Texas Hill Country, a family’s contemporary ranch retreat presides over the rugged, rolling landscape. Its design and layout, custom-tailored to the site by architecture firm Lake|Flato, powerfully evoke the area’s ranching heritage. Although sleek and modern within, the two single-room-wide structures recall rustic cabins. Their roofs and exterior walls are covered in galvanized corrugated metal, while slatted-wood enclosures resembling barn doors form porches and a separate carport. Recycled concrete pathways that link the structures wind around undisturbed stands of trees.

For all its sense of place, this compound was not designed exclusively for this site or these particular clients. Instead, it is composed of pre-designed modular rooms built completely in a factory and then trucked to and assembled at the ranch site. The structures were meticulously positioned in their preplanned configuration to capture the views while maximizing passive cooling and heating. The longer building contains a living/dining/cooking area linked via a breezeway to a master suite, and the smaller one contains two bedrooms and a shared bath for the owners’ twin teenage daughters. Finishing touches including porches, a breezeway and a carport were custom built on-site in the local vernacular.

It’s a revolutionary approach to residential construction, combining the style and flair of architect-designed homes with the sustainability and economy of structures prefabricated to LEED-certification standards. Yet the Porch House—as the system has come to be called for its unique site-built elements—has evolved naturally from the long experience of the firm that created it.

Founded in 1984, San Antonio-based Lake|Flato first gained a business toehold by creating “pretty modest second homes in the country, where our clients could celebrate the outdoors,” says cofounder and principal Ted Flato. “We originally designed houses in such a way that style took a backseat to fostering cross-ventilation and outdoor living.”

A quarter-century later, the firm had grown into a multi-faceted practice of more than 50 staffers, including a full-time “sustainability coordinator,” and with residential assignments involving far larger and more elaborate homes. Flato and his colleagues began thinking about how they might “get back to having great architecture that more people could enjoy for a reasonable price,” in the words of the firm’s associate partner Bill Aylor, a driving force behind the Porch House concept.

Although the Porch House concept has found some of its first expressions in areas not too far from the Lake|Flato headquarters, Flato sees the approach as adaptable to a wide variety of settings and uses. The individual prefabricated room modules can be customized with a range of finish options and then combined and configured in any number of ways. The built-on-site porch elements serve as what the firm describes as a “connective tissue” that ties each home to its setting.

By way of example, Flato cites a new Porch House project underway in the Rocky Mountain town of Lake City, Colorado, where the modules are being stacked and equipped with an internal stairway to create two-story, two-bedroom homes. “Add a wood-burning stove downstairs that carries heat upwards, spray-foam wall insulation and low-E windows,” says Flato, “and these Porch Houses can be practical year-round homes that make a lot of sense in colder climates.”

Regardless of the intended setting, the Porch House fulfills a basic goal Ted Flato and his colleagues set for the project from the start. “This was an effort to get back to something simpler,” he says, “to have great architecture that more people could share and enjoy.”



Architect Ted Flato answers key questions about the Porch House concept.

What makes a Porch House smart and sustainable?
“There’s very little waste when you build offsite in a factory because you can recycle materials and the people who work on the project are not traveling very far. The entire building process has a smaller carbon footprint. We build each Porch House with the best insulation, window systems, air-conditioning and heating, and with great cross-ventilation. And we orient each structure on the site and add overhangs, awnings, porches, breezeways and other custom elements to make it as
energy efficient as possible.”

How much energy does a Porch House use compared to a conventional home?
“While it’s hard to give an exact number, the Porch House modules and the site-built elements we add to them are all designed to use considerably less energy than typical houses. If you add photovoltaic panels to the roof and make other specific energy-conservation choices in the
construction and siting, it is possible to have a net-zero-energy-consumption house.”

How long does it take to design and build a Porch House?
“The design process usually takes one to two months. After you decide you want a Porch House, we walk your site together, discussing how many rooms you want and how they’d be configured. Then you would come back to our office to pick materials and see how it all lays out. During the next six to nine months, permits would be obtained at the same time the rooms are constructed in the factory. The site would be prepared, the rooms would be delivered and all the site-built elements would be added.”

What does it cost?
“From the very beginning of a project, we’re always talking budget. Apart from the site itself, our current projects range from about $150 to $225 per square foot. The price depends on the different design choices you make in terms of interior and exterior finishes, cabinetry, fixtures, fittings and configurations of the modules. When you come to our office to make all those decisions, you can see how the tab is running up and change your material choices if necessary.”


ARCHITECTURE Ted Flato, Lake|Flato Architects, San Antonio, TX, 210-227-3335,; to find out more about the Porch House concept, visit

Categories: Cabins