In the last decade of the prefab homes movement, professional discourse and consumer expectations haven’t always been in sync. Despite a fairly extensive conversation within the design community weighing the economic and environmental pros and cons of prefabrication, many potential buyers have approached prefab simply thinking they can get a green dream on the cheap. “People are familiar with the modular home concept, so they think that prefab marries mobile-home technology and architectural significance,” says Lance O’Donnell, the founder of o2 Architecture in Palm Springs.
Courtesy NuVue Interactive
Lean, suntanned, and laid back, O’Donnell personifies his famous California address. And when David McAdam commissioned the architect to create a house in nearby Yucca Valley using a modular steel system, o2’s results were much like its principal. Half of the 1,000-square-foot rectilinear volume is multipurpose public space that links seamlessly to a cantilevered deck, and a factory-made mechanical core service both public and private sides of the interior.
McAdam and fellow entrepreneur Robert Brada then asked O’Donnell to transform the project, called Rock Reach House, into an offering of prefabs known as Blue Sky Homes. That catalog continued in the California vein, underscoring openness, indoor–outdoor connection, inspiration from local mid-century legends like Wexler and Frey, and lightest-possible footprints.
It was 2007, and while some potential homeowners like Gordon Graham worked with o2 to create a Blue Sky residence (this one measuring 1,225 square feet and also located in Yucca Valley), many others, upon grasping the full scope of land acquisition, utility connection, and other costs, backed off.
So McAdam and Brada shifted the course of their fledgling company, from marketing o2’s fully resolved domestic visions among homeowners to selling just the underlying structure to other architects. “Instead of a preassembled house, Blue Sky is more of a way to assemble a house. That’s basically where the margin is,” o2 architect Martin Brunner explains of the move. Today the design studio is one of 11 partner architects to which Blue Sky forwards customer inquiries.
Under the revised business model, Blue Sky still yields sustainability profits. Its construction package partly comprises bolted, bi-directional moment frames made from cold-formed, high-tensile galvanized and structural steel. Manufacturing facilities in Fontana and Wildomar, California, use steel with 70 percent recycled content and recycle almost all factory waste. Elements are prefabricated and ship flat for assembly on site.
The package also includes Pennsylvania-manufactured STEPs, or steel thermal efficient panels, in which expanded polystyrene greatly reduces the thermal bridging of light-gauge steel studs. “We looked at SIPs for our outer-wall solution but we ultimately selected STEPs as a better solution for our needs. There is no wood in STEPs and thus nothing to retain moisture and foster the growth of mold, unlike the OSB in SIPs. And STEPs provide locations that are ready for all MEP requirements—no cutting or drilling required,” McAdam says. STEPs are shipped to a job site very much like Blue Sky’s moment frames, and also are lightweight enough so that a person can put them together without heavy machinery.
In addition to its apparent material and construction efficiency, Blue Sky can be attractive to potential homeowners for reasons that are not necessarily green. For example, steel’s strength means long spans that can translate to extensive daylight penetration, and few limitations on configuring a residence more generally. “You can move the walls around; you can even take out all the interior partitions. You have this freedom,” Brunner says.
Freedom of choice also means that the burden of sustainability really falls on the architect and client, since, in this incarnation of Blue Sky, the project team alone is selecting a site, specifying glazing, choosing mechanical systems, and landscaping.
O’Donnell is keenly aware of this individualized responsibility. For example, he remarks that Blue Sky’s slim spread footings solve many problems of building in remote and sensitive sites—yet giving in to the temptation means extending the power grid and creating infrastructure that’s beefy enough for a fire truck rather than, say, a Volt.
That’s exactly the conundrum of an o2-designed house in design documentation in See Canyon, in San Luis Obispo, California, that employs Blue Sky construction. O’Donnell says of applying the system to the project’s ridge site, “Now there’s a way to go out there without really destroying the hilltop by carving out a pad. By moving pieces down a little road, you can achieve results that you couldn’t with a factory-made house.” To lessen some of the corollary impacts of the project, the house, which will be positioned to capture prevailing ocean breezes, will produce its own electricity and hot water.
Of another project on the boards, the Gilbert-Troost Residence in downtown Palm Springs, O’Donnell admits, “It’s when you get into this environment that it’s tough. In an extreme climate, you don’t see a dramatic energy-efficiency difference between this system and traditional construction.” Currently o2 is researching deep awnings, motorized shading, and other devices that can append to the structural frame to effectively create a second skin for the house. Just as there are many ways to reconcile the prefab movement with affordability, the Blue Sky case study demonstrates that, in matters of sustainability, one size does not fit all.