E. Cobb Architects Partners’ eHAB project is a self-sustainable, habitable structure built to endure extreme environments—a conceptual idea turned real.
Photograph by Michael Cole
Founder Eric Cobb and his team conceived of eHAB during the economic downturn of the late 2000s. At the time, the studio was working on projects across the country, each with distinct and specific environmental challenges: meeting seismic stability requirements, solutions for high-wind zones, and structural integrity to withstand heavy snow loads. Cobb saw a common thread—the need for steel framing—and wondered: What if there was a prefabricated, compact, self-sufficient, and durable structure that could withstand nature’s harshest conditions, all while being adaptable to various environments?
This raised several key questions: How do you build to last, avoiding the limitations of typical residential wood structures? How could the prefab method be used to improve quality, not just speed and cost? And how could the robust structure itself contribute to the dwelling’s overall character?
In 2010, a client contracted E. Cobb Architects Partners for a primary dwelling on the northwestern shore of Lake Washington. As the main home design took shape, the client requested a sheltered structure to function as an Accessory Dwelling Unit (ADU) and home office—near the water, at the base of a steep 60-foot embankment. Due to difficult land access, traditional construction would be prohibitively expensive. Cobb proposed their conceptual prefab project, which could be pre-built and floated by barge to the site.
The client was enthusiastic!
Photograph courtesy of E. Cobb Architects Partners
Cobb turned to Dogwood Industries, a Sedro-Woolley company specializing in steel structures, and they eagerly accepted the challenge. After Dogwood completed the basic “box,” Cobb had specialty subcontractors customize the interior with a stainless steel kitchenette, IPE wood bathroom cabinetry, a Murphy bed, and other touches that aligned with the firm’s custom residential work. (While eHAB was conceptualized as self-sufficient, capable of integrating energy-generating systems, this installation had access to utilities and did not require a composting toilet, solar panels, or other off-grid elements.)
The 30’ x 16’ core prefab structure is 100% steel and weighs 35,000 pounds. 92% of all steel is recycled; eHAB’s steel equals about 14 recycled cars. The completed structure was rolled out of the Dogwood factory on a temporary platform, loaded onto a flatbed truck for a 2-hour, 70-mile journey to Lake Washington, then placed on a barge and floated half a mile to its final site. There, it was craned ashore and moved atop a foundation box and two columns. The foundation serves as a utility and storage area, while the open space below is a covered outdoor kitchen and patio.
Photograph by Michael Cole
Though the core structure’s ceiling provides waterproofing and insulation (useful for transit), an additional steel roof—assembled on-site—catches 99% of weather exposure. Outriggers, also reattached on-site, enable deep eaves for shade and shelter. An IPE viewing deck, built on the extending steel beams, provides outdoor living space. The exterior stair is designed to accommodate up to a 30-inch height variation, much like a jetway stair, with a rotating attachment detail at its top.
Photograph by Michael Cole
The 450-square-foot interior is simple and functional, with a modern aesthetic. Expansive glass walls flood the space with natural light. The fir and custom Baltic Birch paneling enhance the exposed steel frame steel-plate floor, and stainless-steel kitchenette. The layout is open, with distinct lounge and kitchen areas, and a Murphy bed and luxury bathroom accommodate overnight guests.
Photograph by Michael Cole
Final Thoughts: Every architect conceives unique build ideas, but not all get the opportunity to bring them to life. E. Cobb Architects Partners’ prefabricated eHAB structure is a vision realized, performing exceptionally well for over a decade due to its durable design and the successful integration of prefabrication and site-built construction. However, don’t let its rugged exterior fool you—the interior offers a warm, refined, and inviting experience every day. cobbarch.com
