Prefabrication experiments - 256 - Operation Breakthrough - 07 - Christian Frey's Universal Building Rib

Architect, inventor and founder of Suspended Structures inc, Christian Frey represents a particular type of industrialist, that from generation to generation sees industrialisation as the way out of lagging productivity issues for construction and for developing affordable housing. Involved in research and in expanding his own visions and building systems, Frey’s most ambitious project is arguably his patent for modular dwellings suspended from a central core. Published in 1967, Frey’s patent, Suspended Module Buildings(US52323465A) proposed a central mast from which cables carried gallow-like cantilevered beams onto which any dwelling unit could be assembled. This class of open systems has been studied and explored in various formats and share the idea of a collective infrastructure with unrestricted floor areas for individualized housing. 

 

For Operation Breakthrough, Frey’s proposal is a toned down version of the patent; what remains is the idea of a sequence of suspended platforms. The rectangular floor surfaces attached to the structural core organize the open framework. Each floor panel structure would be assembled from open web joists to form lightweight slabs cantilevered from and attached to vertical columns. The floor panel loads are carried to transverse rib beams connected to vertical columns. Together, the horizontal frames, rib beams and vertical columns form what the inventor identified as an «URB» Universal Building Rib. The «URB» planning module could be aligned, juxtaposed, stacked to create a spatial variety acquiescing any individualized interior arrangement. 

 

The floor pallets and their open webs and grids connect to vertical ducts for distributing wiring, pipes and ductwork. The unobstructed vertical and horizontal network idealize a dynamic framework expandable in every direction and planned for large scale and small-scale dwelling aggregations. Separating and layering structure and interior organization follows the «open building» tenets. This essence of open systems continues to illustrate the conceptual distance between architectural designed industrialisation and the requirements of manufactured building. This archetype of fixed infrastructure and variable infill does not respond to manufacturing constraints of modular building, it is merely a structural concept. Further it doesn’t address the architectural singularity sought by many architects. Like many of its contemporary open systems, this architect’s dream and obsession gained little traction in industry and in architecture. 

Universal Building Rib and patent section (extreme right)

Prefabrication experiments - 255 - Operation Breakthrough - 06 - Optor Corporation

Organized in the late 1960s, it is unclear how much influence, if any, the building experiments undertaken in the Man and his World (Expo 67, Montreal, Canada in 1967) universal exhibition had on Operation Breakthrough’s proposals and processes. Moshe Safdie and August Komendant, architect and designer of Habitat 67 surely inspired a generation of architects through their vision of housing and construction’s industrialization. Many proposals conceived for Operation Breakthrough argued for similar concepts, pushing the idea of modular boxes, stacked, amassed, clustered or juxtaposed to breed new housing patterns. 

 

Exhibition pavilions have long informed and guided architectural advancements and Expo 67 included many accounts of formidable structural units deployed in multiform varieties. The lineage from exhibit structure to inhabitable space frame was also displayed in metabolism experiments. This theme is also evident in one particular proposal for Operation Breakthrough.  The Optor Corporation project, designed and developed in Montréal, offers a glimpse into potential cross contamination between exhibit structures and housing. The space frame structure of inhabitable tetrahedrons assembled from tubes and hubs defined an open structural concept divided or enclosed by stressed skin panels, service walls or functional units. The support and infill strategy would be easily assembled and as simply disassembled stacked, packed and redeployed for other sites. 

 

The slotted aluminum hub fasteners secured flattened tubular ends slipped into the cylindrical hub’s grooves in a similar fashion to the already well-known Triodetic connector used for many exhibit buildings (see blog post 149). The exact source of Optor Corporation’s design is an architectural mystery. A clue for further investigation may be found in an article that appeared in the ABC journal (Architecture Bâtiment Construction) in may 1968. Author and architect Étienne Dusart described a space frame building system that in all respects seems to be the ideological basis for the Optor system. The author describes the same basic framework and stressed skin fiberglass panels. Sprawling horizontally and vertically the space structure would shape a new type of urban structure that could theoretically grow in every direction as a structured geometric trellis.  Both systems also share the basic triangulated support system and functional units delineating a multiplicity of infilled dwelling patterns. 

Images above : Article from ABC journal ; Image below : Optor proposal

Prefabrication experiments - 254 - Operation Breakthrough - 05 - Commodore Corporation and stacking mobile homes

A mainstream example of the modular, manufactured or mobile home builder’s business model, the Commodore Corporation along with its subsidiaries and partners has been manufacturing affordable housing since the early 1950s. Their segment, the mobile home, although somewhat marginal, represents the successful application of industrialisation to construction. The integrated process harmonizes design, manufacturing and procurement supply chains adjusted to assemble a number of predetermined housing patterns. This combined design and delivery process applied to single-family dwellings relies on a standardized pattern book of models to circumscribe supply chain management, regulatory approvals, quality control, timeline and cost structure while reducing onsite construction risks.

 

This straightforward business model was tweaked in Commodore Corporation’s proposal for Operation Breakthrough. Along with a number of design firms, manufacturers, research and code specialists the company proposed a reinforced concrete megastructure assembled from «precast» or «prestressed» components for high-density frameworks, steel components for medium-density frameworks, and timber for low-density frameworks. These structural skeletons would carry stacked modular volumetric boxes using Commodore’s established process. Idealized as a simple switch from individualized dwellings to collective dwellings the company would mass-produce up to 30 000 units per year. 

 

The superstructure grid, defined by a 14-foot square horizontal module and a 11-foot vertical module, was dimensioned for fitting normalized 12’ wide, 10’ high and from 44’ to 60’ long modular units. The simplicity with which the system was illustrated displays the long-standing disconnect between dwelling manufacturing and collective housing construction. Interfaces between units were simply omitted or neglected. This simple stacking rhetoric avoided the necessary on site joinery and stitching, which must be detailed and optimized with the same quality control rigor associated with the factory to circumvent onsite entanglements. 

 

The Commodore Corporation would oversee marketing, design, procurement, construction management, module delivery and assembly. This comprehensive building model seems ideal. However the necessary parameters and criteria that come along with collective housing, the correct and robust detailing of sound control or fire control, have been replaced by simple stacking. Omitting interfaces and promoting one-dimensional stacking continues to haunt modular construction. Holistic systemic criteria must be included in project design. If not any real advantages of off site construction are quickly lost. 

Proposal rendering - modules inserted into a load-bearing framework

Prefabrication experiments - 253 - Operation Breakthrough - 04 - Spun Plastic Domes

The vast majority of Operation Breakthrough proposals identified some category of modular construction to solve construction’s lagging productivity. Boxes or panels assembled into clusters of medium to high-density housing organizations would offer affordable solutions. The manufactured systems would arrive on site and simply be assembled reforming traditional construction processes. Less prominent, but equally important proposals offered unfamiliar materials, models or strategies detached form conventional prefabrication approaches. One of the more intriguing and eccentric proposals from DOW Corporation, the Spun Plastic Domes, calls to mind the singular dwelling visions associated with Buckminster Fuller’s Wichita house patented some years earlier. 

 

Dow’s polygonal dwelling unit would be assembled from vertical panel service walls that formed a lightweight but deep exterior wall. The wall’s depth included integrated built-in furniture or storage. This useful thickness circumscribed interior space in a served versus service space configuration. The segmented deep structural skin, one to two stories high, supported a half-sphere dome cap. A thin shell cupola rested on panels built from conventional wood stud framing. The dome’s composition was shaped on site. An extruded polystyrene insulating core was sprayed over a metallic framework grid attached to the fiberglass reinforced exterior shell’s intrados. The dome’s interior would then be sprayed with a decorative plastic coating to produce a harmonized interior surface. Each dome covering included a central oculus for lighting and ventilation further rendering its lineage to Fuller’s Dymaxion Unit.

 

Although the dome was the proposal’s flagship element, the envelope service pieces were the innovative idea as they argued for a multi-functional exterior wall. Designed as modular segments, the rounded plan could be individually planned, mixed and matched according to varying uses and compositions. Housing clusters included multiple configurations all articulated to a grid of service distribution points radiating in multiple directions. This service matrix was designed as a field over which the circular dwellings were moored. Anchored by earthwork and foundations to the collective infrastructure and service matrix, the center of each unit was positioned over the service point by a vertical circulation stack that connects lower spaces with upper living spaces. The panel service core would be customized in the factory to include plumbing, electrical systems or any other mechanical device.

Dome dwellings rendering