Prefabrication experiments - 180 - Exhibition houses - 01 - Roger Lee's tract house

Throughout architectural history, exhibit houses have showcased and shaped new visions, optimistically making them accessible to everyone. Modernism, inspired by industrial development, united corporations, architects and entrepreneurs seeking a new domestic architecture, its production and its distribution. After the great wars, new materials, construction methods and products flooded the market offering innovative conveniences and an architecture based not on local vernacular but on what had become architects’ global pursuit, in the west, an international style based on modernist dogma. 

Prefabrication while remaining marginally applied became a tool for representing this new post-war domesticity in the USA coalescing European modernism with North American values promoting the single family dwelling as a tool for personal freedom and emancipation. A tract house developed by architect Roger Lee, well-known for his application of modern principles, for the East Bay Homebuilders Association’s entry at the 1952 California International Home Show displayed this conceptual union through its modern tenants: the modular grid, horizontal continuity between indoor and infinite outdoor space. A trade association, an architect and a builder assembled to form a formidable team to put forward an essay on housing. 

The tract house was a modest timber structure based on a 4-foot grid widely regarded, at the time, as a way of attaining efficient modular coordination based on material and product manufacturing dimensions. The plan was divided clearly into served and service spaces, another link to modernism, and the prototype included a fully equipped kitchen and bathroom with all modern conveniences. Brick walls and concrete floors anchored the house to its generic site while horizontal brickwork composed the fireplace wall as the focal point of a completely open relationship between kitchen and living area. A covered courtyard adjacent to the kitchen delineated by deep roof overhangs protected a children’s play area. 

The house offered a glimpse into what the modern house could look like including its simple straightforward lines, new building materials and technological components. The house would become a streamlined production from design to assembly; a commodity that would benefit from industrialization as other products had. Time has shown us that although popular with a progressives the modern house seemed strangely unfamiliar and marginalized by a relatively conservative marketplace. 

plan and photograph from House and Home - may 1952

Prefabrication experiments - 179 - Geometries - 10 - Pier Luigi Nervi and elucidating structures

Geometry underlies any architectural composition. Since antiquity the compass, straight edges and strings were used to set out building foundations relying on the rigorous organization of lines and curves. Shaping architectural form, proportioning construction elements, and regulating architectural space can all be related to arithmetical constructions. Modernity not only continued using geometry as a designing device but celebrated geometry as a way of reforming architectural language from classic geometries to industrial production based geometries. Modules and standardized spans replaced golden sections or daisy wheel compositions. Geometry became the basis of celebrating structural form for architects and engineers. Pier Luigi Nervi’s designs reveal a fascination for showcasing structural behaviour through geometric shapes. His Palazzo Del Lavoro designed in collaboration with Italian architect Gio Ponti inaugurated in 1961 for the Turin Worker exhibit celebrated 100 years of Italian unity. The flagship building exposed Italian industry and would later be converted into a technical school.  

Spectacularly modular, its 16 square topped mushroom columns are juxtaposed to produce a great exhibition space. Each 25 m tall monumental and tapered reinforced concrete columns are fluted to showcase load transfer from top to bottom. The cruciform columns have a 6 m x 1m wide base section. Each column supports a 40 m square plane head composed of steel radiating beams also tapered from their center to their edges to explain the increasing stresses toward the center mast.  Each element was prefabricated and the structure was completed in just 18 months. The square mushroom columns are juxtaposed to construct a 160 m square canopy. Each mushroom head is separated from its adjacent slab by a 2m skylight reinforcing both the modular geometry and the sensation of being underneath a colossal covering. Mezzanine galleries lace the interior space and reveal geometric ceilings using the same type of isostatic rib slab employed by Nervi at the Gatti wool factory which employed geometric patterns as ribs to minimize bending moments in a two-way slab system. The building’s all glass envelope frames the basic overhead plane supported by equally spaced columns each celebrating the basic geometry of a square layered with radial sectors pointing to the central column. 

Column Elevation

Prefabrication experiments - 178 - Geometries - 09 - Fritz Haller's mini, midi, maxi

The systems approach to building, creating a whole from the rigorous organisation and coordination of disparate components is one of the enduring principles of architectural modernity applied to building construction. To this day buildings are organised and assembled through systemic and dimensional coordination. The four-inch-cube building module proposed by Bemis in the early twentieth century illustrated how this basic geometric unit could establish a geometric harmony throughout a building’s organization and its parts. The unit to whole relationship based on the smallest dimensions regulating the largest components’ dimensions inspired architects to define coordinated languages or syntaxes based on multiples. 

One of the most convincing attempts at defining agile building systems through modularity was proposed by Swiss architect Fritz Haller. Well known for his association with manufacturer USM for a line of modular furniture, Haller applied his modernist education to develop a scalable construction system applicable to three building types in the early 1960s and 1970s. The mini for houses and residential lightweight construction, the midi for intermediate commercial grade construction and a long spanning MAXI version of the component based system for large structures. The three skeletal steel systems employed a similar approach. Prefabricated elements for columns, girders, main beams and panels based on a modular 60cm / 120 cm grid normalized construction details and simplified coordination while permitting multiple and adaptable functional and spatial patterns. Haller also applied this integrated vision to city structures idealizing as Konrad Wachsmann did in the USA a type of lightweight structuralism adapted to any use. 

The mini, midi and maxi systems were based on a similar square grid. Only the systems’ components were scaled in relation to increasing spans. The efficient two-way space frames, constructed from folded plate sections made use of optimal structural sections to create lightweight trusses with open webs. The unrestricted floor plates simplified systemic coordination though the structural members’ open webs. Passing wires, ducts or conduits was as adaptable as the systems planning; Each system could be changed throughout the building’s life-cycle. An example of open planning applied to buildings Haller developed theses scalable systems to address a need for systemic adaptability to give buildings the capacity to evolve.

Fritz Haller from furniture to cities