Prefabrication experiments - 72 - Procédé Fillod metallic buildings

Pre-industrialised building culture assimilated processes, techniques and particular building characteristics from the exchange of knowledge between specialized guilds. The craftsman was the focal point of building production. In a wide-ranging shift, industrialised building culture placed the manufactured component and its fetish materials: plastic, concrete, steel and glass at the heart of new building praxes. Within this modernization and its material pallet, steel and its production became emblematic of a revolution in building.  Recognized for its versatility, precision and meticulous manufacturing, steel’s progress generated smaller astute profiles, stronger alloys, thinner laminates and exact engineering. From early cast iron houses to Barton Myers collaboration with Stelco, a plethora of kit-of-parts systems embodied the correlation between steel and the pursuit of an industrialized architecture: continuous production toward economic benefit.

Steel and its use in construction was endorsed in most industrialized countries.  In France, the GEAI (Groupement pour l'Etude d'une Architecture Industrialisée) loosely translated as the Industrialised Architecture Research Group, established in 1962, explored and examined building experiments in various materials and methods. Specifically in regards to their simple constituents, their agility and their dry construction methods, steel frame and component systems expressed a «mass-customizable» strategy for building encouraged by the GEAI. Frame (post and beam) systems supported countless grid patterns, arrangements and functions. The quickly erected steel skeleton was a framework for variable but coordinated envelopes. The skeletal components were profiled, cut and bored in the factory enabling an orderly and methodical type of «Meccano» construction.

The «Procédé Fillod» developed by Constructions Métalliques Fillod was typical of steel’s potential and development leveraged toward building construction. Furthermore the Fillod systems illustrate a conceptual model still in use today. The Fillod processes included both folded sheet material and laminated post and beam elements. The folded plate material was used for wall panels and notably as permanent concrete slab formwork for floors, foreshadowing present day steel floor construction.  Fillod metallic buildings evolved from early 1930’s patents to school building systems in the late 1960’s. Analogous to Lustron in the US and Dorlonco in Great Britain, the skeleton and skin approach to industrialized building systems proposed a flexible and adaptable language of coordinated parts.  Fillod’s simple steel framework was articulated to a predefined factory-optimized dimensional modularity.

Procédé Fillod - open steel framework

Prefabrication experiments - 71 - The FHA small house planning guidelines

The federal housing administration (FHA) was established in 1934 as part of the post-depression Housing Act during Franklin D. Roosevelt’s administration as part of his New Deal for the United States. The FHA aspired to expand accessibility and to renew deteriorating housing stock. The depression had severely crippled America's housing economy leaving many ill housed or unable to respect mortgage engagements. The FHA guaranteed existing mortgages and underwrote vast housing projects propelling the American economy and the consumer toward new standards for housing. As part of its mandate the FHA attempted to regulate both supply and demand for an acceptable dwelling type. The small house planning guidelines published by the FHA were a major part of its symbiotic strategy that promoted an economic model, a lifestyle, a house type and a construction method (the basic wood balloon frame) in favour of homogeneous territorial development.

The small house guidelines presented a variety of strategies built around simple square plans, traditional pitched roofs and straightforward spatial options. The basic house consisted of a one-floor living space with no basement and no attic.  The small house prototypes shared a square plan, 2 bedrooms, closed kitchen and bath and an open relationship between the entry and the living area. The house’s wood frame stood on a concrete slab while the roof was built up from standard wood rafters or king post type triangular truss construction. The small living area's horizontal and vertical spans reduced costs and simplified construction. This standardization was in line with American building culture. The balloon frame and vertical two by four stud construction was an ideal system for these small houses as the components were continuously produced and already a major constituent of the American building industry. 

The wood framed buildings employed standard sizes, spans, arrangements and components, which simplified construction and material procurement. Assembly lines were set up directly on tract housing development sites. Process staging and modular standards for foundations, framing, services and finishes contributed to a veritable theatre of construction management both in terms of industrialization and prefabrication of certain sub-assemblies (kitchens, baths). Systems were simple and customization minimal. The FHA guidelines were a major ingredient of America’s post-war territorial development.

Excerpts from the FHA «Principles of Planning Small Houses»

Prefabrication experiments - 70 - S.I.R.H. Modular housing system by Jean and Claude Prouvé

The twentieth century introduced a plethora of new services to buildings in order to enhance comfort. From electrical services to plumbing and air conditioning, simple pre-industrial building culture evolved into a complex entanglement of systems and services. Management of this entanglement became a dominant theme of building technology. Modern methods of construction are for the most part concerned with setting clear, synthetic, efficient and interchangeable paths for each building system. Evolving from an elucidation of systems, «open building» theory was articulated to the sorting out of building systems and facilitating their flexibility over time.

This type of «open» and «evolving» approach to building was characteristic of prefabrication strategies during the latter decades of the twentieth century. The avant-garde experiments of the early twentieth century and the early failures of the factory mass-produced dwelling gave way to a new generation of architects arguing for mass produced flexible and adaptable component systems that would respond to the variable needs of the modern dweller.

The well-known French designer and architect Jean Prouvé was recognized for his research into industrial processes and notably for his exploration of the curtain wall. His legacy is well documented in architectural history. His dream of an industrialized architecture was also carried by his son Claude Prouvé and was expanded through the invention in 1973 of a modular monocoque component system. The father and son collaboration on the  «Société industrielle de recherche et de réalisation de l’habitat» industrial research for housing project was based on the clustering of geometrically compatible structural foam injected shells for floors, walls and columns.

The post and panel component system could evolve over time, be repurposed, replaced and even disassembled once no longer needed. The main differentiating point between this open system and the plethora of component systems designed during this period was its vertical mechanical shaft used to distribute mechanical and electrical services. The shaft was used as a core element around which the dwelling’s services, bath and kitchen, were articulated leaving the remainder of the composition open to a modular assembly of 3.8, 5.3, 7.6m sided volumes with a height of 2.5m. Only one of these prototypes was completed.  These meta-industrialized systems failed to take root, as housing, collective and single dwellings, continued to be produced independently.

Axonometric drawing - system components

Prefabrication experiments - 69 - Hope's Windogrid

The curtain wall is conceivably the most important revolution in modern building culture. Originating in the nineteenth century and honed throughout the twentieth century, this revolution introduced the glass building but more importantly supported the disconnection of the building’s envelope from the building’s structural system. The traditional envelope composed of a massive enclosure supported by each floor was substituted by vertical and horizontal lightweight structural profiles hung from the building’s edge. This grid of structural members could be fixed intermittently to a building’s floor edges and sealed with glazed, insulated or decorative panels. This separation of structure and skin released the façade from classic structural rhythms.

Lightweight materials transformed building in Europe and in North America and were consistent with new production capabilities and contributed to improving multilevel buildings, which commanded lighter materials in order to achieve greater vertical spans. Robert Davidson discussed the curtain wall and the separation of structure and skin in a May 1947 article from "architectural Forum". Davidson illustrated the flexible assembly of vertical supports on the edge of slabs as the main constituent of this nimble building strategy. The flexibility allowed for the building’s «structure and skin» to obey different orders. The light glazed walls also decreased traditional massive wall loads. Many different companies developed curtain walls in steel and in wood but most used aluminum sections converging the material’s lightness, its precise production potential and postwar economic downturn for the aluminum industry.

Post-war school building systems were especially conducive for curtain walls as new pedagogy demanded diversity in planning and adaptability while governments demanded systems that optimized prefabrication, industrialisation and transfer of military technologies to civilian use. Although it is impossible to choose one curtain wall system to portray an industry with many variants, Hope's Windogrid did combine the three main constituents that characterise both the forbearers of the modern curtain wall and present day technology: floor edge anchors, vertical and horizontal mullions, and separate pressure caps. Henry Hope and Sons ltd proposed a system for continuous fenestration, which separated steel mullion bars from an extruded aluminum cap section, which held glazed panels in place. The steel bars were fixed to the edge of slab condition while the aluminum grid was set apart from the structure, creating a continuous glazed enclosure.

Windogrid Detail