Prefabrication experiments - 13 - Tournalayer for home construction - a machine for casting houses - US patent 2593465A

Concrete is a magical material that has fascinated architects throughout history. Vitruvius in his ten books on architecture (De Architettura) referred to the cindering of limestone as producing a magical powder that when mixed with water hardened to a stone like substance. Liquid stone, the monolithic material composed of water, sand, Portland cement, and gravel poured over and around a grid of steel is one of industrialisation’s great building materials. The experimentation with reinforced concrete contributed to modernism as it lent itself to the idea of frame structures or slab structures freeing the exterior and interior walls from their historic structural roles.

Within modernism’s love affair with concrete, many shared the dream of the mass-produced concrete house or housing system. Prototypes ranged from on-site produced to the off-site pre-cast. The difference between the two methods was the amount of work done in the factory. The two extremes of on-site or off-site also induced a potential hybrid of maximizing reinforced concrete’s potential with the flexibility of on-site construction. Thomas Edison’s process for pouring buildings, in a single pour, was one of these proposed hybrids. Edison’s patented system of pouring houses developed in 1917 looked to optimize on-site construction by industrializing the formwork and the pouring process into one synthetic strategy.

Having limited success Edison’s system conceivably foreshadowed one of history’s most daring proposals. Having experience in the invention of ground moving machines Robert G. Letourneau of Letourneau incorporated set out to invent a machine that could transport concrete moulds and forms on-site, set them in place, and then lift the forms to be transported elsewhere once the pour was complete. The enormous machine was the basis of the Tournalayer Home construction process.  

The Tournalayer’s capacity to carry the factory to the site was based on a double skin mould. The mould in which the concrete was poured was set on-site and lifted when the concrete was set. Analogous to a double sandcastle mould into which one could pour concrete, set the mould onto the ground, tap and then lift, leaving a surface skin or a monolithic concrete shell. The formwork included windows, doors and various technical openings. The houses were simple in design but could be varied into a number of models within the Tournalayer’s basic modular dimension. Built in different countries from the United States to a few prototypes worldwide, the notable success of the concept was the ability to use, set, lift and transport the formwork bringing industrialisation of building the building site.

The Tournalayer at work - photo link  

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Prefabrication experiments - 12 - Green's ready-built solar house by George Fred Keck

Industrialisation developed prefabrication for the generic production of housing. The mass production strategies needed to successfully generate, produce and deliver the factory made house required the least amount of product differentiation. Architecture, framed in its much larger perspective including prefabrication, has a more site-specific objective.  The long lasting contradiction between prefabricated architecture and its difficulty in addressing context has always been a challenge for prefab and a driving force for the flexibility of on-site building.

Prefabricators seldom explored universal mass housing strategies that address different contexts as this contradicts productivity of scale. One of the marginal exceptions to this general rule was the Solar house designed by George Fred Keck for The Green Ready-Built House Company. George Fred Keck, was an American architect known for his work on exhibition houses; "the house of tomorrow" and «Chrystal glass house» both prototypes that were built in Chicago in the 1930’s to display new building methods and design strategies.

Both houses, although differing in plan, demonstrated Keck’s willingness to optimize the use of solar energy. Predating solar passive housing strategies by decades, Keck proposals made use of large glazed walls using double-glazed insulated glass and an intelligent composition of rooms relating to the sun’s path. The circular, decagon, plan of the «House of tomorrow» built in 1933 used large insulating glass panels as a skin to a standardised modular steel skeleton in composing what is referred to as America’s first glass house.

While the Green's ready-built solar house did not use Keck’s the circular plan or the completely standardized glass and steel components, the small prefab house was designed for an optimal south facing lot with rooms on the glazed side. The south-facing wall was composed of large windows, louvers and a large horizontal sunshade optimizing heat gain in winter and shading in summer.

The «solar» house was a simple rectangular plan using stressed skin panel construction. Keck also designed variants of the plan for four different site configurations understanding that the south facing lot strategy limited the proposal’s capacity to be adapted to a greater number of sites reducing its scalability. The variability Keck proposed tried to bridge the gap between industrialisation's need for the generic and the architect's responsibility to understand context. This effort to create a site-specific prefab had limited success and still remains a challenge of the industrialisation of building systems.

Add from Popular Science August 1946

Prefabrication experiments - 11 - The Mobile Housing Unit - US patent 2499498 A

The diversity of building construction solutions proposed at the beginning of the 20^th century displays that era’s preoccupation with housing. Prefabrication of building components and assemblies as outlets for industrialisation contributed to the invention of novel architectural systems. Along with the new machines, Industrialisation’s division of labour and hierarchal systematic production methods influenced the evolution of architecture from a site-anchored artefact to a factory-produced item. 

The commodification of architecture determined ideals of integration, standardization, and modular coordination as strategies for cost reduction, mass production and the long-term suppleness of systems architecture.

Monolithic units or boxes (see Industrialized building systems for housing, MIT press, 1967), often referred to as modules, are preassembled volumes completed to various degrees in factories. The modules can be used as an autonomous housing system or assembled, stacked, and integrated to form multi-unit buildings.

The «Mobile housing unit» patented by John Hays Hammond Jr in 1947 explored the monolithic unit or module both as a housing unit and as a condition for the adaptability of housing over time. The proposal included a support structure that served as a crane during construction and also served to receive and join each unit in the whole building system. The support structure as the essential component of the building erection allowed each unit to be stacked and disassembled in reaction to the varying and evolving needs of the occupants.

The building as a support structure and crane essential in the building’s erection is perhaps one of the most experimental visions of building to come out of the machine age, even though machines for building have been an integral part of architecture and its literature throughout history.

The scheme’s objective was mobility. Housing was not viewed as a static building form but a moveable and adaptable commodity reacting to lifestyle changes or the diversity of user demands. The industrial and architectural ideal of building with modules took many forms through the 20^th century: Kisho Kurokawa’s capsule tower, Moshe Safdie’s habitat 67, or the Zachry System of modules being the flagships of modularity.

Mobile Housing Unit : Patent drawing

Prefabrication experiments - 10 - Aircraft Industries Research Organisation for Housing – the A.I.R.O.H. house

Prefabrication, «the oldest new idea» in architecture is often related to the ideal of affordable mass-produced housing. Many experiments, however, when studied within their social and political contexts convey less progressive values relating more to the economics of industry and less with the noble value of quality housing. Well known experiments such as the Lustron house or even Buckminster Fuller’s Dymaxion house arose from the government’s efforts to reactivate and recycle «wartime» industries in the wake of their declining production toward the housing industry. Factories, workers and material use were imperatives to the sustainability of the war effort and instrumental components of the post-war prefabricated house.

This symbiotic association between state and industry, in Great Britain, was the basis for one of the major experiments in prefabrication by an industry not concerned with housing. The Ministry of Aircraft Production (MAP) established, A.I.R.O.H, to sustain production capabilities of the aircraft industry through the post-war economic downturn threatening both the aluminium and the aircraft industries.

The AIROH house is not really an architectural experiment as its logic stems solely from an industrial perspective supported by the MAP. It is however an interesting experiment in prefabrication in as mush as the house was completely factory produced in a manner analogous to aircraft production. The simple bungalow volume was divided into 4 sections or modules completed in the factory and delivered on site. Sitework was minimal and limited to foundations and infrastructure connections. The aluminium frame was somewhat of a panelized system similar to early stressed skin aircraft construction (walls, floors, roof acting together to minimize module deflection). The semi-monocoque shell envelope was filled with a mortar-based insulation. The plan was a simple straightforward bungalow that offered little in terms of spatial innovation and little in terms of aesthetic research.

When it finally reached production, the AIROH design, was 50% more costly than what the housing authority accepted at the time. The MAP was a powerful lobby and the Termporary Accomodations Act of 1944 accepted the AIROH house as one of their potential products and ordered over 50 000 houses. The system was however, a costly alternative to what the competition was offering and lacked the added value of architectural design or the ordering flexibility of on-site building. The AIROH house was more of an industry-feeding political strategy than a housing solution.

On-site assembly of the AIROH house modules