Prefabrication experiments - 2025-26 - Joyeuses Fêtes | Happy Holidays

 

Prefabrication experiments - 494 - Postwar Prefabs at the Tate (1944)

 

Separated only by a narrow portion of the Atlantic, two allies in the Second World War, France and Great Britain, developed similar government-driven postwar rebuilding programs with a focus on prefabrication. Concrete became the go-to material in France whereas the UK promoted a diversity of systems sometimes referred to as non-traditional construction methods. Even before the war was won, the UK was dealing with a critical housing shortage; efforts were made to support new methods and policies aimed at increasing productivity and encouraging budding industrial models.

 

In 1942, the Burt Committee, part of an Interdepartmental Committee on House Construction, was formed to “consider materials and methods of construction suitable for the building of houses and flats, having regard to efficiency, economy and speed of erection”. Sustained by these attempts regarding prefabrication, Winston Churchill promised 500 000 new homes beginning in 1944 to absorb shortages and provide affordable options for young servicemen returning from the front lines once the war was over. The Tate Gallery held an exhibition of prototypes in the same year - the Exhibition of Prefabricated Houses - to increase knowledge about the potentials of these new building methods.

 

Along with some international examples, UK's industry presented the Portal's Palace, the Arcon, Uni-seco,  and Tarran bungalows as non-conventional or non-standard systems. Traditional construction methods for housing in England relied on brick and mortar, stone load-bearing walls and tile roofs. The new building methods employed steel or aluminium, and new materials like asbestos, which were largely foreign to vernacular approaches. The Pheonix is a notable example of light steel components being used to quickly assemble a house that was meant to last 10 to 15 years. Most of these systems were intended as basic emergency dwellings and earned a bad reputation as they were evaluated by standards and criteria different from those for which they were designed. The exhibit also showcased the AIROH houses, also known as the Aluminium Bungalow, proposed by Aircraft Industries Research Organisation for Housing which was to redirect aeronautic infrastructure and production capacity used in the war effort toward home building. 

Top left: Tarran Bungalow structure; Top right: Tarran Bungalow; Bottom left: Exhibition at the Tate; Bottom right: AIROH house section

Prefabrication experiments - 493 - Exhibiting Prefab Potentials

 

Architectural pedagogy established during the late nineteenth and early twentieth centuries led to a new type of specialized architectural practice influenced by production methods and material innovation. Within this context, production and industrialized construction were considered as either the enemy of the traditional artisan or the future of more efficient architectural processes promoting rational planning. As industrialization evolved and was envisioned for building, architect-driven prefab narratives defined some iconic prefab experiments. Modern architects inspired by these inventions supported the collective mediatic dissemination of prefab systems toward innovative affordable housing.

 

Architectural prefab exhibits presented projects and prototypes communicating how these new processes were becoming mainstream and rerouting production from on-site to off-site. Precedents range from marginal organizations to large-scale artistic interpretations. Progress of Prefabrication (March 9-28, 1944) was staged by the Architectural League of New York. Founded in the 1880s the League was a focal point for progressive architects initiating debates and discussions around the evolution of their contemporary architecture’s tools and methodologies. The exhibit showcased models, drawings, and company catalogs to portray what was to become the future of design for fabrication and simple site assembly. 

 

The Built in the USA (1932-1944) series presented at the MoMA (Museum of Modern Art) also provided an optimistic vision of prefabrication's potential and its contribution to an American modernism. This tradition of promoting USA's role in advancing prefab ideals in architecture through rich exhibits and accompanying literature was reaffirmed at the MoMA from July to October 2008. Home Delivery, Fabricating the Modern Dwelling curated by Barry Bergdoll and Peter Christensen combined a rich historical narrative with a series of prototypes to illustrate a renaissance of prefab theory linked to advances in manufacturing. These are only three examples of a long and rich history of using exhibits to increase uptake in prefab interest and improve its credibility to inform efficient practice. The Progress of Prefabrication put on nearly 80 years before Home Delivery, addressed some of the same challenges of bringing architectural prefabrication to market as its conceptual foundations are sometimes more representational than practical.

An excerpt from Built in the USA (1932-1944)

  

Prefabrication experiments - 492 - The Turning Point of Building

If precast reinforced concrete panels epitomized prefab production in the 20th century, flexibility and adaptability emerged as two symbolic theories developed by architectural pedagogy as a way forward for linking mass production’s required repetition with architecture’s ingrained culture of bespoke designs. Iconic explored this tension through the systemic potential for industrialized elements to accommodate various functions and organizations based on a set number of configurations and parts. 

 

Literature on this type of modularity is broad with flagship architects like Konrad Wachsmann arguing for a radical change in building construction.  From airplane hangars to universal spaces and connectors for houses, his book published by Reinhold in 1961, The Turning Point of Building outlined a variety of strategies for modernizing structures and design. Predominantly articulated to rigorous grids with replicating joinery at each intersection to deploy thick surfaces in every scope and scale, Wachsmann's explorations were inspired by furniture making, Mero connectors and by Buckminster Fuller's octet trusses for packing and spanning spaces. The publication establishes the space frame as an efficient strategy for a myriad of arrangements and large open spans. The open-plan concept, above all others relates modern architects' view of innovation in architecture to skeletal building systems. Using the universality of grids and their joints, Wachsmann argued for simple connections toward an infinite number of aggregating and tectonic affirmations.

 

The elimination of bearing walls and the reduction of weight to the bare minimum required for structural performance would optimize both adaptability and rationalize costs. Today, these principles first explored in the late 19th and early 20th centuries are providing a renewed framework for industrialized building systems. The exploration of grids and modularity still represents a large portion of architectural theory as well as practice and pedagogy, aiming to bridge the gap between mass-produced components and customizable arrangements. Identified as platform theory applied to architecture, the ideas expressed by Wachsmann as a turning point are again being highlighted as ways to increase prefab's social acceptability by reinforcing systemic production without the echoing connotations of subpar designs. 

Excerpt from The Turning Point of Building

Prefabrication experiments - 491 - From precast concrete plates to « Flying Panels »

 

Above all other systems, one embodies industrialized construction’s input on mass produced serial architecture. From the mid 1940s and throughout the decades following the second World War, the precast concrete panel manufactured to shape hives of dwellings from similar slabs and walls was deployed in Europe and in the Americas as a symbol of construction reform as well as innovation. 

 

Its plainness is at the root of its prolific and large-scale application; sheets of concrete cast in standardized thicknesses, with window openings and facing materials were produced in factories to be delivered and stacked in repetitive organisations. Either dry assembled or bonded with mortar over continuous and extending steel reinforcements knotted in a monolithic framework, the «Panelki» panel building asserted the application of centralized policy frameworks to architecture. 

 

Flying Panels, a recent exhibit, showcased the concept of this building system, lifted buoyantly into place, increasing output on a war-ravaged continent becoming synonymous with post-war prefab. Opened in 2019 at ArkDes, Sweden’s National Centre for Architecture and Design, the exhibit was accompanied by a catalogue including a variety of texts reinforcing the sheer scale achieved by concrete panels. Researched and curated by Pedro Ignacio Alonso and Hugo Palmarola, the project elegantly portrayed the globalized use of these artificial stone plates inspiring offshoots in diverse countries that faced similar challenges in the supply of affordable dwellings. Models, publications, and posters, all relate the attraction and dissemination of a controlled procedure for producing communities. The almost choreographed movement of cranes raising and setting panels horizontally and vertically multiplied identical arrangements, adapted to their contexts through a varied patchwork of facing materials or panel geometries. 

 

While reinforced concrete, in today's carbon conscious construction environment has designers searching for alternatives, the Panel Block’s role in modernity is undeniable as is its contribution to developing our current base of industrialization strategies in other materials. The case in point is mass timber (cross-laminated timber) which is being proposed in an analogous type of sheet and surface-based strategy toward affordable housing. 

An image from the exhibit

Prefabrication experiments - 490 - Looking Forward to 500

 

The first 10 blog posts (January – April, 2014) acknowledged both iconic and lesser-known prefab experiments, some productive and many flops, with the intention of elucidating promises and challenges related to offsite construction. Twelve years later, the blog will reach a milestone that seemed at the time, highly improbable: 500 posts.  Conferences, articles, publications, research endeavours, study days, and three exhibits have grown out of this ongoing exercise.

 

Looking back at 489 posts retracing the history as well as current experimentation, the challenges to industrialized construction are unchanged. The increased use of manufacturing methodologies in construction again appears inevitable considering lagging productivity, onsite wastefulness, and reduced affordability, however these methods remain marginally applied relegated to certain types of projects, as architectural singularity, outdated perceptions along with outmoded building processes remain the crux of the problem. Research - historical, creative and codeveloped - particularly within the AEC disciplines remains robust and a celebration of this fertile field of exploration will be the subject of the next 10 blog posts. 

 

Exhibits, literature, and prototypes have all been delivered to highlight how prefab would radically modify construction culture. The Dream of the Factory-Made House (Herbert, 1984), Kelly's The Prefabrication of Houses (1951), Wachsmann’s The Turning Point of Building (1961), The House as a Product (Vogler, 2016) and Refabricating Architecture (Kieran and Timberlake, 2003) all manifested and conveyed the prefab promises of their era. Curating prefab played a similar role. Architecture et industrie (Centre Pompidou, 1983)  Home Delivery (Moma, 2008), and Flying Panels (ArkDes, 2019), celebrated the diversity and influence on architectural praxis and education. 

 

Along with curating and publishing, government-endorsed exercises have disseminated knowledge aimed at enabling prefab to successfully infiltrate the market; Operation Breakthrough from the late 1960s remains the most famous. The experiments published on this blog incorporate this rich and diverse history of prefab construction specifically in their effort to reunite two fields represented by conflicting values; architectural values of singularity and the extreme production efficiency values which regard architecture's take as frivolous. These divergent views still embody the inherent complexity associated with construction’s industrialization. 

An excerpt of experiments from 1-489

Prefabrication experiments - 489 - 3D Printing - An Onsite Assembly Line

 

Considered for the designed-to-order fabrication of small complex objects in the recent history of additive manufacturing, the technology's translation to building has spawned a large amount of analogous exploration, though mostly linked to marginal prototypes. Precisely depositing a fluid concrete or clay composite layer-over-layer numerically controlled to produce an extruded form is the basic idea of these horizontally textured vertical bearing walls. 

 

Timber beams, steel purlins, or any other type of spanning element can be attached to the walls to cover interior space. Vaulting layers has also been explored and experimented with to produce compressive monomaterial structures. In all cases either a robotic arm, or a gantry type crane carrying a nozzle deposits material according to instructions contained in a 3D model, plotting in x-y directions with the z axis being developed at a relatively slow pace, which allows the material’s adequate consistency to settle and support the next layer. From bus stops to micro dwellings, and even two to three-story collective housing, 3D printing is being promoted as a low-cost alternative to conventional site cast concrete. 

 

The mass-construction archetypes are produced on regular, printed foundations or over a slab on grade. Using these techniques to produce housing implies delivering material and machines on a just-in-time basis using only what is needed, reducing costly and wasteful formwork associated with reinforced concrete construction. 

 

3D printing tehniques and methods are progressing rapidly. Demonstrated for continuous printing of linear objects over a conveyor, the Blackbelt 3d printer is showing what can become an alternative to bearing structures, where beams and other types of dimensional components could be made onsite and then simply bolted together or assembled with mortar in a 3d printed kit-of-parts. Producing complex components can further optimize the technology's use by providing any shape needed to adjust to site conditions. Bringing the required digitally controlled tooling to site points to new potentials in terms of size, scope, and shape as the normal transport criteria that limits sizes and capacities need not apply.

Blackbelt 3D, printing linear objects over a conveyor

Prefabrication experiments - 488 - Modern Dry Masonry for Cleaner Sites

 

Masonry construction is commonly known as a wet construction method. The site-intensive process of laying masonry uses binders, with hydraulic lime being the most common, in which water activates a chemical reaction to harden and bond unit elements (modular or irregular) in an infinite variety of stacking arrangements. Historically, Roman opuses or opera symbolize masonry construction's durability -  some of their compressive shapes still stand thousands of years after they were built. Masonry owes its strength to both the permanent binding and the geometric stacking of elements with width and shape as indicators of performance. Bricks, blocks, and stones, are piled following modular dimensions or distributed informally to fill out walls, and more spectacularly arches, domes or vaults using temporary supports as elements are allowed to bind and cure. 

 

Masonry is associated with on-site messiness as liquid binders are mixed and troweled onsite. Dry masonry, common in contexts lacking resources and knowledge to mix robust binders, was developed as a structural alternative based not on the adhesion between units and mortar, but on how elements are fitted together, intertwined in structural resistant geometries with no binding agents except the units' form and weight. This type of clean/dry masonry construction inspires modern alternatives that relieve intensive site conditions requiring no specialized labour.

 

Three startups, Plaex™, Systeme3™ and Legioblocks^™ all share a renewed interest in simplifying masonry construction by either minimizing or even eliminating messy binders. Each system is manufactured with shapes or profiles designed to stack, interlock and snap together like toy Lego™ bricks. All three systems propose load-bearing walls that support other building elements to span horizontal spans. Systeme3™ for example showcases the use of hollow core slabs supported by precast concrete beams and posts to form an industrialized building system. The skeletal structure is infilled with the interlocking blocks which are then layered or insulated to form single- or multi-layered wall systems. Promoted on their ease of assembly, the three systems also promote new materials that include recycled content. Dry Interlocking also introduces potential disassembly and circularity to contemporary masonry construction. 

left: Plaex™, center: Systeme3™ and right: Legioblocks^™

Prefabrication experiments - 487 - The Architecture of Standardization

Since modernism pioneered new architectural possibilities based on industrial techniques and materials, architects have developed an enigmatic love-hate relationship with industrialized construction. In best cases, they have proposed prototypes ingrained with a capacity for mass production, fashioned from off-the-shelf details in the name of standardization; Iconic, well-known architects presented prefabrication as a model for mass housing. Others have been highly critical and probably one of the reasons prefab has fallen short of attaining the same large-scale successes of manufacturing in other sectors. Reaping prefab's advantages requires deep normalization. As presented in mobile home manufacturing in the United States, or in panelized precast concrete systems of the  Soviet era Gosstroys, production was tuned to economic objectives. This type of mass-produced housing was highly criticized by architects for its reduced design value.

 

Architects have espoused the narrative of standardization without the commitment to standardized design. Repeating a singular extruded curtain wall profile in a building is the type of detailing architects have come to propose as their understanding of standardization. Widespread standardization has been achieved in the building industry demonstrated by every part and piece of a building being catalogued, specified, purchased and delivered with respectable lead times; any big-box hardware retailer depicts this comprehensive normalization.

 

Using made-to-stock ready-to-use components to build a house or building is one of the reasons the fragmented building culture remains a successful albeit inefficient model of production. Contractors buy and deploy these elements without scrutinizing low-design value whereas architects will try to redefine elements arguing for the added value of singular design. This singularity associated with architecture is a complete non-standard approach leading to higher costs and increased production waste. The added value of the architectural design process is vital but must be harmonized and weighed against the required changes in production values and methods to achieve atypical designs. Standardization along with designed for manufacturing efficiencies require a grasp of production to attain scaled replicability and represents the only positive way forward for a stagnating industry. 

Walter Gropius and Konrad Wachsmann's Packaged House

Prefabrication experiments - 486 - The Patterns of Timber Framing for Teaching Robots

 

Envisioning the streamlined fabrication of customized pieces, panels, or chunks delivered just-in-time, for the quick, and easy assembly of a house or building has been the ambitious value proposition of many industrial protagonists. Some have succeeded in harmonizing their business model with a localized specific demand; however, the more generalized industrialization of construction required to increase productivity and respond to the growing challenges of onsite construction is still elusive. The required reform toward production in construction, is all-encompassing from the small onsite contractor to the large developer. The industry is too bogged down by old habits; manufacturing requires upfront investments that make it difficult to compete in terms of costs and agility with conventional builders. 

 

A startup based in Alberta, Canada, is striving to reform the prefab producer’s business model based on a completely integrated Factory Operating System that deploys lean robotic production to streamline the framing of house panels for floors and roofs. Promise Robotics is looking at prefab in a new way by understanding how robots can be taught to assemble project specific and industry standardized framing patterns, in a just-in-time factory-to-site delivery process. A relatively small production bay is controlled by the file-to-machine data-driven process. The robotic arms can switch from lifting, cutting, placing, aligning, nailing, seamlessly executing machine learned patterns orchestrated to produce a 40-foot wall framed panel in 8 minutes. 

 

Two robotic arms working in conjunction, borrowed from the automotive industry, were set up to learn from a local manufacturer's production process and endeavor to reproduce timber framing in idealized AI-driven conditions. From this research and development, the company is proposing to market agile «flying factories» all over the country to help increase supply and encourage the adoption of new prefab ideas. Recognizing that housing construction is not only a production problem but includes material management, supply chain harmonization, and factory to site logistics, their value proposition includes an operating system that outlines and manages every part of the process, including the choreographed robotic assembly of wall components. 

See article in  https://www.canadianmanufacturing.com/manufacturing/promise-robotics-opens-new-homebuilding-facility-in-alta-312995/