The DFAB House: Digitizing Construction

Swiss Plateau region, Dübendorf, Switzerland

“researchers from eight ETH Zurich professorships have come together with industry experts and planning professionals in a unique way to explore and test how digital fabrication can change the way we design and build.” 

– DFAB House

Exterior & Interior views of the DFAB house

The construction industry ranks among the least digitized sectors globally. In the United States, construction is second to last on the MGI’s digitization index, while in Europe, construction holds the last position. 

The DFAB house pioneered the world’s first digitally planned and primarily robotically constructed residential building. Universities, researchers, and industry professionals spent four years developing the machinery and methods that crafted the DFAB house. This architectural laboratory displays the potential of Digital FABrication in the notoriously archaic construction sector.

“Consider that in the United States between 1947 and 2010, agriculture achieved cumulative real growth in its productivity of 1,510% and manufacturing 760%. Construction managed only 6%. U.S. construction-sector productivity is lower today than it was in 1968” -Marketwatch 2017

Globally, construction lacks 1.6 Trillion dollars of infrastructure investment every year, with 1/3 of this investment missing in North America. This number matters. Construction unites, shelters, and hydrates our people. It creates our workspaces, schools, energy, and production plants and has consequences far beyond itself. Project management and technological innovation are two crucial factors in fixing construction productivity.

5 novel construction methods used in DFAB house

McKinsey estimates that 5 – 10x productivity boosts are achievable for some parts of the industry by constructing buildings in a prefabricated manufacturing style. Researchers used automation in conjunction with prefabrication to build the top floors of the DFAB house – mirroring the offsite manufacturing process of cars. “Using the computational design model, the multi-robotic system fabricated and assembled the design. Each beam was gripped and positioned by the robot, then cut using a CNC-controlled saw. Following this, the robot then milled and pre-drilled all of the required holes for the connection detailing.” – DFAB

Spatial Timber Assemblies

 The structure was transported on a flatbed truck, craned into place, and wrapped in translucent spaceship insulation: aerogel. 

About 90% of firms using prefabrication report improved productivity, quality, and schedule certainty compared to traditional stick-built construction. The competitive advantage prefabrication has over traditional construction techniques is that laborious tasks such as installing electrical, insulation, and plumbing are completed in a centralized area. The factory system allows for increased automation, a more predictable, safe job site, and standardized techniques and equipment, potentially saving time and money. Imagine if you built your car on-site. Or your phone? What about your furniture? Damn it, Ikea. Jokes aside, prefab also has challenges, primarily involving transportation, assembly, and significant upfront investment. 
Digital planning involves transitioning from paper-based methods to online, real-time information sharing. The heavy reliance on paper for managing blueprints, design drawings, procurement, equipment logs, supply orders, progress reports, and punch lists worsens construction’s low productivity. Lack of digitization leads to delayed and fragmented information sharing, discrepancies between owners and contractors, and wasted data. Not to mention paper-based systems take more time.

Digitally managing and planning are potent strategies; equally as interesting is digitally constructing buildings. Computer aided design (CAD) allows architects and engineers to uncover the most efficient structure and rapidly iterate their designs. 

The 3D printed formwork of the DFAB ceiling is optimized using CAD models. The computer-generated a lightweight but structurally optimized structure. The ceiling displays the convergence of creativity and technology in this new building era. “The key benefit of 3D printing is that geometric complexity and customization do not increase production cost and time” – DFAB. 

However, this does not mean that production cost and time is low. This is a common misconception in the 3D concrete printing industry. If 3DCP companies are slicing costs in half, why don’t these firms share the receipts for their finished products? 

On-site In-Situ Fabricator

Since CAD modeling is already commonplace in construction, adopting robots like 3D printers and In-Situ Fabricators that operate from 3D models is a relatively small step away. The In-Situ Fabricator (IF) constructed the rebar reinforcement within the double curved wall in the DFAB house. The machine rolls like a tank and meticulously welds rebar on-site. IF interacts with its environment, responds to unforeseen changes, and optimizes the fabrication process without relying on human interaction. This machine possesses “cyber-physical” capabilities.

Entry into the Fourth Industrial Revolution

These Cyber-physical advancements are sprouting in the 3D concrete printing industry. Intelligent batch plants monitor their environments’ ever-changing conditions, humidity, and nozzle temperature and adjust the mix accordingly. Gantry systems are learning to detect wind shifts and correct the nozzle position while continuously printing. 
The explosive advancements of 3DCP have the same catalysts that enabled the creation of the DFAB house:

Display of industry progress by Vertico

University:

Institutions such as the Technical University of Texas, the Technical University of Denmark, RMIT, the Institute for Advanced Architecture of Catalonia (IAAC), and MIT are a few well-known investors. University of Arkansas was awarded a 3.5 million dollar grant to advance 3DCP.

 
Private competition:

Each of the 360+ 3DCP firms and 103+ printer manufacturers are ferociously innovating to assert themselves as the machine for the masses: big-name partnerships and government interest are speeding up progress. Get a full list of manufacturers as a member of the Automation Nation or in the course How to Print a House

40% of 3D-printed buildings worldwide were built in 2022— proving this field’s young and explosive growth.

100 home development in partnership with ICON and Lennar. 7 3DCP deployed, Georgetown TX
A critical enabler of 3DCP growth is reconfiguring regulations and building codes. Adopting a building code for 3D-printed structures is challenging because the thickness, height, speed, and material deposited can vary drastically. All 360 companies have unique methods and makeups. However, The International Code Council’s Evaluation Service (ICC- E.S.) approved Black Buffalo and ICON walls. Code compliance will save these companies the time and money of complying with unrelated but established codes. Furthermore, the International Organisation for Standardization (ISO) and the American Society for Testing and Materials (ASTM) are developing industry standards emphasizing structural and infrastructure elements. Standards are the bridge between conventional and digital construction (pun intended). 

If governments are serious about helping the environment, investing in advancing building codes and this technology is a great start. Construction is responsible for an estimated ⅓ of the world’s waste and 40% of carbon emissions… 

“To accommodate the largest wave of building growth in human history, from 2020 to 2060, we expect to add about 2.6 trillion ft2 (240 billion m2) of new floor area to the global building stock, the equivalent of adding an entire New York City to the world, every month, for 40 years.”- Architecture2030.org

In other words, we are building ourselves into a “carbon lock,” as the inefficient buildings we construct today will spill carbon for decades. 20% of greenhouse gas emissions in the U.S. come from heating, cooling, and powering our homes. If American home emissions were considered a country, they would emit more carbon than Germany. Germany has the fourth largest GDP on Earth.

WASP designers in Italy are attacking this problem by optimizing buildings to ventilate and insulate naturally. Their 3D printer deposited the dirt on site, and due to the nature of 3DP, the optimized structure was a breeze to create.

WASP building utilizes traditional ventilation technique

Energy efficiency is essential, but the most carbon-intensive part of a home is the construction of the building. The average life expectancy of an American home is only 40 years. More sustainable practices and permanent structures can mitigate the consequences of the tear-down and rebuild culture of the US.

Our construction habits have ripples on our infrastructure, environment, and society which makes digitizing and automating construction historical. BIM networks, prefabrication, and robotic home builders are propelling us into a more developed world. Upon leaving the DFAB house, I felt grateful to be one of the few standing at the precipice of a revolution, watching it unfold, maneuver and grow into the world around us. 

Works Cited:

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