I am Anthony Frausto-Robledo, AIA, LEED AP, editor-in-chief at I assemble the monthly INSIDER Xpresso newsletter to help us understand emerging technologies (emTech) and the social forces impacting CAD industries like AEC and manufacturing.

This month we focus on Notre-Dame de Paris and its reconstruction efforts. Our Special Feature delves into how BIM is aiding the process and discusses project particulars like harvesting the oak from royal forests for the timber frame replacements. 

This month. In issue #30! 
  • Starter Course: The Top Five Must-Reads
  • Special Feature: Two Year In — Autodesk's Assistance to Notre-Dame in Paris
  • emTech: Emerging Technologies -- Sources of info on Notre-Dame de Paris reconstruction and restoration; plus AGP in France as an elite source for reality capture of historic buildings; digital twin providers in France, and reality capture tech, and more...!
  • The Briefing: Biggest CAD Industry News Last Month

Our 4th INSIDER Report was published on 26 July 2021. "INSIDER: Rising Stars — Five Tech Firms and their Impact and Innovations" focus on articles detailing five key AEC industry technology providers who are making significant noise in the industry. 

You can see all four INSIDER Reports here. We highly recommend these thematic reports for those who are not aware of them. 

The Xpresso Index and Glossary are still on the horizon. It has been moved back to early Q3, 2021 to align with other Architosh updates.
Starter Course

The Top Five Must-Reads

I've combed the Internet to find some of the most interesting, compelling, or controversial stories about the AEC and manufacturing industries, and the social and emerging technological forces at play on both. 

1 - 10 Architects: Advice to the Young   "Empathy is one of the biggest superpowers you can have, almost in any field, but especially in architecture." This advice is shared, among others, through a series of video interviews directed at the young in or considering architecture.   (Louisiana Channel)

Italian architect Renzo Piano (b. 1937) shares his advice to the young thinking of entering the profession of architecture. 

A Whose Who:  This video features advice from world-famous architects, including Renzo Piano, Frank Gehry, Kengo Kuma, Norman Foster, Bjarke Ingels, and others. The quote above is from Ingels, who takes quite a long time to make his point. Renzo Piano makes perhaps the clearest point of advice. Tatiana Bilbao shares a personal story about her discovery of the vastness of knowledge and culture and that the academic background of architecture falsely teaches us that we can understand everything but we can't.

Criticism:  While the various points of advice shared by 10 architects are interesting, none of them really reflected the dynamic changes happening in the profession today. Last month we shared a blog post by Scandinavian architecture firm Henning Larsen titled, "Three Paradigm Shifts that will Change the Profession of Architecture." That short read may be worth a second view. 


2 - "The Profession is in Dire Straits": GLUCK+ on the Future of Architecture and Design-Build.  This article is a Thomas Gluck interview from ArchDaily and is comprehensive about this role at the firm.   (blog: ArchDaily)

Interesting Comments:    "We feel very strongly that the profession is in dire straits, and we all need to do everything possible to restore the reputation of the profession. As architects, we have shied away from liability and have given up more and more responsibility, creating a spiral that only reinforces these trends. We at GLUCK+ acknowledge there are lots of ways of reversing this, but one we have embraced is to take full responsibility for the delivery of our projects from conception to occupancy. We stand behind our visions by guaranteeing their construction." 

Steve Jobs back in the spring of 1992 talking to students at the MIT Sloan School of Management. His advice to business school students at 15:30 in the video has big implications for the role of the architect in society. His advice aligns with Thomas Gluck and his firm's position with respect to design + build. 

Familiar Comments from Steve Jobs while giving a talk to MIT students back in the 90s made a sharp comment about the world of consultants versus the world of non-consultants. He says that "without owning something over an extended period of time...where one has the chance to take responsibility for one's recommendations, where one has the chance to see one's recommendations through all action stages and accumulate scare tissue from the mistakes they make and pick oneself off the ground and dust themselves off..."  In essence, what Jobs says in this video is coming in and making the recommendations and not owning the results is a fraction of the value and a fraction of the opportunity to learn and get better.

So GLUCK+ is operating like a manufacturing company—to use Jobs' thinking in this video—meaning they ultimately own the results of their own [design] recommendations as architects. 


3 -  CMU and MIT AI Researchers Present A New Method to Sketch Your Own GAN With A Pencil   Xpresso readers learned about GANs in the very first issue of Xpresso where we focused on artificial intelligence in the world of Architecture.  A GAN is a "generative adversarial network" and specifically is a type (or class) of machine learning. It's called "adversarial" because a "generative network" produces candidate solutions to a problem while a "discriminative network" evaluates these solutions. These two networks work in a back-and-forth manner like a chess match.     (Marktechpost)

Why This is Interesting?  This research is interesting because it asks the question of whether sketching can be used as a more practical means for generating new generative models? The research proved great efficiency but was only successful for a very limited set of drawings. Where this technique may point to eventually is the ability AI systems to respond to an architect to get closer to what they may be thinking by the architect inputting hand sketches. You can see GANs as applied in architecture and learn more about Natasha Bajc's work investigating them in the field of architecture here from Xpresso No. 1.  

4 -  Researchers launch architecture industry mental health survey.   This article is about a new survey launched by Australian researchers on the mental health of the architecture industry.     (ArchitectureAU)

A research group funded by the Australian Research Council in 2020 is looking deeply at the mental health of architecture professionals and students. (Image: Israel Andrade/Unsplash)

It's the Culture:  The article quotes the research leaders as saying: "Many believe that the mental health challenges we face originate from within the architectural culture — the workplace practices, norms, and attitudes that prevail within the profession and its education."

My thoughts: Every architect has their own opinion about the profession. The long hours and dedication attitudes over a drafting board have given way to long hours in front of electronic screens, all of which other studies are showing is harmful to people. There is so much more one could say about the late-night studio culture of architecture, but I will pause here. To read the full article click here. Australian architecture students and professionals are can participate in the research.  


5 - Is 3D printing the future of building homes?   This story gives a good overview of 3D printed housing, and particularly in the German market where not much has happened yet.    (Deutsche Welle

This house in Beckum, Germany, was created using printed concrete.  (Image: Guido Kirchner/dpa/picture alliance)

Big Picture?  German architect Waldemar Korte, says in the article that "we, as planners, have a lot more freedom with the concrete printer...we can really play around with the form." Without concrete forms and with this new technique more organic and free-flowing form-making is possible. 

That's not the only big point. Experts in these new 3D printing processes predict that progress in the technology could enable houses to be constructed cheaper by 3D printing than traditional construction methods in as few as five years' time. The large "learning by doing" process that contributes to Wright's Law will no doubt drive down costs at a predictable ratio for each doubling of cumulative total production. The reality is though, that some companies—and countries—are still at total production levels that number in single digits, like in Germany.

For other "3D printing news" see our emTech section below. 


Five More Stories

We are skipping the Five More Stories section and the "Member Access—(emTech) Section+" article this month. We will return to a more enhanced version in the near future. 


More (emTech) Below Our Special Feature
Our Sponsor
Special Feature

Two Years In—Autodesk's Assistance to Notre-Dame in Paris

BIM technologies are giving the most famous cathedral in the French capital a fighting chance to return to visitors in time for the 2024 Olympic Games.  


THE WORLD WATCHED IN SHOCK as Paris' most famous cathedral, Notre-Dame de Paris, was caught in raging flames on 15 April 2019. A fire had started in the attic, and this ancient landmark had no sprinkler systems to combat such an event automatically. Despite a series of human errors that delayed the French firefighters from arriving faster, in the end, the iconic cathedral, whose name in French is Our Lady of Paris, was spared, sans a beautiful spire and large sections of its wooden-framed lead roof. 

Notre-Dame de Paris, in raging flames on 15 April 2019, showing the nearly complete destruction of its wooden-frame lead-coated roof. (Gilbert Bochenek, CC-SA 4.0, Wikimedia Commons.)

Notre-Dame was actually under repair with steel scaffolding connected to its body. Much of this melted under the intense heat, adding to the complexity of restoring the cathedral. While the world responded with outpours of sympathy, multiple large global corporations made significant financial donations and offered technical services and assistance to the effort. Autodesk was among these companies, joining companies like Apple.

"Straight away, our CEO Andrew Anagnost felt very emotional about this situation, and we wanted to do something to help with the cathedral," says Emmanuel Di Giacomo, Autodesk BIM Ecosystem Manager for Europe. "In addition to our cash donation, we also thought we could help in the reconstruction, and we felt that BIM (Building Information Modeling) could certainly help to accelerate the process," he adds. 

"Straight away, our CEO Andrew Anagnost felt very emotional about this situation, and we wanted to do something to help the cathedral."

And acceleration was going to be an essential element in Notre-Dame's reconstruction efforts as French President Emmanuel Macron had declared that the restoration should be completed in less than five years, in time for the Paris summer Olympic Games in 2024. I asked Di Giacomo if, after two years in the project was on track. "Honestly, I think the project is on track," he says, noting that recently the reconstruction team had selected the trees that will ultimately become its new roof. 

After two years—and with a three-month pause in efforts due to the global COVID-19 pandemic—the Safety Phase is complete, and the Reconstruction Phases have begun. Critical to all these efforts are accurate recordings of what was there—something achieved with pre-fire and post-fire laser point-cloud scans—and an accurate BIM model to help in orchestrating the work. This is where Autodesk felt it could provide the most assistance. 

The Push for BIM

Autodesk had already created an amazingly detailed BIM model in Autodesk Revit before it announced its official patronage with the public establishment dedicated to the restoration of Notre-Dame cathedral. 

Notre-Dame de Paris, the BIM model inside Autodesk Revit software. The model was produced by a specialized team at Autodesk and is part of the company's technical assistance to the reconstruction. The company also contributed to the worldwide and corporate cash donations for the cathedral, which today total over 1 billion USD. (click image for larger view)

The BIM model creation was a challenging affair because Paris's most famous cathedral was never well documented in 2D drawings. Initially built in the 12th century, master builders primarily constructed buildings sans drawings, sometimes using miniature models from clay as guidance. And in the many centuries since its completion, there were never many official building survey-created drawing documents covering the entire gothic masterpiece. 

"When we started to work on the creation of a BIM model for Notre Dame, we partnered with a local company with specialization in point cloud technology called AGP," says Emmanuel Di Giacomo, Autodesk BIM Ecosystem Manager for Europe. "Working a full year on this model was a big challenge, but it led to a very positive outcome when it came time to meet with the EPRND (the French public establishment charged with the restoration and conservation of the cathedral)," says Di Giacomo. "We were able to show them how this BIM model would help them accelerate the construction process."

"When you look at the cathedral in pictures, it doesn't seem that big, but when you are on-site, it's huge, and it's completely distorted as you can imagine because it has been evolving through the centuries."

While Autodesk achieved building and contributing an accurate BIM model to the reconstruction process, the effort proved challenging in many surprising ways. For starters, Notre-Dame is a massive stone structure measuring well over 1300 feet from end to end, and given its size and degree of detail, the modeling efforts are enormous. "When you look at the cathedral in pictures, it doesn't seem that big, but when you are on-site, it's huge," says Di Giacomo, "and it's completely distorted as you can imagine because it has been evolving through the centuries."

The Notre-Dame de Paris BIM model in this image shows elements used as part of the construction process, such as the low structures in the main court (right side). BIM is useful to construction logistics planning. 

"We have been using lots of [Revit] families and adaptive components," says Di Giacomo," who adds there were more than 12,450 objects that were created for the BIM model. And of the 180 vaults in the cathedral, what the teams have learned as reality capture cloud technology was deployed to record what is there, they now know that every single vault is different, even if ever so slightly. 

While the French architects charged with the restoration of this Gothic masterpiece are far less interested in digital technologies than the elite Revit team Autodesk has provided to the project, in the end, the EPRND and its teams know they are gaining three primary benefits from the BIM model. 

The Notre-Dame de Paris BIM model in this image shows the main component blocks of the structure, isolating the roof (top) and spire, which largely burned down, from the main body of the nave with supporting walls, buttresses, and vaults (middle), and then the base of the building and interior columns (bottom). 

"First of all, the BIM model can help with site logistics, like knowing where to place cranes and where workers and materials enter the site," says Di Giacomo. "Next, the BIM model can help with construction logistics and quantity takeoff," he adds, an activity that involves planning and sequencing the construction work and dealing with safety and risk management. And finally, the BIM model is used for collaboration when harnessed in Autodesk's BIM 360 collaboration platform, helping streamline the workflows between planning, construction, and exchanges between build and owner stakeholder groups. 

The Spire and the Roof

The horrible fire that engulfed the Paris landmark back in 2019 caused the nearly complete loss of the wood timber roof structure and the total loss of the wooden spire designed by 19th Century master architect Eugène Viollet-le-Duc. While there was much debate and speculative design visions for the future of the great cathedral—including an international design competition for a new spire that French President Emmanuel Macron later abandoned—on 9 July 2020, the decision was made to rebuild a spire identical to the one that existed.

The Notre-Dame de Paris spire was completely destroyed in the fire. It was the one element that was not modeled in Revit, but rather Autodesk Maya software. 

The ornate le-Duc designed spire is the one element of the BIM model that was not modeled in Revit. Instead, Emmanuel Di Giacomo says, "the spire of the cathedral was modeled with Autodesk Maya." 

The cathedral roof—one of the significant areas of damage on Notre-Dame—is constructed of wood timbers with lead roofing. "One of the biggest parts of the reconstruction is the roof itself," says Di Giacomo. "They have already chosen the trees," with the selection process initiated in January of this year. More than 1,000 French oaks from over 200 French forests, both private and public, are destined to replace large roof sections and replace le-Duc's beautiful spire. The oak for the spire itself was felled back in March in a once royal forest in the Loire region.

The French oaks from royal forests all over France are a source of large oaks. (Romain Perrot, CC-SA 4.0, Wikipedia Commons).  Les chênes de la Forêt de Bercé

To keep on schedule, all the French oak needed for the project needed to be cut by the end of March to avoid tree sap and moisture entering the wood fibers. The lumber is now drying in facilities and will do so for 18 months. 

BIM to Digital Twin

With the selection of the trees on schedule and other elements of the project on track, things look promising for Notre-Dame's restoration schedule. Every element may not be complete by the 2024 Olympic Games, but the cathedral itself has a good chance of re-welcoming visitors come summertime in 2024. 

I think the first subject we wanted to learn more about focused on the modeling capabilities of Revit, in the context of a historical monument; we have definitely learned where the software is and what we should do next. This was very exciting and meaningful for us.

Having a BIM model will help the restoration teams hit that Macron deadline as they solve numerous issues involved with making the cathedral safer from such fires in the future. Di Giacomo says that the reconstruction team wants to use all the cavities in various parts of the cathedral to run all the wiring and fire-protection systems. The group may use BIM to implement that process. 

The BIM model, of course, can become a critical component of implementing a Digital Twin of Notre-Dame de Paris after reconstruction. "We told the Archbishop that they could use the BIM model to connect with sensors to help protect the future of the cathedral," he says. Di Giacomo says that Autodesk is trying to convince the multiple parties that have a stake in Notre-Dame to do this. "If this does happen," he says, "there would be an official tender because when a contract is over 100,000 Euros in France, they must make a tender." 

The Notre-Dame de Paris BIM model was entirely modeled in Revit, including the complex rose windows, with the exception of the spire. 

While Autodesk has new Digital Twin software offerings, like its new Autodesk Tandem platform, Di Giacomo says that several French and European companies would likely pursue such a tender. "There are companies like VINCI Facilities’ TwinOps of France and CapGemini with Reflect IoD or ENGIE’s BLM, each of them top companies with solutions built on Autodesk Forge," says Di Giacomo. 

Lessons for the Future

I asked Di Giacomo what Autodesk has learned through their work in building the Notre-Dame BIM model. "I think the first subject we wanted to learn more about focused on the modeling capabilities of Revit," he notes, adding that "in the context of a historical monument, we have definitely learned where the software is and what we should do next. This was very exciting and meaningful for us."

"We also learned a lot about the performance of the software as we worked on the building," he says. "This model is huge at nearly 1 gigabyte of data, and we were surprised to find that Revit was reacting pretty well to such a large complex model." Di Giacomo adds that there are things particular to old monuments, old architecture that gives them ideas for the future.

And as for the future of Our Lady of Paris? With good luck and a reconstruction teamed benefitting from key Autodesk BIM technologies, the summer of 2024 may see Olympic attendees witnessing more than just record-breaking athletes but the reconstruction of an ancient masterpiece of architecture in record time. 


Editor's Note

This article mentions several BIM and digital twin companies. See our Curated EmTech section below for more information on these as well as the Notre-Dame cathedral restoration in general. 

To learn more about Autodesk Revit BIM solutions visit here. 


Our Sponsor

Curated content: Emerging Technologies and their potential impact on CAD-based industries.


More on Notre-dame de Paris - Reconstruction

This article in Science from last year reviews how scientists are leading Notre-Dame's restoration. This is an excellent, in-depth article focused on scientists from the Historical Monuments Research Library (LRMH) in France, who entered the building just ten days after the terrible fire destroyed its roof and spire. What they found is largely detailed in this article by Science

There are several sources online to keep track of the reconstruction efforts at Notre-Dame de Paris. Friends of Notre-Dame de Paris is an official 501(c)(3) organization in the United States and is leading fundraising efforts for the cathedral's restoration. This is an excellent website to keep track of progress and they have excellent photos of the reconstruction effort. 

The Spire Debate: General vs Architect

One interesting development, post-fire, was the public squabble between the chief architect of Notre-Dame, Philippe Villeneuve, and General Jean-Louis Georgelin, who Macron put in charge of overseeing the rebuilding. Villeneuve was vocal publically that the spire should be rebuilt as-is while Macron had initially announced an international design competition for its replacement. In the end, the French government sided with the chief architect's views after General Jean-Louis Georgelin had shocked the public by stating in an outburst about the issue, "as for the chief architect, I have already explained that he should shut his mouth." 

Measuring Notre-Dame: Point Clouds

Emmanuel Di Giacomo of Autodesk told us that they worked with France-based AGP, "a local company" he says. AGP stands for Art Graphique & Patrimoine. The Paris-based company, founded in 1994, is passionate about heritage architecture and its preservation with expertise in archeological surveys using advanced digital tools. 

AGP provided high-definition 3D point clouds for Autodesk. It likely also deployed its expertise in aerial photogrammetry to capture the top of Notre-Dame and its surroundings. There is a specific page on its website focused on Notre-Dame de Paris. Here is a link to it in English

AGP has a talented team of architects, engineers, stonemasons, and restorers, historians, and archeologists. AGP's capabilities make them a global leader in Scan to BIM processes and the accurate recording and measurement of historic structures—all invaluable to architects and their teams worldwide. There is an excellent video (French language) discussing their partnership with Autodesk. (link here). 

It should be noted that in my research for this article, I also learned that the late professor Andrew Tallon, of Vassar College, Columbia University, used laser scanning to capture the domes and columns inside Notre-Dame cathedral. Tallon had captured over one billion points of data and a CBS This Morning episode noted Tallon's work shortly after the fire.

BIM to Digital Twin

Scan to BIM technologies like Autodesk's ReCap Pro software is invaluable in restoration projects like this or the recording and surveying of historical ancient landmark buildings. However, once an accurate 3D BIM model has been created, its use as an asset for a "digital twin" of the real building adds even more value to the BIM model. 

A contract for long-term digital twin operations would need public tender and work through only French companies. However, Autodesk now offers its Tandem digital twin platform which we wrote about on Architosh. 

Di Giacomo mentioned VINCI Facilities TwinOps in France and CapGemini with Reflect IoD or ENGIE's BLM—all of these companies built on Autodesk Forge platform technologies. And Autodesk Tandem is Autodesk's own digital twin platform. 

More Reality Capture Items

Notre-Dame's reconstruction efforts utilized the advantages of reality capture technology and software. There are multiple solutions on the market, including but not limited to: Other interesting companies include Agisoft Metashape, Meshroom, 3DF Zephyr, and PhotoModeler

Robotics in AEC News

We have a few more items involving robotics news for AEC. 'QuicaBot' is a robot that works alongside building inspectors, aiding in the process of complex inspections of construction sites, offering assistance and boosting safety. (see below)

A robot can help a building inspect take precise dimensions, observe situations where the human inspector cannot access or there is danger, and record and hold data, among other benefits. 

Steven Beites, an associate professor at the McEwen School of Architecture and principal at Studio Kimiis in Toronto, Canada, heads a team exploring new methods of construction utilizing robotics. His particular focus is on developing a cable-driven parallel robot for large construction projects. 


What's Cooking: Future Xpresso Features

Our next issue of Xpresso (#31) has, again, several possibilities. We will share more details on Architosh in the announcement banner on the top page of the site as we get closer.  Stay tuned! 
The Briefing

Biggest CAD Industry News Last Month

(the biggest news and features in July)

INSIDER: Shapr3D is Bold on Apple and CAD Dominance This feature is part of our 4th INSIDER Report series and covers this exciting award-winning CAD developer who is focused on moving to Apple's ARM-based chip Mac platform as their next expansion move, after obtaining triple the number of users as Onshape on just the Apple iPad platform.    [7-10 min. read]  (Architosh). Recommended for MCAD users and industrial designers. 

INSIDER: The Fourth Revolution—How Spacemaker AI Optimizes Architecture Development   Part of our 4th INSIDER Report series, this feature gets behind the "origin" details of Spacemaker AI and how the company can bring "over-the-shoulder AI" into the design processes of more architectural professionals.    [7-10 min. read]  (Architosh).  Recommended for all AEC folks interested in AI and machine learning. 

INSIDER: Remote Work Has A New Partner in Varjo VR-3 and XR-3 Headsets
Varjo is one of the most impressive technology companies in the world and this feature goes deep on their latest gear and their newest announcements related to virtual teleportation.   
 [5-8 -min read]  (Architosh).  Recommended for all readers of Architosh! And VR/XR folk! 

BIM News: Graphisoft to Merge with Data Design System of Norway

This was big news at the tail-end of July. Two Nemetschek Group daughter companies are merging to help bring more unified MEP BIM processes into the Archicad BIM platform.     [3-6 min. read]  (Architosh). Big BIM news! 

Autodesk Tandem: Digital Twin Platform Now Available
Autodesk's digital twin platform offering launches officially and is now open and available.      [3-6-min read]  (Architosh).  
Recommended for all AECOM readers. 

Nemetschek's ALLPLAN and SDS2 Join Forces—Merge Structural Solutions
The Nemetschek Group continues to merge daughter companies to expand globally and offer more concentrated expertise across a globally expanding user-based.   [3-6-min read]   (Architosh)  Recommended for BIM professionals

End Note
Remember you can sign-up for architosh INSIDER Xpresso here -- a unique CAD industry newsletter with a special focus on emergent technologies (emTech) like AI, ML, robotics, 3D printing, AAD, computational design, and smart cities tech.

As we move forward, our format will evolve but will aim to focus on emTech in AEC and MCAD. We welcome your suggestions (

To see Past Issues visit this link here.  (sign-up for the newsletter here)

Anthony Frausto-Robledo, AIA, NCARB, LEED AP

This is a free newsletter and companion publication to 
Architosh is subject to conflicts of interest when we write about CAD/AEC/MCAD/3D software/hardware and other related tech companies in the market. In the interest of disclosure, we encourage readers of this newsletter and the Architosh website to visit our Ethics page where we maintain a full list of Held Securities and discuss Our Disclosures. 

This statement and the intent of this section is consistent with Architosh's Disclosure statement on our Ethics page here.  [This rewritten section deprecates all other instances of this section for past issues of the newsletter.]
Architosh on Facebook
Architosh on Twitter
Architosh on LinkedIn
Architosh Readers Group on LinkedIn
Copyright © Architosh, INSIDER Xpresso, All rights reserved.

Want to change how you receive these emails?
You can update your preferences or unsubscribe from this list.