Technology developed in Pittsburgh preserves world-famous places for future generations
By Hannah Frances Johansson
NewsWorks Lab staff writer
Frank Lloyd Wright’s Fallingwater, a modern house tucked into the woods of Fayette County, receives the highest standards of care in the field of historic preservation as a UNESCO World Heritage site.
But no one can predict its condition 100 years from now. In Paris, the Notre Dame Cathedral survived the better part of a millennium before it burned in 2019. In Syria, conflict destroyed much of the ancient city of Aleppo.
“God forbid” a disaster strikes Fallingwater, said Touf Hassoun, president and CEO of Carnegie-based architectural science firm CASE Technologies. “I don’t even want to think about it because it would really upset me, to be honest with you.”
From a first-floor office near East Main Street, Hassoun and his team are assembling the most intricate and exact model of Fallingwater to ever exist, using laser technology to create its “digital twin.”
Used in historic preservation, digital twins serve as a roadmap for future architects to restore structures and sites, precisely, no matter what happens to them physically. The technology has roots in Pittsburgh where a former Carnegie Mellon University doctoral student developed critical software, and technicians like Hassoun are putting it into practice.
The advent of Fallingwater’s digital twin falls on the 90th anniversary of the site’s construction. Wright designed the house in 1935 as a weekend home for his clients, the Kaufmann family, who owned Pittsburgh’s defunct Kaufmann’s department store
Since then, the structure has changed. The building underwent a massive reconstruction project over the past three years to improve waterproofing, repoint stones and replace crumbling concrete.
Fallingwater’s digital twin looks like a hyper-realistic video game. The balconies overhanging the waterfall, for example, bow at the same angle as in real life.
“We felt that it was really important to faithfully represent those existing conditions,” said Mark Dietrick, a director at CASE, as he demonstrated the model.
Toggle the time bar inside the gaming engine used to render the final product, and light from the windows appears to stretch or shrink, reflecting date and time references built into the model. Users can also turn lights on and off, illuminating swaths of stone flooring.
“It is georeferenced, so this is very real,” Dietrick said.
Digital twins
Like artificial intelligence, digital twins represent a new frontier of technology with transformational potential. Digital twins are navigable, digital models of objects, places or systems, augmented with real-time data from sensors in the field.
Since NASA defined the term “digital twin” in 2012, the technology has expanded beyond aerospace into areas such as biomedical research, climate science, manufacturing, defense, energy and urban planning, according to the National Academies of Sciences, Engineering, and Medicine.
In August, Target announced Proxima, a digital twin of a portion of its supply chain. The National Science Foundation awarded nearly $5 million to create digital twins of the world’s coral reefs for conservation. Digital twins of cancer patients help drive research and clinical decisions.
Industry analysts valued the 2025 digital twin market between $18.9 and $28.9 billion, and predict it will expand by an annual average of 30% to 40% over the next several years.
In the field of historic preservation, the interest in digital twins keeps growing. In April, National Geographic reported the Titanic has a digital twin. So does the Italian city of Venice. A digital twin for the recently restored Notre-Dame in Paris is in the works.
Preservation relies on a degree of speculation, said Justin Gunther, director of Fallingwater. Sometimes the reference is an old photograph or a letter. Combined with primary sources, an advanced technological record such as the one CASE has created “takes preservation to a whole other level,” he said.
Fallingwater’s twin
In high school, Gunther made the pilgrimage to Fallingwater from Virginia, where his drafting teacher kept a color pencil drawing of Wright’s iconic home pinned above his desk.
“Everyone sort of knows that iconic view of the house floating over the waterfall,” Gunther said. “I expected sort of this grand architecture. But then, once you get there, you realize how Wright really brought the house to a human scale, and an intimate scale.”
For many students across the world, a pilgrimage like Gunther’s remains out of reach. The digital twin could broaden the accessibility of the site in a kind of reverse teleportation: Rather than bringing the students to the site, the site is beamed to them
“You can still learn a great deal from being able to navigate in a virtual space,” Gunther said.
For now, the twin lives in a virtual cloud, inaccessible to the public. Eventually, the Western Pennsylvania Conservancy, which has owned Fallingwater since 1963, would like to make a version available for educational purposes.
Day-to-day, the Conservancy also plans to use the twin as a digital archive, a database for the art and furniture collections on display, and as a repository for more technical information.
“We have the physical filing cabinets in our archive storage building, but now we’ll also have the virtual filing cabinet in a virtual model,” Gunther said.
When sensors are installed and connected to the model, the Conservancy can use the twin to make remote decisions about when to intervene, if, for example, the flow of the waterfall becomes too strong, or the humidity is too high.
In the future, the model also could be used to 3D print exact replicas of damaged structures, Gunther said.
Natural materials
Hassoun, the CASE executive, said he admires the finer things in life, like wine, golf and marble.
“Ever since I was born, I’ve always loved limestone, marble and granite,” he said, “because they come from the earth, and that’s how they built things in the old days.”
A couple of years ago, on a drive through Italy — from Volterra to Florence — with a colleague, Hassoun articulated his bucket list of buildings for which he wants to create digital replicas: Vatican City, the Palace of Versailles in France, the Egyptian pyramids and, of course, Fallingwater.
CASE has so far generated hyper-realistic models for clients around the world, including the town of Volterra, Italy, museums in Paris, and a chateau in Normandy. In the Pittsburgh area, Brownsville borough hired the company to scan historic structures, including its old train station.
In September, CASE will present its digital twin of Fallingwater at an industry conference in Las Vegas, as part of an immersive exhibit complete with sounds of birds and water.
Laser measurements
If Hassoun is the brawn of the operation, then Dietrick, a wiry guy with big eyes, is the brain. Dietrick explained how the model was created.
First, a football-sized LiDAR unit on a tripod captures a 360-degree scan of its environment.
LiDAR stands for Light Detection and Ranging; it is a method for measuring distance using lasers. The distance, calculated by recording the time it takes for a laser to hit an object and return to the scanner, generates a point in space. Taken together, many points paint a three-dimensional picture.
The Fallingwater scan consists of 6.8 billion points. Each point is less than 2 millimeters apart, Dietrick said. That accuracy far exceeds traditional modeling with measurements taken by hand.
Following multiple LiDAR scans, Dietrick imports the data into software called ReCap that figures out where the points overlap and stitches the scans together.
Although LiDAR has been around for decades, a former CMU doctoral student dramatically improved its use in architecture when he created software that weaves LiDAR scans into images, automating what was once a more laborious process. This software became ReCap.
From ReCap, Dietrick imports the newly woven image into modeling software, and then he uploads that into a video-game engine, where a user may pan around various spots on the site and fly over the structure.
Some details are difficult even for the lasers to capture. Vegetation, for example, moves. As Dietrick panned around the Fallingwater virtual space, he pointed out a mossy rock wall that took hours of painstaking work to create.
“This gets down to a painting level of detail,” he said.
‘Lord of the Rings’
Before Aaron Morris created the software that later became ReCap, he stitched laser scans together manually in the field while developing robots to survey mines in dangerous, remote conditions to map inaccessible places or to rescue workers.
“I took those scans off that robot and just started to stitch them together live, so the robot could have a map,” he said.
Because of this, he spent lots of time underground.
“One of my favorite mines to go into was limestone,” Morris said. “They’re fascinating; it’s like ‘Lord of the Rings.’”
Limestone mines are held up inside with pillars of rock, as big as trees, and are sometimes used for storage.
“When you went down there, you’d see those pop-up carnival rides that come out in the summer,” he said.
A lot of his research had less to do with robots, and everything to do with digitizing the environment. A year after graduation, Morris created a business called Allpoint Systems where he developed the software that would contribute to ReCap.
In 2013, Morris sold Allpoint Systems to San Francisco software giant Autodesk, which produces some of the premier architecture and engineering software in the world.
These days, Morris is fascinated with the combination of artificial intelligence and digital twins.
Artificial intelligence
John Vickers serves as director of Louisiana State University’s digital twin facility, dedicated to studying and developing them. He is credited, along with others, for pioneering the concept of a digital twin, and finds their applications for historic preservation enamoring.
“I’ve been to the Louvre maybe half a dozen times, and it’s almost like I start over… every time I go,” he said.
The number of objects on display at museums around the world is a mere fraction of their archives. The Smithsonian, for example, displays less than 1% of its collections at any given time, according to a 2018 press release. Through a digital twin, these museums could display everything that does not fit into their physical collections.
“I probably won’t get to go again… you know, at my age,” Vickers, 67, said. “But if I could visit it digitally, anytime, and see many, many, many more things…”
Vickers worked at NASA for 40 years before joining LSU earlier this year. In the 1990s, NASA’s management motto was “faster, better, cheaper.” In some cases, it took up to four years to build a rocket engine, Vickers said. A digital twin of a factory or lab could save resources by moving trial and error from the physical world to the virtual world.
“Someday in the future, we will not do those [physical] experiments,” he said. “That’s so hard for people that are in this business to grasp.”
One day, artificial intelligence will navigate digital twins for us, Vickers said, bridging the physical and virtual worlds. The combination will become, essentially, an operating system.
“One of these days, the CEO will sit down in front of a mammoth computer screen, and an artificial intelligence person — like Alexa, Siri… that avatar of a person — will stand up and give the entire integrated picture of that enterprise,” Vickers said.
Stimulating awe
A virtual Fallingwater will never replace the multisensory experience of visiting the home in person, Gunther said.
These days as director, his journey to the site might seem more habit than adventure, but he still recalls how that first visit imprinted on his brain.
“You’re smelling the decay of the leaves, and you’re feeling the cool air of the stream, and you’re hearing the water and seeing this really intensively beautiful thing,” he said. “You’re never really going to get the full visceral reaction without being in the space.”
Still, he hopes the digital twin will stimulate a kind of awe that drives people to visit.
NewsWorks Lab is a public-benefit company owned by Trib Total Media to produce high-impact, accountability journalism as a free, open-source resource. You may find more information at NewsWorksLab.com.
Copyright NewsWorksLab, LLC 2026
