Firefighters took swift action after flames engulfed Paris’ Notre Dame cathedral and focused their efforts on preventing the fire from reaching its famed bell towers in order to save the entire structure, fire officials said Wednesday. “The two towers are pillars which keep the entire building up,” a Paris Fire Brigade official said during a press conference about two days after a fire spread in the cathedral. “The second you lose the war of the belfry, you lose the entire cathedral. It would have been a domino effect from there on out.” First responders to the fire said the flames could have had a much worse effect had they not acted quickly and put in place equipment to prevent a collapse. Firefighters managed to save the main structure of the building, the towers and most of the relics and artworks stored in the cathedral in the nine hours it took to contain the fire, officials said. The cathedral’s noted rose windows are “in good condition,” through its stone supports are at risk, Gabriel Plus, a spokesman for the fire brigade said. Now, experts and firefighters inside the Notre Dame are assessing what needs to be removed to avoid further damage and surveying the building for any remaining hot spots. Fire officials did not have immediate information on reconstruction efforts, though they said the cathedral’s scaffolding and vaulted ceiling have been deformed through extensive heat damage. Support beams have been put in place to avoid further collapse of the structures, they said. As experts assess the extent of the damage, France’s government has issued a challenge to rebuild the Notre Dame’s spire, which collapsed in the fire. Prime Minister Edourad Philippe invited architects around the world to send in designs and ideas on how the spire should be rebuilt. The announcement comes a day after President Emmanuel Macron vowed to rebuild the Notre Dame “even more beautifully” within five years. Get The Brief. Sign up to receive the top stories you need to know right now. Please enter a valid email address. * The request timed out and you did not successfully sign up. Please attempt to sign up again. Sign Up Now An unexpected error has occurred with your sign up. Please try again later. Check the box if you do not wish to receive promotional offers via email from TIME. You can unsubscribe at any time. By signing up you are agreeing to our Terms of Service and Privacy Policy . This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Thank you! For your security, we've sent a confirmation email to the address you entered. Click the link to confirm your subscription and begin receiving our newsletters. If you don't get the confirmation within 10 minutes, please check your spam folder. Write to Mahita Gajanan at mahita.gajanan@time.com.<doc-sep>The fire that engulfed the Notre Dame Cathedral Monday, causing its roof and its 300-foot oak spire to collapse, was extinguished Tuesday morning. But the damage is severe: The fire destroyed almost all of one of the oldest surviving timber frames in Paris. Fortunately, the blaze left much of the remaining structure intact and stable. “The fire was really limited to the roof, and because it’s conceived structurally as a separate system, it can burn without affecting what’s underneath it to a large extent,” Kevin D. Murphy, a professor of art history at Vanderbilt University who has studied Notre Dame’s restoration in the 19th century, told Vox’s Jen Kirby. Officials are still uncertain about the cause of the inferno. But the cathedral, an 850-year-old exemplar of French Gothic architecture, was undergoing renovations, and officials say something may have accidentally ignited amid the construction. Even though there’s a lot for fire investigators still to unpack, fire experts say there are a number of explanations for why the cathedral was at risk and why, once the fire got going, it was so difficult to fight. To find out more, I called Thomas Gernay, an assistant professor of civil engineering at Johns Hopkins University who studies how fires affect structures. He described four big hazards that combined to fuel the destruction. Notre Dame hasn’t been in great shape for a while Built in the late 12th century, the cathedral was beginning to show its age. Pollution, weathering, and acid rain stained and pitted its walls and gargoyles. And there were conflicts over who should pay for its upkeep, delaying much-needed maintenance, like removing flammable dust or waxing the wooden roof structure to prevent it from drying out. That’s a big reason extensive renovations were underway when the fire broke out. The renovation process introduced new fire hazards Bringing power tools, electric lamps, and welding equipment in close proximity to a centuries-old building increases the risk of ignition. This is a hazard that comes with any kind of renovation at this scale, but it’s especially risky with a structure that wasn’t designed with fire prevention in mind. The scaffolding structure also provided fuel for the fire. “There are lots of construction fires. It’s quite a common situation,” Gernay said. “If you combine that with a building that was built at the time where there were no fire protection codes, that’s the situation we are observing.” There was a lot of available fuel to burn Though most of what we see from outside Notre Dame is stone and glass, much of the inside is buttressed by timber. Builders harvested more than 5,000 oak trees across 52 acres to build the beams, trusses, and reinforcements for the stone structure and to hold up the roof’s 200-metric-ton lead cladding. The trees themselves were three to four centuries old when they were harvested. The roof’s latticework used so much wood, it’s been nicknamed “la forêt,” or the forest. “The roof structure, for instance, is made of thick timber beams, which obviously can provide some of the combustible material and participate in the overall stability of the structure,” Gernay said. By Tuesday morning, it was clear that almost all of the interior wooden structure had been lost, but most of the stonework survived. The fire was difficult to extinguish because it was out of reach Much of the combustible material in Notre Dame was in its roof structure more than 100 feet off the ground. The cathedral’s spire reached up more than 300 feet. That means the fire was far from the firefighters when it ignited. “The hose streams could not reach the top,” Gernay said. “At the same time, it’s very difficult to access if [firefighters] wanted to climb up on foot because of the very narrow and winding steps. ... They could not really act efficiently to fight the fire at that stage.” And air-dropping thousands of pounds of water all at once on a burning, fragile building in the middle of a dense city would have been counterproductive. “It would be dangerous for structural stability,” Gernay said. “Any sudden loading like this could be the triggering point that triggers the whole [structural] collapse, and of course we want to avoid that.” Former firefighter Gregg Favre echoed this point on Twitter: Inside is a whole other problem. The primary option is large 2.5" fire hoses. These are heavy, difficult to maneuver and against a fire like this, largely ineffective. pic.twitter.com/5tt3yDUpSo — Gregg Favre (@GreggFavre) April 15, 2019 As far as we know, most relics and much of the art was rescued. However, The Guardian reported that some artifacts did sustain damage and others were lost. No fatalities were reported from the fire, but two police officers and one firefighter were injured. French President Emmanuel Macron vowed to restore the cathedral. “We will rebuild Notre-Dame,” he said. “Because that is what the French expect.” French billionaire François-Henri Pinault has already pledged €100 million to pay for its reconstruction. But builders will have to mind the delicate balance between preserving history and preventing future disasters. “Hearing that reconstruction is being proposed, that should give an opportunity to consider fire protection options for the structure so as to avoid another catastrophe of this magnitude,” said James Milke, chair of the department of fire protection engineering at the University of Maryland, in an email. There may not have been sprinkler systems and fire-resistant cladding in the 13th century, but they may be necessary to ensure Notre Dame survives. Yet even the best fire prevention techniques can only do so much for church prized for its antiquity. The same vaulted ceilings, wood framing, and classical building techniques that make Notre Dame so valuable also make it harder to prevent and fight fires. “A structure as large and old as this is difficult to protect from fire. The rooms are large and high with tons of exposed wood and flammable roofs,” said Peter Sunderland, a professor of fire protection engineering at the University of Maryland, in an email. “Consequently, there are many exceptions in fire codes for places of worship.” Notre Dame is a survivor Like the ship of Theseus, Notre Dame has suffered damage, repair, and reconstruction over the centuries. It was damaged by rioting Huguenots in the 16th century. It was nearly destroyed during the French Revolution as angry crowds sacked the building and decapitated statues. The cathedral has since withstood two world wars, including bullet damage during the Nazi occupation of Paris. The cathedral has also undergone numerous renovations in its history. Its bells were recast and restored in 2013. The recent fire, however, is a reminder that for this — and for every ancient monument — we still have to prepare for once-in-a-century events.<doc-sep>
From Bits to Atoms The world watched in horror Monday night while flames tore through the Notre Dame Cathedral in Paris. As fire consumed the roof and toppled its iconic central spire, it seemed as though the historic church could be lost forever — but it’s possible, thanks to cutting-edge imaging technology, that all hope may not be lost. Thanks to the meticulous work of Vassar art historian Andrew Tallon, every exquisite detail and mysterious clue to the building’s 13th-century construction was recorded in a digital archive in 2015 using laser imaging. These records have revolutionized our understanding of how the spectacular building was built — and could providea template for how Paris could rebuild. According to Wired, “architects now hope that Tallon’s scans may provide a map for keeping on track whatever rebuilding will have to take place.” One Billion Data Points In 2015, National Geographic profiled Tallon and his unique scanning process, highlighting his digital imaging of the Notre Dame Cathedral. For centuries, the only tools we had to measure medieval buildings and structures were primitive — strings and rulers, pencils and plumb bobs — but by turning to 21st-century technology, Tallon was able to tease out the secrets of this miraculous structure. “If I had texts at every point, I could look in the texts and try to get back into the heads of the builders,” Tallon said to Nat Geo. “I don’t have it, so it’s detective work for me.” For his scans of Notre Dame, Tallon recorded data from more than 50 locations in and around the cathedral, resulting in a staggering one billion points of data. Each scan begins by mounting the laser onto a tripod and placing in the center of the structure. The laser sweeps around the area in every direction, and as it hits a surface, the beam bounces back, recording the exact placement and surface of whatever buttress or column it landed on by measuring the time it took the beam to return. Every measurement is recorded as a colored dot, combining together into a detailed picture, like the color pixels of a digital photograph. Eventually those millions of dots form a three-dimensional snapshot of the cathedral, and the resulting images are meticulously precise; if the scan is done properly, Tallon told Nat Geo, it should be accurate within 5 millimeters. What Needs to be Rebuilt According to The New York Times, it took less than an hour for the fire to spread from the attic of the cathedral and engulf the roof, toppling the central spire. Construction on the cathedral began in the year 1163 and finished in 1345, according to an NYT piece about the history of the cathedral, and the wooden roof contained historic beams from the year 1220, all of which were destroyed by the blaze. Support for the recovery efforts have begun pouring in, with wealthy Parisians and companies pledging more than $450 million in donations to Notre Dame’s restoration. Despite the extensive damage, the NYT reports that most of the priceless artifacts and the stone structure of the cathedral remain intact — though only time will tell how long it’ll take to restore the beloved structure to a semblance of its former glory. READ MORE: The Notre Dame Fire and the Future of History [Wired] More on 3D scans: See the 3D Images Produced by the First Full-Body Medical Scanner As a Futurism reader, we invite you join the Singularity Global Community, our parent company’s forum to discuss futuristic science & technology with like-minded people from all over the world. It’s free to join, sign up now!