Flames and smoke rise from the blaze as the spire starts to topple on Notre Dame cathedral in Paris, Monday, April 15, 2019. Image Credit: AP

PARIS: France will open the redesign of Notre Dame de Paris cathedral’s historic spire to international architects after Monday night’s catastrophic blaze that gutted the centuries-old roof and sent the towering spire crashing through the vaulted ceiling.

Tycoons, international firms, local authorities and individuals have promised financial and expert help — with a total of nearly €900 million ($1.01 billion, Dh3.71 billion) pledged by Wednesday.

“The international competition will allow us to ask the question of whether we should even recreate the spire as it was conceived by Viollet-le-Duc,” Prime Minister Edouard Philippe said.

“Or whether, as is often the case during the evolution of heritage, we should endow Notre Dame with a new spire that reflects the techniques and challenges of our era.”

New technology to rebuild a heritage masterpiece

Craftsmen built Notre Dame eight centuries ago. Now it may be up to robots to save it.

Engineers around the world said one observation was already clear: To return the ancient structure to its glorious past, builders will likely have turn to cutting-edge technology that many associate with the future.

Some of the technology that will be used to restore Notre Dame has already been on display. As a wall of orange flames roared across the cathedral’s roof Monday, and hundreds of firefighters mounted their counterattack, high-tech machines had already been brought to the fight.

Hovering in the air above the cathedral, a pair of Chinese-manufactured commercial drones equipped with HD cameras - the Mavic Pro and Matrice M210, made by DJI - helped firefighters position their hoses to contain the blaze before it before it destroyed the cathedral’s two, iconic belfries, according to the French newspaper Le Parisien.

In the crucial months ahead, experts say, some of that same technology will likely be used to return the 13th-century cathedral to a place that last year drew 12 million visitors.

One way to start, the experts said, will be to bring in other drones to survey locations inside the vast cathedral that are too dangerous or damaged for engineers to reach.

Another method for testing the cathedral’s integrity could involve robots, Hajjar said, pointing out that research is already underway for using climbing robots to inspect and repair steel bridges.

A popular video game also could provide another source of digital information about the Notre Dame. In a 2014 article in the Verge, Caroline Miousse - an artist who worked on the video game Assassin’s Creed - said she devoted two years to creating a model of the church that captured the inside and outside of the building.

Once engineers have a clearer sense of the church’s structural integrity, experts said, they’ll be able to design a suitable roof. They’ll have to decide whether to rebuild the roof framing with timber. If they don’t opt for a structurally engineered wood, which could reduce the roof’s weight and offer artistic freedom, engineers could choose to work with steel.

Though it would depart from the church’s original wooden roof, steel would allow engineers to use less material and be even lighter than wood, according to Gary Howes, COO of The Durable Group, a consortium of historic restoration companies.

Replacing what was lost may not be the biggest challenge, Howes said. Instead, he said, it will be marrying the old and the new

What are the challenges with rebuidling Notre Dame?

French President Emmanuel Macron told the nation he wants the work to be done within five years, a timeline that would have the building ready by the time Paris hosts the 2024 Summer Olympics.

That’s a breakneck pace for a project of monumental scale that will involve hundreds, if not thousands, of master craftsmen, carpenters, masons and others working inch by painstaking inch to restore the structure to its past glory, say experts.

Notre Dame is full of touches and flourishes that reinterpreted and remade the original Medieval structure for a new era. The spire, for instance. The nearly-300-foot adornment, which was made of wood, sheathed in lead and pointed to the heavens. But the spire was only added in the mid-19th century.

Experts said that just assessing the damage will take a year or more.

Among the most immediate challenges in the restoration is the roof. A temporary one will need to be installed to prevent further damage to the interior. Then there will be the question of whether the permanent replacement should seek to replicate the original.

The roof support structure was known as “the forest”, and each timber was hewed from an ancient oak tree. The actual forest where the trees were harvested is long gone, and many have noted this week that trees as old and tall as that are now uncommon, but planners could still rebuild with oak that closely approximates the original wood.

For a design element that few will ever see - the wood beams support a metal roof - there is no reason not to choose a lighter and less expensive replacement, said Flix Bulcourt of Paris’s ENS design school.

Measures to improve fire safety, he said, should also be implemented in a building that withstood centuries without a serious blaze, but would never meet today’s rigorous standards.

Pledges to rebuild Notre-Dame Image Credit: Graphic News/Gulf News

Why the Notre Dame was so neglected?

The state of Notre Dame’s disrepair had been evident for years to the Archdiocese, the steward of the cathedral. Until a few years ago though, according to 2017 reporting by Vivienne Walt for Time magazine, the government had kept private areas “from which the decrepit upper levels could be accessed” off limits. Here’s what Walt found in those upper stories:

“Here, the site seemed not spiritually uplifting but distressing. Chunks of limestone lay on the ground, having fallen from the upper part of the chevet, or the eastern end of the Gothic church. One small piece had a clean slice down one side, showing how recently it had fallen. Two sections of a wall were missing, propped up with wood. And the features of Notre Dame’s famous gargoyles looked as worn away as the face of Voldemort.”

There were debates about whether Notre Dame should charge visitors to fund repairs as St Peter’s Basilica in Rome and St. Paul’s Cathedral in London already do. But some in the French senate argued that this would effectively amount to a tax on a place of worship. The entrance fees were never levied.

The Friends of Notre Dame, a non-profit organised by the archdiocese, launched a campaign to raise more than $100 million for repair work. But this effort ran up against two obstacles. First, while regular churchgoers may contribute small amounts to collections, the French are steeped in state-mandated secularism and so regarded donations to religious institutions suspiciously. Secondly, they are heavily taxed, so they also expect the state to look after major cultural sites.

In the current predicament for Notre Dame, money, expertise, and time are the only solutions and the right ones for now.