Hours after a massive fire consumed Notre Dame Cathedral, gutting the roof and engulfing the famed spire, French President Emmanuel Macron pledged to rebuild the historic church.
“We will rebuild it together. It will undoubtedly be part of French destiny and our project for the years to come,” Macron said Monday.
READ MORE: Historian explains why the Notre Dame cathedral means so much to the world
Fundraising efforts have also kicked off to restore the 856-year-old building, with a number of companies, countries, and billionaires pledging hundreds of millions of dollars.
Investigators are already assessing the extent of the damage and although it’s still too early to know what needs to be rebuilt, experts on Tuesday warned it may likely take decades to restore the cathedral, rich with European Gothic architecture.
WATCH: France’s Macron says ‘we will rebuild’ after Notre Dame burns
Is it possible to save the famed cathedral?
The main part of the cathedral, along with the famed stained-glass windows and bell towers, have been saved from the destruction, according to French authorities. But they warned parts of the cathedral could still be at risk of collapse.
Peter Sealy, landscape and design lecturer at the University of Toronto, said he has “no doubt that it will be rebuilt.”
“It will not lack resources for this construction, unlike other heritage projects,” he said. “It will take an immense amount of time and resources and it’s still too soon to know what it will entail.”
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Sealy referred to Notre Dame as a living artifact, which has to continuously be worked upon and evolved over history.
“This is perhaps the darkest moment in history, but we should really think of it as a living, evolving organism, which will certainly be reborn, Phoenix-like from its ashes,” he said.
Architectural historian and broadcaster, Jonathan Foyle, told CNN the building is most likely salvageable.
“Notre Dame is not a building that has been fossilized in time. It has not remained static since the early 13th century,” Foyle said. “It’s lived through wars, it’s lived through reformers, and this will, I think, prove to be another episode.”
He told CNN the first step to restoration involves figuring out what is recoverable and how to prevent further damage. For example, providing a temporary cover to prevent rain damage.
French authorities will then need to understand how the medieval cathedral was constructed, he said.
“The stripped roof and upper masonry will reveal aspects of the building’s history which probably haven’t been understood,” he explained. “Notre Dame has virtually no building records. We know (that construction) started in 1163 and was basically completed by about 1240, but there are no building accounts,” Foyle told CNN.
WATCH: The glorious and tragic history of the Notre Dame Cathedral
He said France will have to hire archeologists and specialists from all over the world to understand how to rebuild the building.
France’s Education Minister Jean-Michel Blanquer, put out a call on Twitter Tuesday, asking for “stonecutters, carpenters … roofers, sculptors,” to help rebuild Notre Dame.
The head of a French lumber company, Sylvain Charlois, told FranceInfo radio that rebuilding the cathedral will “surely take years, decades even” and will require a lot of wood.
The framework for Notre Dame cathedral is called a forest because it required many trees to build it. The structure featured wood beams made from trees that were believed to have been cut down as early as the year 1160.
READ MORE: Notre Dame cathedral’s age, timber structure likely made fighting the blaze tougher
But Bertrand de Feydeau, vice-president of the Fondation du Patrimoine, said France no longer has trees big enough to replace the ancient wooden beams and the cathedral’s roof cannot be rebuilt exactly as it was before the fire. He said the restoration work will have to use new technology to rebuild the roof.
Keep Notre Dame the same or rebuild with a modern twist?
Another question that may play into reconstruction, is whether to replicate the past or add a modern 21st-century touch.
Notre Dame has already gone through significant changes since it was first built in the 13th Century. The spire that collapsed Monday was restored in the 1840s and made taller and more elaborate than before, Sealy said.
“It was rebuilt and embellished and changed quite a lot when it was re-erected in the 1860s. So it’s also a 19th-century building,” he said.
Stained glass windows that had been in the church since its construction were replaced during alteration efforts over the next two centuries, as both Louis XIV (the Sun King) and Louis XV went about modernizing the building in a more classical style.
Windsor Castle was restored after a massive fire
In 1992, a massive fire tore through Windsor Castle, home of Britain’s Queen Elizabeth II, damaging more than 100 rooms including the vast medieval St. George’s Hall.
Repairs to the oldest and largest occupied castle in the world began immediately after the fire and work was completed by Nov. 20, 1997. The repairs cost around US$48 million.
Architects who restored Windsor Castle said France can be reassured Notre Dame can be restored and even offered to help.
“In the initial stage, the most difficult question is how much of the standing structure can be consolidated and retained and how much of it might need to be taken down and rebuilt,” Francis Maude, an architect at Donald Insall Associates which led the restoration of Windsor Castle, told Reuters.
“The roof, I’m assuming, is oak and there’s plenty of oak available, including sessile oak which is long, straight-stemmed oak trees that they will need for these sort of projects,” he said.
How much will it cost to rebuild?
The cost of a likely multi-year restoration project could itself take a year to become clear, industry experts said.
“It is really going to be up to the French state and benefactors to help to restore and rebuild this,” Robert Read, head of art and private client at Lloyd’s of London insurer Hiscox told Reuters, adding it could take up to 20 years to restore the cathedral.
“The scaffolding costs are going to be enormous, actually securing the building is going to be enormous. The cost of renovating the (British) Parliament is a similar sort of number,” Read said.
The cost of repairs and upgrades to the neo-Gothic fronted parliament building on the banks of the River Thames has been estimated at up to $8 billion.
— With files from Global News’ Amanda Connolly, Reuters and the Associated Press