The fires are out, millions of dollars are being pledged, and the political will is there to begin restoring Notre Dame. But the cathedral is not only an ecclesiastical building, it is also a cultural and UNESCO heritage site. Experts around the world are discussing the best way forward. What will it take to restore the iconic church? Should it be restored to what it was, or should it be changed?
The cathedral's stone vault protected much of the building's interior, but the lead-clad timber roof and the 19th-century Neo-Gothic spire have been destroyed. French Prime Minister Edouard Philippe has called for a new spire that is "adapted to the techniques and challenges of our era." What will that mean?
A 21st-century legacy?
Julio Bermudez, a professor in the School of Architecture and Planning at Catholic University of America in Washington, D.C., said those restoring Notre Dame will have to decide whether to leave a 21st-century mark on the building.
"So I think we could have this conversation [about] how far we want to replicate exactly what it was before, or ... should we have a different level of response that acknowledges today's time," he said.
One concern is the condition of the three massive rose windows in the cathedral. Virginia Raguin, a distinguished professor of humanities at the College of the Holy Cross in Worcester, Mass., who has written extensively about the windows in Notre Dame, said a worldwide team of experts will assess any damage, but only once the structural integrity of the building is assured.
"They will have to assess the integrity of the windows,” she said. “And then they will make a decision as to whether or not they can be stabilized in place, whether they need to be stabilized in place, how to stabilize them in place or whether they need to be taken and then solidified,'' she added.
Digital preservation
Karpali Krusche, associate dean for research, scholarship and creative work at the School of Architecture at the University of Notre Dame in Indiana, is an expert in historic preservation and has worked on the digital preservation of the Taj Mahal in India and the Vatican's Belvedere Courtyard. She said rebuilding Notre Dame offers a unique opportunity to learn how to prevent disasters.
"So it is going to be crucial to understand how can we protect these monuments for any kind of natural or man-made disaster or attacks that can happen to such iconic monuments around the globe," Krusche said.
Art history professor Kevin Murphy of Vanderbilt University in Nashville said the site is important even to those with no faith, so restoring its former beauty is paramount.
"Many people who aren't necessarily Catholic who go there and feel inspiration will want to have that sense of soaring spaciousness completely restored, regardless of the particular choices that are made about materials and style and those sorts of questions," he said.
Protection from catastrophe
Restorers will also have to decide whether to rebuild the roof with wood or with other materials. It might not be possible to re-create the massive oak beams that held the previous roof. And preventing another catastrophe is a key concern.
Kobi Karp, an architect whose firm has designed and built commercial and multi-use properties around the world, said that even if the roof is restored to its previous design, it will have to incorporate modern fireproofing and firefighting equipment.
"And I think that now we actually have an opportunity to take our knowledge in fire life safety to go into the truss system, so when we do resurrect this beautiful volume and space, we would be able to hopefully never, ever have to face this event again,'' Karp said.
Ecclesiastical heritage
Any restoration will have to consider the artistic and ecclesiastical heritage of Notre Dame. Nora Heimann, associate professor and chair of the Art Department at Catholic University, said Notre Dame is as much a symbol of hope as it is a symbol of France or of the Catholic faith.
"We see it as a symbol of courage, we see it as a symbol of human resilience, we see it as a symbol of ingenuity,” she said. “And for those of us among the community of the Catholic faithful, it stands for the endurance of faith against all obstacles. That it [the fire] happened in particular in Holy Week just adds tremendous poignancy to it."
Bermudez said that rebuilding Notre Dame is an act of faith, not only for the French but also for all humanity.
"This is now a human heritage in which perhaps the French have more responsibility than many,” he said. “But then all of us are part of this beautiful project of faith in our humanity and in our connection to something larger than we are."
French President Emmanuel Macron has said that he wants Notre Dame restored in five years — just in time for Paris to host the 2024 Olympics.
