The various obstacles to the progress of the Notre-Dame reconstruction site - unsuitable health protocols, undersized workforce of the public establishment responsible for collecting funds - did not discourage the ardor of the Compagnons du Devoir who should keep the schedule for securing the cathedral vaults.
In the nave of the cathedral, huge scaffolding supports a working floor, some thirty-three meters high. It is in this space that craftsmen bustle about supporting the sexpartite vaults of the building, each resting on six pillars.
This “timbering” of the parts damaged in the April 15, 2019 fire was launched in March 2021: several half-hangers, strictly conforming to the shape of the vaults, and each weighing more than 1.6 tons, have already been installed.
"This is a traditional technique, implemented with modern tools," specifies Philippe Villeneuve, chief architect of historical monuments in charge of Notre-Dame.
It is moreover the same system which will make it possible to resuscitate the vaults which have collapsed: For these, "the hangers were made based on very precise digital readings of the building made before the fire," explains Philippe Villeneuve.
And he recalled that the vaults disappeared at the crossing of the transept due to the fall of the spire. Without the spire, built in the late 1850s, “they would have withstood the fire perfectly. The vaults demonstrated what they were invented for: to prevent cathedrals from collapsing after a structural fire.”
Built of spruce wood in Jarny (Meurthe-et-Moselle), the half-hangers were inserted into the monument through high window openings from which the stained-glass had been previously removed.
A securitization that is “unprecedented in its scope” and which “will be completed as planned this summer,” said General Jean-Louis Georgelin, president of the public establishment responsible for the restoration of Notre-Dame de Paris.
It remains to be seen whether this will be enough to meet the schedule set by the President of the Republic, who intends to reopen the emblematic building of Paris for worship in 2024.