Mapei's solutions for Notre-Dame de Paris

Mapei is proud to be part of the extraordinary restoration project of the Notre-Dame de Paris cathedral, which was hit by a serious fire on 15^th April 2019. Collaborating with the two companies Lefèvre and CCR (BALAS group), which were awarded the tender commissioned by the Rebâtir Notre-Dame de Paris Public Authority, the commissioning body, the company provided solutions for the restoration of the vaulted ceilings of the transept, the two wings of the transept and the central nave (Lefèvre) and of the choir (CCR).

The reopening of the Cathedral to the public is scheduled for 8^th December, on the occasion of the celebration of the Immaculate Conception, although not all operations will be completed.

For this project, Mapei put into practice its most advanced knowledge and skills in the field of structural reinforcement. Reconstruction work on the vaulted ceilings started in the spring of 2022 after the teams of builders and stonemasons had been trained by Mapei on how to use the solution correctly. The work was carried out every day with the utmost respect for the structure and with the competence of various experts in the restoration of historic monuments.

The product employed was a pre-blended, natural hydraulic lime (NHL) and Eco-Pozzolan mortar, which was reinforced with a glass fibre mesh, a solution specifically developed for consolidating historic structures and approved by the team of three architects specialised in historic monuments who are leading the project: Philippe Villeneuve, Rémi Fromont and Pascal Prunet, with advice on structural strengthening provided by the Italian architect Carlo Blasi. The solution proposed by Mapei underwent a whole year of testing, with numerous experiments conducted in the lab and on site, before being finally approved by the three architects.

“This structural work, which acts as a kind of shell, gives back the masonry vaulted ceilings their original resistance and shape - says Thomas Briac, the engineer in charge of the works for Lefèvre -, alleviating the effects of any future movements and preventing fractures in the joints with the adjacent structures. Being able to rely on the most cutting-edge technology is of enormous help because working on something that is part of our heritage does not necessarily mean it is not of our time”.

“Mapei’s extensive experience of using mortars for consolidation and restoration work was greatly appreciated - says Carlo Blasi, Works Management Consultant for the restoration work -. Mapei was able to demonstrate that its materials had been tested, had undergone various tests and that they had been awarded certification for their mechanical properties and characteristics”.