The restoration of the façades, 2008-2009.
The Hôtel de Sully, headquarters of the Centre des monuments nationaux, is one of the most beautiful private mansions in the Marais district in Paris. To improve its presentation to the public, in 2008 and 2009 it underwent an extensive restoration campaign.
The restoration campaign, both external and internal, was conducted on behalf of the CMN under the project ownership of the Service national des travaux, with chief architect of Historic Monuments, Jean- François Lagneau as the main contractor.
The façades on the main courtyard and the Rue Saint-Antoine of the Hôtel de Sully, restored in the 1950s and 60s by cement screed works, were crumbling. They were also dirty because of pollution. The degraded façades and sculpted elements therefore required major restoration work, mainly cleaning and being made safe.
The crumbling facings - Restoration of cornices, with the replacement of some stone blocks / Photo: CMN
What were the challenges and constraints at this site?
This work, essential for the presentation of the building and people's safety, took place in a restricted space on an occupied site, i.e. in the presence of the personnel and the public. The latter had to endure the inconvenience related to noise and dust for a year as well as the constant obstruction of scaffolding, etc.; we had to explain why such constraints were inevitable. Tours of the building work helped people to understand better.
Dirty sculpted frieze, eroded decoration of the Hôtel de Sully / Photo: CMN
What did the architectural work involve?
As is often the case on a historic monument, the work was intended primarily for good transmission to future generations, so it was necessary to repair the damage that was found due to passing time and the use of unsuitable materials, while preserving the authenticity of the façades. What now appears as simple cleaning was in fact much more complex.
Restoration of the coffered vault ceiling of the entrance hall / Photo: CMN
The work, conducted in partnership with the Kärcher company, included cleaning the facings and sculpted elements, replacing certain stones and applying preventive treatment for all the façades.
Cornices, string courses and sculpted bas-reliefs that showed signs of erosion were consolidated. Lastly, a harmonisation patina was applied for overall homogenisation.
To guarantee the success of this project, the chief architect of historic monuments called upon the skills of many service providers, bringing together stonemasons, stonecutters, sculptors and lab engineers.
The restored façades of the Hôtel de Sully / Photos: Philippe Berthé / CMN