The Notre-Dame-d'Auffay collegiate church enters the last phase of its renovation with the restoration of its spire to a height of 72 meters

After six years of work, the Notre-Dame-d'Auffay collegiate church (76) has entered its sixth and final phase of renovation with the removal and restoration of the spire. A crucial step which requires the installation of a self-stable scaffolding 25 meters high, for which Tubesca-Comabi is responsible for supplying, assembling and dismantling.

Located in Val-de-Scie, in Seine-Maritime (76), the collegiate church of Notre-Dame-d'Auffay is a monument dating from the XNUMXth^ecentury. Large-scale restorations began in 2017 on this building, classified as a Historic Monument. A careful organization in six key stages, with a firm phase and five conditional phases, enabled the rehabilitation of the collegiate church. This year, the rehabilitation project entered its final phase, considered crucial in the preservation of this heritage monument.

Technical challenges overcome by a tailor-made solution

French leader in the manufacturing and marketing of access and work at height solutions, Tubesca-Comabi is responsible for the supply, assembly and dismantling of scaffolding, throughout the construction site. This last stage, which consists of the complete renovation of the top of the spire, required the installation of 36 levels of scaffolding over a height of 72 meters. For Tubesca-Comabi, the most complex technical challenge, at the level of the boom, was the installation of a self-stable scaffolding at a height of 25 meters, to allow craftsmen to intervene in complete safety and efficiency .

With this large-scale renovation project comes a whole series of technical and logistical constraints. In order to ensure the restoration of the spire, specific equipment had to be put in place to ensure the safety of workers at a height of 72 meters.

The structure was imagined and designed to facilitate access to the various trades and consists of:

• An M368 multidirectional exterior scaffolding one meter wide
• A self-stable scaffolding, at the level of the spire, to a height of 25 meters
• Two interior scaffoldings : in the bell room and at the level of the spire, to reinforce the exterior scaffolding and simplify the work of the stonemasons
• Protective nets around the bell tower with supply systems at 53 meters
• A 70 meter UNISTEP staircase to simplify access for renovation teams.

Likewise, the feet of the other scaffolding resting on the heights of the collegiate church, additional precautions had to be imagined and established to avoid their damage during the duration of the work.

The construction site in figures:

• 6 years of work and 6 stages
• 85 tonnes of materials used
• 36 levels of scaffolding 72 meters high
• A self-stable scaffolding 25 meters high

A word from Jean-Charles Durand, works engineer at Tubesca-Comabi

Beyond the prior technical constraints, were you faced with other constraints on the site?

We had to face several technical difficulties, in particular to reduce the forces on the roof supports. The steep slope therefore led us to reduce the mesh at the base of the scaffolding to facilitate the work of the erectors and reduce the load on the feet. Underpinnings were also added under the roof to relieve the frame. The other main difficulty was to make the scaffolding self-stable over the last 20 meters, the arrow being removed in order to be rebuilt. Support was impossible on this one.

Is there a point you would like to emphasize?

On this type of site, it is very difficult to fully understand the duration of the assembly time. Many hazards are taken into account, notably the delivery of parts; these are repeated up to four times before being put in place. This will lead us to think differently during our future major projects.

How would you describe this project?

This project proved to be very enriching both technically and organizationally and will allow me to approach our next projects differently. On a more personal note, I consider it a real privilege to be able to explore the interior and top of a spire! An impossible visit without scaffolding, not to mention the surrounding view from the summit.