In Carquefou, a condominium protects itself from the weather thanks to Sto solutions

Rains and westerly winds: for the inhabitants of the Nautilus residence in Carquefou (44), protection against bad weather is a priority.

For Laurent Bobin, President of the Syndicate Council: “Fifteen years after the construction of the building, we have identified weaknesses in the waterproofing, which required a complete renovation of the facade. »

Protect facades but also balconies

The 35 co-owners therefore wished to give a new youth to the two buildings of the residence. The diagnosis and the studies were entrusted to the company Batimex, project manager specializing in the exterior envelope of the building, which then acted as project manager.

For Batimex manager Nicolas Rivoal: “The risks of infiltration were concentrated on the connection between the floors of the balconies and the walls: the drainage sheet installed under the tiles no longer provided optimal protection. We therefore recommended a continuous waterproofing solution between the facade and the balconies, protecting the entire building against the passage of water. »

Continuous implementation

Selected with Soprema Entreprises for the construction site, the Sto teams proposed a class I3 impermeability system, which provides superior resistance to cracking without the need for reinforcement. In the end, the solution integrates several Sto products on the facade: the StoPrim BL base regulator, the Irtop SC intermediate layer, and the Irtop S K1,5 floated waterproof coating. Initially, teams from Soprema Entreprises repaired the facade, covering the cracks. On the balconies, they also broke the tiles, the drainage sheet and the original screeds.

A fiberglass profile for balcony nosings

The waterproofing of the building then started on the balconies, with the creation of new micro-screeds, then the application of a liquid waterproofing resin covered with a tiling finish. The balcony nosings were protected with the StoDeco Line KB profile in fiberglass, in order to prevent the appearance of greening. To ensure perfect continuity between balconies and facades, Batimex asked that the waterproofing resin be implemented as a barrier against rising damp on the first 20 centimeters of the walls. The works company then applied the Sto waterproofing complex to the facades. Finally, to ensure the continuity of the film, the Soprema Entreprises teams made the joints with the Irtop S Velouté Mat coating.

Strong aesthetic expectations

Another strong point of the site concerned the realization of the finishing coating. Built in 2004, the Nautilus residence incorporates several of the codes of regional architecture: slate roofs, basements clad in stone, and exterior walls of dressed stone appearance. An aesthetic quality that the co-owners wanted to keep when starting the renovation work. "The complexity was to reproduce with the I3 impermeability system the imitation stone desired by the client", notes Hubert Minaud, Sto project manager. The Sto teams were also asked for advice on harmonizing the colors of the building, via the StoDesign service: their intervention made it possible to use the two original colors of the building on the new facade (creamy white and yellow), maintained there again at the request of the condominium.

A meticulously crafted stone look

When applying the waterproofing coating, the challenge was therefore to reproduce the cut stone appearance, originally produced by scraping the coating. For this, the works company had to apply masking strips approximately 1 cm wide, corresponding to the thickness of the false masonry joints. “The tape had to be removed quickly, before the coating was too dry, to avoid any risk of tearing off the edges,” explains Franck Le Ster, works supervisor at the Soprema Entreprises agency in Carquefou. To master this timing, it was necessary to adapt the organization of the site by working on reduced surfaces. In total, the works company mobilized a team of three to four workers for this renovation for a little over eight months.

“A result at the height”

“The result is up to the objectives in terms of budget and aesthetics, welcomes Laurent Bobin for the co-ownership union council. We are very happy with the work, with the aim of protecting the building for at least another fifteen years. »