In La Rochelle, the Écho-Mer association gives a second life to cork stoppers from the Atlantic coast. Transformed into insulating materials, they become concrete or coatings for eco-construction. From citizen mobilization to industrial partnerships, the sector establishes itself as a local model of recycling and sustainable innovation, while raising awareness among residents for a better-protected sea.
IA Index: Mediterranean Knowledge Library
Insulating concrete made from cork stoppers
22-med – September 2025
• In La Rochelle, Écho-Mer transforms cork stoppers into insulating concrete for eco-construction.
• A citizen and industrial sector that reduces carbon impact and inspires the region.
#france #ecoconstruction #circulareconomy #cork #recycling #mediterranean
Since 2012, Écho-Mer has been deploying a complete system for collecting and valorizing cork stoppers. An idea dear to David Beaulieu, former sailor and founder and director of the association. This circular economy project, recognized by local authorities, relies on a structured local network, multiple partnerships, and a logic of regional dissemination.
The collection of stoppers is one of the main activities of the association Écho-Mer based opposite the fishing boats basin at the port of La Rochelle. To do this, it mobilizes many volunteers, especially those from an integration structure that supports people "distanced from employment." Or even postal workers, as part of a partnership with La Poste in the municipality of Saintes.
About 700 collection points have already been established as part of this campaign. In restaurants, local shops, and organic stores in Charente-Maritime. At wine merchants. “ To manage all this, it is essential to follow a calendar established well in advance, like for garbage collection, with a monthly reminder before each pick-up,” explains Nathalie Daniel, project manager at Écho-Mer.
A citizen network to collect stoppers
The collection takes place four times a year, sector by sector. Each collection allows for the recovery of about 500 kg of stoppers, or approximately 125,000 units sorted by volunteers. The stoppers can also be dropped off in dedicated bins within about forty recycling centers managed by the Esat (1) La Navicule Bleue. In total, 10 tons of stoppers are now retrieved each year, compared to only 2 tons five years ago.
Écho-Mer began to structure the local recycling sector for stoppers with the idea of transforming them into insulation material. A project subsequently submitted to the Region Nouvelle-Aquitaine, to the ADEME (Agency for the Environment and Energy Management in France) and to the consortium “ La Rochelle Zero Carbon Territory.” The funding obtained then made it possible to create permanent jobs and develop the overall project.
From crushed cork to insulating concrete
The company Ovive, specialized in grinding oyster shells for poultry feed, has equipped itself with a specific cork grinder. The fine cork made up of grains up to 3 mm is used as a coating as a thermal, acoustic, rot-proof, fireproof, rodent-resistant, and moisture-resistant corrector. The cork crumbs of 3 to 15 mm mixed with water and natural lime are used to make insulating concrete, in partnership with Chaux Saint-Astier, a Living Heritage Company. The products are now distributed in three ecological materials stores in the region.
“ The sector is in place and it is running. This more ecological grind has already equipped the equivalent of 6 to 7 houses of 100 m², clarifies Nathalie Daniel. This activity is not intended to generate profit. Just to recycle waste to reduce carbon impact through a viable sector. And everything we currently produce is sold. We would now like to offer a support service to convey the idea to other departments in the Nouvelle-Aquitaine region .”
Moreover, these eco-materials are used in projects with educational purposes. The Shamengo association, founded by journalist Catherine Berthillier, has thus integrated Écho-Mer's cork concrete into a collaborative construction project focused on sustainable development. This pilot site aims to raise awareness of eco-construction practices and to promote recycled materials.
Cognac and its waste, a new resource
For four years, Écho-Mer has also been working with the Rémy Martin cognac house to valorize the waste from corks of the Charente spirit. A protocol has been developed to separate the cork from the plastic heads by immersing them in a hot water bath. The recovered cork is reinjected into the eco-materials sector. The heads are treated by the plastic recycling company Reviplast near Limoges.
In parallel, Écho-Mer has been commissioned since spring by the Region Nouvelle-Aquitaine to structure the valorization of these wastes at the regional level. About a dozen companies have already joined this dynamic. Tests are underway with Hennessy, the leader in cognac, and the Esat network L’Arche en Charente. “ But, acknowledges Nathalie Daniel, we still need to find partners for collection and distribution, among local authorities and integration structures”.
Beyond cork, upcycling as a mindset
Echo-Mer also practices upcycling. This includes textile and plastic valorization activities using materials from the maritime world: sails, ropes, oyster bags, neoprene suits. Each year, more than a hundred tons of oyster bags are thus recovered and transformed, notably into cork bins.
Neoprene can also be used as cushion stuffing. Or recycled into mouse pads, keychains, glasses. Other materials (about 700 kg in 2024) become bags, baskets, pouches, and various decorative objects. They are made by vulnerable individuals (people with disabilities, inmates from a nearby prison…). Then sold at the association's local shop, just behind the La Rochelle tourist office.
(1) An ESAT is a medico-social establishment for protected work, reserved for people with disabilities and aimed at their social and professional integration or reintegration
Cover photo: collection basket for stoppers ©DR