With almost all Vendée Globe-skippers safely returned to les Sables, the craze around this sailing event draws to an end. At least the „active“ craze. Now it is time for many retrospectives, for the skippers, teams and professionals to draw their conclusions and learnings. After the race is before the race: Vendée Globe 2028 is already casting ist shadows. With the cards being re-shuffled, old and new contenders for the crown of professional singlehanded racing are setting up their tools to start yet another race around the world.
One of them is skipper Marc Thiercelin, a well-known and very skilled pro-sailor who has an impressive Palmarés in terms of sailing: Five times Vendée Globe participant, with two times being second. Seven Solitaire du Figaro participations and all in all 22 (!) transatlantic races done, he is one of the „old salts“ and definitely a legend in French sailing with over 700.000 nautical miles of offshore ocean racing experience. He missed this edition of the Vendée Globe, but he will participate in the upcoming of 2028. By the way, his old IMOCA has been used to shoot the movie „Turning Tide“. Now, why should that all be newsworthy? Well, because he will do this Vendée Globe 2028 in an IMOCA made of … wood!
Talking to Gildas Plessis, designer of the wooden IMOCA of Marc Thiercelin
Sustainability, reduction of environmental impact of sailing and many more topics are more than „en vogue“. Apart from the usual greenwashing PR-stunts, many people, brands and companies are investing a lot to make sailing more sustainable. The comeback of timber in modern boatbuilding is a huge thing. A topic, I have already covered in many articles, be it about La Rochelle-based RM Yachts, some adventurous private projects or lately the wonderful Woy of German boatbuilder Jan Bruegge. So for now I start my series on this great project by talking with yacht designer Gildas Plessis. He and his team of dedicated professionals are making Marc´s dream of a powerful IMOCA come true.
Lars Reisberg | NO FRILLS SAILING: „Gildas, what a great project! Let´s start by telling us more about your company. You and your team are based in Lorient, right? Is it because „La Base“ is the epicenter of performance sailing in the world?“
Gildas Plessis: „Well, yes…and no. Let me explain: In April, the company will celebrate 30 years in designing boats. Originally we were based in Nantes – a major Breton trading port, hometown of Jules Vernes, but still quite far from the ocean. Wanting to get closer to the heart of maritime and oceanic Brittany, we relocated only 18 months ago just a stone’s throw from „La Base“ in Lorient. We are now immersed in a dense ecosystem favorable to our projects. Close to shipyards, manufacturers, customers and key partners for CFD and structural analysis, like Bañuls Design or GSEA.“
Lars Reisberg | NO FRILLS SAILING: „Marc Thiercelin announced he´d participate in Vendée Globe 2028 in an IMOCA built from wood – you are named the naval architect/designer of that boat. How did you come to be involved in Marc´s campaign?“
Gildas Plessis: „It went that way: We proposed a study to Voiles Magazine, a major French-speaking sailing publication, on an IMOCA capable of meeting CO2 limits in line with the Paris Agreement and the “Offshore Racing Conferences” organized by the French Sailing Federation. You see, our passion has always been high-performance sailing, from lake regatta boats in Switzerland and Canada to one-off IRC 3 or 4 designs, units at the origin of Class 40 and Mini 6.50 plywood prototypes. The IMOCA class, combined with a sustainable approach, naturally inspired us, aligning with the philosophy behind the hundreds of boats designed by our agency.
In February last year this the 8-page article was published, adopting a scientific approach: It was objective and methodical without any „militancy“, as I´d call it. It presented a clear demonstration of the methodology, the materials considered, and the results. Following this publication, three offshore racers reached out to us. Eager to develop their future IMOCA boats with my team and our partners. Marc himself is an exciting and remarkable sailor! He comes up with an incredible track record as you know.
The third team, Mer Connexion from Marseille, comes from the Class40 and Class 6.50-circuits. Now, the „Greenscow-project“ was born with the support of two major players in offshore racing: My colleague and friend Renaud Banuls, renowned for his work on CFD including (but not limited to) as the architect of the Sodebo ULTIM trimaran and the structural engineering agency GSEA. They are responsible, for example, for the calculations behind the top IMOCAs of the Vendée Globe, like Paprec-Arkea. Now, with this team in place, we are able to tackle the following challenge: How can we integrate more natural fibers into offshore racing sailboats without compromising performance?“
Lars Reisberg | NO FRILLS SAILING: „On your website there are some 3D-renderings showing the „Greenscow“ IMOCA: Will that be Marc´s boat?“
Gildas Plessis: „Yes, this is version 1 of the project, ideally with daggerboards rather than foils to reduce CO2 emissions and environmental impact as much as possible. As Jean Le Cam explains very well, daggerboards are simpler, require less structural reinforcement, and ultimately have a lower environmental impact than foils have. Marc seems quite receptive to this approach at the moment.
Since then, we have been exploring, alongside the two other skippers, about a version with foils, obviously more powerful than the daggerboards version, even if we are not aiming for the podium. Because our goal is to tell the story of sustainable performance. There is a fascinating issue when it comes to achieving an imposed ecological transition of minus 30% in 2030: Reducing the global impact without “shattering” performance.
You see, offshore racing is, at its core, a game. Nothing more. A race like the Vendée Globe is akin to a high mountain race. It serves no real practical purpose in a Cartesian sense, yet it remains a beautiful and extraordinary human adventure. So if this adventure can achieve a 30% or even a 50% reduction in CO2 emissions at the only cost of being even so slightly slower … well, then the question is really worth asking, right? And our skippers are seriously considering this approach. Hull design will vary based on these choices: Either a wider one for a “dinghy-style” setup or a narrower one for a foiler. Recyclability is also in play or we could potentially source second-hand foils, whether from existing designs or spares already produced. A lot is still open.“
Lars Reisberg | NO FRILLS SAILING: „Why was wood chosen in the first place to be the material of choice for this boat? I mean, isn´t carbon fiber the one and only superior material for making a boat that has to withstand the stresses and challenges of the Horn or the constant storms in the Roaring Fourties?“
Gildas Plessis: „We have very strong experience in modern wood at our agency. Of the total of 360 sailboats and motorboats we’ve designed, nearly 70% of units were built using epoxy-plywood, strip planking or cold molded wood. Among these units, motor boats the Volterra 25 or the Furtif 28 in Switzerland, are both designed to plane and withstand hull impact at 30 or 35 knots.
Our first Class Mini 650s in plywood, a proto with a centerboard, has been surfing at 25 knots under a large spinnaker for 20 years. The same goes for large charter catamarans such as Etoile Magique. This one is 24 metres long and displaces 40 tons. It is built with Okoumé plywood and carbon fibers which has had more than 30 Atlantic crossings without any damage.
You see, wood offers a significant structural advantage: Unlike a neutral-core material, its young modulus is very different and its fibers actively contribute to load distribution. This allows for high mechanical efficiency while maintaining a reasonable mass. Our very extensive experience with wood materials allows us to answer the following question: How to withstand the extreme loads of an IMOCA which surfs or flies at 30 knots? Well, by combining the two materials: More carbon in all highly constrained areas, less carbon and more plywood wherever the first can be reduced. As a result, the slamming impact targets of the latest foilers, which is several tens of tons per square metre, are are fully accounted for in our approach with this technology. And critically, the work of GSEA for the finite element calculation of the forces of the “ship beam” and the very localized forces is fundamental to ensure structural integrity. You see, wood is absolutely capable and a very, very modern material indeed.“
Lars Reisberg | NO FRILLS SAILING: „When designing a wooden raceboat, what is different in your work to designing a yacht from, let´s say, standard composite materials?“
Gildas Plessis: „The method remains strictly the same. The input data like shear, traction and compression are depending on the materials used. A modern wooden racing sailboat is, fundamentally, a composite sailboat indeed! There are of course plywood panels and glass, carbon, linen, basalt or bamboo fiber fabrics. To refine our data and consolidate our models, we work with universities for doctoral and master’s theses on hundreds of samples to further refine the data and cross-reference our ISO or inhouse computational models, to get as close as possible to mechanical reality.
Keep in mind that we have over 70 years of hindsight with all modern wood techniques. This is not a major innovation – but rather a retro-innovation! We pick up the story where it left off. Exactly like scows, totally forgotten in Europe and which today form the majority of racing sailboat hulls. A man named Duggan invented them in Canada in the 1890´s …“
Lars Reisberg | NO FRILLS SAILING: „Can you specify which parts of the IMOCA will be built the same way like any other and which parts will be different? Like for example, the structure, stringers, bulkheads et cetera …“
Gildas Plessis: „Certain extremely constrained areas such as the keel head, the mast foot bulkhead and specific pieces will remain 100% carbon. I emphasize the following point: Reducing the amount of carbon does not mean we can eliminate it. It’s a fabulous material. Which I also find very beautiful, quite martial, light and so effective. Just think of an IMOCA-hull in monolith carbon: It only has a thickness of a few millimeters! Fascinating! On the other hand, the idea of emitting almost 550 tonnes of CO2 for an object that weighs less than 9 tons does not appeal to us so much. For the moment on the “daggerboard” version our target is 200 to 240 tons of CO2 for a weight which would be 400 to 600 kilos higher than the latest IMOCAs. So, we need carbon. But in the right places, draped in the most optimal way to create an intelligent association between natural fibers and carbon.“
Lars Reisberg | NO FRILLS SAILING: „Which timber will be used for Marc´s IMOCA? Is it comparable to the good old square rigged sailing ships, where only the finest hard Oak has been used for the frames, Pine for the planks and Teak for the deck? Where is the timber for Marc´s IMOCA sourced from?“
Gildas Plessis: „Oh, that is a great question indeed! We have been working on this specific subject for many years, opting for the most ethical and responsible posture possible. Should we choose Finnish birch plywood, which we recently did on a motor catamaran. Or go for European, certified but heavy density or work with African plywood like Okoumé which is lighter but with the risk of deforestation?
Well for years we ruled out Okoumé for obvious reasons. Then we found two panel manufacturers who guarantee the highest level of commitment with three serious European labels regarding exploitation. Two examples: The 1 hectare-plots managed by these manufacturers guarantee that only one tree is taken per hectare, then the plot remains unexploited for another 25 years. One more example: Sliced wood like the Okoumé leaf which is used to make the panels, is produced in Gabon to allow the local economy to benefit directly from the wood trade. This is a major issue in our approach: Yes!, to replacing carbon with plant material … but only if this does not harm the forest!“
Lars Reisberg | NO FRILLS SAILING: „Are there any other specialties in Marc´s IMOCA, like electric energy production, propulsion etc. which make it stand apart from the other boats?“
Gildas Plessis: „Oh yes, the are! We mainly work on sailing performance by playing on our material and CO2 emitted cursors. We do this for example with the All Purpose sailmaker which includes 50% linen fibers in its mainsails. The IMOCA APICIL has just completed a Vendée Globe with sails of this type. Other areas of research applied to foils and fins with Heol Composites and Avel Robotics are extremely interesting. I’m thinking of the recyclable foils that Avel Robotic is testing on its Minilab project. There are many exciting subjects to work on to slowly change the hyper-carbon model towards a sustainable model.“
Lars Reisberg | NO FRILLS SAILING: „Where will the boat be built and what is the general timeframe? When will she see the water for the first time?“
Gildas Plessis: „Three shipyards responded to our call construction. Upstream, we have a “wood” phase with all the engineering from the agency and the plywood cutter. That´s a company that has been with us for 25 years, managed by Kaori Concept, a wooden boats specialized shipyard. Its role in the summer of 2025 will be to create the plywood kit. Then the shipyards selected to “carbonize” and assemble the kit will be able to work on the fiber assembly of the boat. The first desired race for Marc´s IMOCA will be the Route du Rhum in November 2026. The goal is to be absolutely ready for the 2028 Vendée Globe, of course.“
Lars Reisberg | NO FRILLS SAILING: „Have your something you want to tell the readers which I haven´t been asking in this interview?“
Gildas Plessis: „On these topics, which are fundamental for the future of our societies and efforts for containing global warming, there is a key point that must be addressed calmly. We do not express opinions, we do not have an activist posture. But rather a rigorous and open-minded approach. Designing a racing or performance cruising yacht without a mold is not a revolution. Building with natural fibers is nothing new — humans have done it for centuries! The real challenge, and the real excitement, lies in optimizing and opening possibilities. We are architects. We sail. We are part of a long and evolving tradition of yachting. This evolution requires a conscious, scientific, and creative approach. It’s in our DNA. And we share this vision with many companies thriving toward the same goals.“
Thanks so much, Gildas, for this first insigt into your amazing work! I hope I can come and visit the building process of the wooden IMOCA maybe end of ´25? For now, all the best to you and your team!
Pictures © Copyright with kind permission by Gildas Plessis / Greenscow & Marc Thiercelin
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