In pursuit of tomorrow | Gironde. Bordeaux at the top of wooden construction

Table of Contents

• 1 Wood stores carbon
• 2 Better thermal quality
• 3 **What specific technological advancements are enabling architects like Mr. Viguier to design ⁣and ‍build ⁤taller and⁤ more⁤ complex wooden structures?**

It doesn’t look like a cabin in Canada, or as straight as a skyscraper in New York. And yet, the Hyperion tower, built by Eiffage, in Bordeaux, near Saint-Jean station, is actually made of wood. It is also a result of technical ability. With its 55 meters high, its 16 floors, its 98 housing units and the 1,400 cubic meters of wood hidden in its structure, it is the tallest wooden building in France… Because in a year, on the other side of the street , in this same area, Armagnac, designed by the public development center (EPA) Euratlantique Bordeaux, another wooden residential tower should rise just a few meters more: Silva, “forest” in Latin and the work of developer Kaufman & Broad.

This race to the top and innovation appeals to the EPA Euratlantique Bordeaux which is committed to ensuring that all new projects on the sites it surrenders on the banks of the Garonne are carried out with great some wooden structures. The reason? The use, in the construction of this renewable resource, significantly reduces the carbon footprint of buildings throughout their life: from the growth of the tree to the demolition of the structure. For the Hyperion tower, 45% less carbon is released into the atmosphere compared to a conventional construction of the same scale.

Wood stores carbon

To understand why wood is truly more ecological, we must first look at what happens at the beginning of any real estate project: the production of materials. Although the manufacture of concrete is energy intensive and polluting, as it requires sand, water and cement (itself made from limestone, clay and sand heated to 1,500°C), forestry – l is not a rational use of forest trees – producing carbon. Even better, she has some. “Trees are made up of CO2 which they consume to grow. So by using them for construction it will be possible to capture and preserve carbon​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​in buildings,” explained Hugues Petit-Etienne, orderer at Fibois Nouvelle-Aquitaine, an interprofessional association in the forestry industry and paper.For the Hyperion, this is roughly equivalent to 1,000 tonnes of this greenhouse gas fixed in the beams, floors and other structural elements.

Another benefit that is good for the environment at this stage: allowing the trees to grow to a great height sustains the ecosystems. “Big trees themselves support biodiversity: in the bark for lichens or in the hollow of the roots for small animals. The soils are also less stressed when tree planting is done over a longer rotation. It is good for filtering water, air, all the services that forests offer us that are not damaged,” explained Christophe Chauvin, forest network manager at France Nature Environnement. So there is no felling of trees large, without clear or heavy demolition, harming nature.

Better thermal quality

Once the wood is produced, it is modeled in the workshop, it is a dry site. “Everything is done in the factory in a very clean and precise way with machines connected to the digital model of the project. The panels are assembled on site as a construction set. No noise, no dust. Which makes wood a very welcome material in city centers because you don’t create distractions around you,” said Jean-Paul Viguier, architect of the Hyperion tower.

Three to five times lighter than a traditional structure, a wooden building rests on smaller foundations. For Hyperion, the use of concrete was limited to the foundation, the first three floors and the central ridge that houses the stairs and elevator shafts. Also, throughout the life of the building, the thermal properties of the wood, winter and summer, are much better. Finally, if it is dismantled, the structure can be recycled into energy wood, as long as they do not contain toxic glues. “Work is underway on biosourced glues, but they are expensive,” said Hugues Petit-Etienne.

Conclusion, the benefits of comfort and durability of wooden construction compensate for its cost, which is still higher. It is also an ecological solution as long as you have material from well-managed local forestry. This is good, with its 2.8 million hectares of forests, New Aquitaine is the largest forest area in mainland France.