Lemoal Lemoal architecture and landscaping office has delivered the first new public building constructed with hempcrete blocks in France, the Pierre Chevet sports hall for the town of Croissy-Beaubourg (77).
The fruitful collaboration between manufacturer, architects and construction companies was the opportunity to experiment with an innovative and sustainable implementation.
Mixed hemp and wood structure
The project's structural principle was lead by the determination to employ long-lasting materials with multiple performances. The wooden half-vaulted porticoes, which free a maximum of space for practicing sports, lean against a wall of hempcrete blocks for support. These hempcrete blocks have been chosen for their many comfort- and safety-enhancing - qualities, among which their high thermal, acoustical and structural performances and fire-resistance (REI 30).
Hemp, a short supply chain
Made by the cement manufacturer Vicat, the hempcrete blocks chosen here are manufactured with hemp hurds, an agricultural material obtained from hemp, which until now has been without a market. The fibers are from plants cultivated in France and then assembled at less than 500 km from the project site. Durable, high-performance and innovative, hempcrete and its use in building blocks boosts the commercial value of short supply chains, mobilizing actors in France, from the farmer to the worker.
Mostly employed in detached houses, hemp is generally treated with a finishing coat of plaster on the exterior. Here, to facilitate their upkeep, the façades are covered in cladding whose panels can be individually replaced. Lower sections of interior surfaces have been treated with hemp plaster. On the upper parts, the hempcrete blocks have been left exposed, thereby maintaining their acoustical qualities.