Technical control of an adobe building in the heart of the Confluence district in Lyon
The Ydeal project was developed in a logic of sustainable real estate. Within this set of 5 buildings, the Orangery innovates by bringing up to date the traditional technique, which presents in particular remarkable thermal performances
- Project name: Ydeal Confluence
- Date: Delivery in December 2020
- Client: Ogic
- Size: 12,500 m² of floor space
- Location: Lyon, Rhône.
Talk to our experts
In the heart of the Confluence eco-district at the tip of the Lyon peninsula, the Ydeal building complex has been developed around three concepts: reversibility, conviviality and eco-responsibility. The developer of the project, Ogic, is composed of five buildings, with a total surface of 12 500 m² of floor.
The smallest of the five buildings, the Orangery, stands out from the others due to its small size (750 m² on three levels), but above all by the materials used for its construction. Ogic wanted to experiment with a technique that was once widespread in the region: adobe. This is clay soil, which is compacted without any additives, then dried. Once dry, it does not rewet in depth and presents excellent performances in terms of insulation. The rest of the structure/fitting out were entirely made of wood, with a construction that is 100% in bio-sourced materials. The terrace is planted with vegetation.
The other four buildings are apparently of a traditional design, using concrete as the main material. Their eco-responsibility lies in their sustainable design. They are designed to be easily adapted to new uses, which is known as the principle of reversibility. The load-bearing elements have been reduced to a minimum, so that the floors can be easily transformed into housing or offices, depending on future uses.
The four main buildings are also covered with photovoltaic panels, with a collective self-consumption system. This is a first in France given that is such a large building complex, with the ambition to meet 50% of the occupants' energy needs when it comes to solar energy.
The project has been awarded the HQE, BREEAM and Effinergie labels.
DESCRIPTION OF THE MISSIONS
Our Construction and Real Estate team in Lyon carried out the technical control of the whole project.
The use of the rammed earth required additional attention:
- The most compressed blocks at the base were manufactured more than one year before their installation, so they are quite dry. The following blocks were produced directly on the site as they were built.
- Since the delivery of the building, our teams have been monitoring the behaviour of the material and the structure over time, as well as the evolution of the humidity level in the heart of the adobe.
"To complete the experimental process, the choice was made to build load-bearing adobe walls. The design of the building was conceived as a nod to the arches of the orangery in the famous Parc de la tête d'or, on the other side of the Rhône. We thus had to find solutions to push further the usual framework of use of the raw earth ".