MATERIALS

CONCRETE AND TIMBER: LOW-CARBON OBJECTIVE

Limiting the carbon footprint of buildings requires rigorous selection of the materials used to make them. These materials must use local resources, be recycled and comply with a dynamic of low-carbon construction.

RECYCLED CONCRETE IS BETTER FOR THE ENVIRONMENT

Plastic, glass, paper and aluminium are all now commonly recycled. But what about concrete? In line with its sustainable development objectives, Lyon Confluence has decided to take up the challenge with the support of its partner Vicat. The objective: reuse construction waste to produce, for the first time in France, 100% recycled paving concrete.

 

This sustainable material, which already covers the entrance to the Station Mue park and the H7 forecourt, is manufactured from surplus concrete and will soon cover all the public paths in Le Champ. This “returned mixer concrete” is crushed to obtain aggregate, which is the base for recycled concrete. The end product boasts a refined, classic aesthetic and an equivalent life span to that of standard concrete: at least 20 years. It also allows a considerable reduction in the amount of resources used, which could also be a source of inspiration for the construction industry of tomorrow. In France, some 260 million tonnes of construction waste are produced each year.

TIMBER, A RESOURCE WITH GREAT POTENTIAL

A renewable resource, timber also offers excellent thermal and sound insulation. This "carbon trap" material allows walls to breath and has proven to be as light as it is strong. It was quickly incorporated in the development projects of Lyon Confluence, which encourages its use on condition that it is certified FSC (Forest Stewardship Council), guaranteeing sustainable forest management.

In La Confluence, timber frame construction has been chosen for several buildings in the district, thus reducing the use of concrete in the foundations.

MJC PRESQU’ÎLE-CONFLUENCE, THE POWER OF TIMBER

This building designed by Marcillon-Thuillier Architectes won the Rhône-Alpes timber construction award in 2014 (87 candidates). The award, organised by FIBRA (Rhône-Alpes Wood and Forest Federation) aims to promote and reward teams composed of an architect, timber design office, timber company and a contracting authority for structural and building designs that include a significant amount of timber. Architectural quality, technical performance of the timber, environmental approach and energy performance are just some of the criteria upon which the judges base their decision.

Albizzia, the first timber-frame block

A project of 14,000 m², the C2 Sud block, will be the first construction in La Confluence to have three of its five buildings made using timber frame, one of which is an impressive structure of 16 storeys. The use of this local and bio-sourced material for such a project will considerably reduce the quarter’s carbon footprint and lessen site disturbance for the local inhabitants. This innovative design was the brainchild of the developers UTEI-WOODEUM in association with the designers Hardel Le Bihan and Insolites Architectures.

Albizzia by UTEI-Woodeum