Yannick Cougnaud “We can’t build like we used to”

Carbon-free construction is no longer a myth; it’s been made into a reality by a developer that has been committed to ecology for many years.

As part of our second magazine ForHum, we met with Yannick Cougnaud, Director of Ouest Réalisations and founder of the Green Label Alliance. One year after its creation, he looks back on the challenges of low-carbon construction and the projects under way and to come. 

ForHum: One year after its creation, what is your initial assessment of the Green Label Alliance? 

Yannick Cougnaud: Current events show us the urgent situation we find ourselves in. We can’t build like we used to. A year ago, the primary objective was to raise awareness of low-carbon solutions among all those involved in the construction industry, upstream of calls for tenders and projects. Today we’re launching our first low-carbon programmes, reaching C2 level, as well as advancing our work on the first low-carbon district in Europe in Nantes. In partnership with project management teams, design offices, inspection bodies and ecologically responsible companies, the Green Label Alliance demonstrates our willingness to build carbon-free, by a specific reference system co-developed with Socotec and a Charter of Commitments. Today, six companies have signed this Charter, Hoffmann Green of course, but also Unikalo, the manufacturer of a range of 95% bio-based paints.  

So can we say that today, building carbon-free is a reality and not just a dream? 

Absolutely! Carbon-free construction must be considered as a whole, with analysis of the carbon footprint of the actors, materials and technologies available. We’re involved from exploring the ground treatment, to the peripheral analysis of the project, through to the construction of the building itself… We consider the programme’s complete life cycle. 

Upstream, this involves, for example, simplification and eliminating some business travel by developing video-conferencing. It involves analysing design – we think about the quantities to be used to best protect the resources… All aspects of project implementation are reviewed and verified. This includes the choice of routing and worksite machinery. We favour local companies… We also ensure the treatment of everything that is removed from the worksite… This means that the Green Label Alliance is not just materials, but a determination to involve the entire chain of actors. 

Our first Green Label Alliance programmes are now under way: the Hauts de Tanchet in Les Sables d’Olonne and the assisted living facility built for the national company, Senioriales, on one of our lots in Les Sables d’Olonne. The first stone will be laid in May 2020. 

Does low-carbon constructionhave an effect on costs?  

These initial programmes confirm the cost control that could be achieved through low-carbon construction. By using Hoffmann’s H-UKR cement technology, the additional cost for our main construction work is under €450 per unit for our 103-unit assisted living residence in Sablaise!

As an indication, notwithstanding structural constraints, the use of wood was 4 times more expensive! These new cements also have a significant “field” advantage for our companies. Practical implementation is unchanged. We use the same processes and tools as for traditional cement. Low-carbon implies a complementarity of materials that has very little impact in the end on overall programme cost for us as a developer. 

Batignolles 2020, ecological pioneer

Can you tell us more about the Batignolles project? 

The Batignolles district is an ambitious project, since it aims to build the first low-carbon district in Europe! After the recognition of Nantes Métropole PLUM (metropolitan local urban plan), we are launching the construction of a first phase of 20,000 m2 of housing and 9,000 m2 of tertiary buildings. Our slogan for this programme: Batignolles 1920, industrial pioneer, Batignolles 2020, ecological pioneer. For the past two and a half years, we have been working with FORMA6 and TETRAC which have helped promote many projects in Nantes.

The goal is a big-picture view of the district: what it was, is and will be. The highlight is the creation of a Green Label Alliance Hub, which brings together the history of the Batignolles, but also the technologies of those companies that will participate in developing this district and setting up a full-scale laboratory for low-carbon applications. Beyond its purely ecological aspect, this project must be societal. Consultations and presentations on the project will be held with inhabitants in the district and more broadly in all of Nantes. A first presentation of the project will be made at the end of the first half of 2020. 

This interview is taken from pages 18 & 19 of our magazine ForHum, currently available for free consultation on our website.