New environmental requirements, new ways of working, new materials… The construction and public works sector is developing simultaneously with society’s expectations, revolutionizing all methods and tools. Here is an overview of the efforts made by this rapidly changing sector.

Written by Christophe Frapelle

Far from the image of a static sector, the construction industry is doubling down on its ingenuity to meet the new demands of the 21st century and confront the increasing complexity of construction sites.

To meet these new challenges, sector players have developed new tools and new ways of working. Multiplication of experience and professions, growing practice of joint activities, turning to groupings of companies… These upheavals are necessary both to reduce costs and deadlines, but also as a means of integrating new CSR standards into the entire value chain. The construction industry also makes significant efforts to solve environmental and social problems. Protection of biodiversity, use of new, less polluting materials, reduction of nuisance for local residents… Players of the sector strive in every way to reduce their impact on the climate and the living world.

Concrete, in the center of all worries

Concrete, used in all modern buildings, is one of the main levers for reducing greenhouse gas (GHG) emissions in the construction industry. Globally, concrete alone is responsible for 7% of greenhouse gas emissions! In particular, a component used in cement production is to blame: clinker. As it heats up, it ‘decarbonates’, releasing large amounts of greenhouse gases. About 800 kg of CO2 is emitted for each ton of cement produced.
Many companies, such as LafargeHolcim, Cemex and Calcia, offer “low-carbon” concrete mixes that have a lower clinker content. “These specific ranges guarantee the same qualities (strength, hardness, etc.) as normal concrete. But the share of clinker is decreasing and being replaced by other resources available in the regions, such as blast furnace slag or fly ash from thermal power plants,” explains Florent Dubois, head of construction at LafargeHolcim.
However, French start-up Hoffmann Green Cement Technologies goes further by offering unfired and clinker cement. This formula is so revolutionary that it has attracted the attention of several major French construction companies, including Demathieu Bard, Eiffage and Nivet, who have already added to the Vendée startup’s order book. Eiffage has said it wants to use this ultra-low carbon cement to build the Ateliers Gaité on Montparnasse in Paris. The Nivet group, for its part, wants to use cement produced by Hoffmann Green for the ready-mixed concrete market.
Finally, more and more builders are also promoting the concept of a “material mix”, which consists of using recycled or bio-based materials as a priority. The new ‘RE2020’ building code, which came into effect in January 2022, specifically favors materials that store carbon rather than emit it, such as wood. An emblematic example of the combination of materials, the Hyperion Tower, built in Bordeaux by Eiffage, was built with a concrete core and solid wood floors. The builder estimates that the use of solid wood has reduced the site’s CO2 emissions by 25%. The Hyperion Tower, due for completion in 2021, is one of many examples of the construction industry not waiting for legislation to change before adopting new, greener construction methods.

Noise pollution, protecting biodiversity…: the construction industry is mobilizing to reduce its negative externalities

However, environmental protection is not limited to reducing greenhouse gas emissions. This is why the construction sector has been striving for several years to minimize its (many) negative externalities, both those that harm the peace and quiet of local residents and those that can have a lasting impact on ecosystems. Impacts on biodiversity and noise pollution are major societal concerns, and most companies make this a focus of their efforts in their workplaces.

Noise is one of the issues most studied by construction companies. This problem arises in particular when they are working in densely populated or sensitive areas such as the city centre. The engineering company Ingérop was surrounded by acoustic consultants for the Les Halles project in Paris. The work of these acousticians consisted of developing recommendations to reduce noise pollution caused by work, for example, by recommending the use of noisy tools at the same time or installing an alarm system for trucks whose engines were not turned off. Moreover, more and more companies are no longer using the “reverse horns” of construction equipment, which are particularly annoying to local residents and operators, and have replaced them with the “lynx cry”, which is characterized by the fact that it is almost inaudible outside the car. reverse axis.

Regarding biodiversity protection, many companies in this sector have joined the U2B (Urbanism, Building and Biodiversity) club founded by the League for the Protection of Birds (LPO). Meeting four times a year with all its members participating, the Club raises awareness of biodiversity in the city, artificial turf and the dangers of glass surfaces to birds. The LPO also sometimes specifically advises construction companies, providing technical advice. For example, Eiffage Aménagement received help from the Association for the Protection of Biodiversity in the construction of the LaVallée eco-district in Chateauneuf-Malabry. This personalized support consisted of information training for construction teams, particularly on the integration of biodiversity into buildings.

Although these changes in environmental practices and attitudes are welcome, their actual application by all players on the construction site is far from obvious, especially in a sector with such a wide variety of companies… However, these new CSR rules and standards may well help their application a parallel evolution of working methods in the construction industry.

When companies join forces to meet the new challenges of the construction industry

As construction sites, projects and technologies become more and more complex, players in the construction industry are forced to diversify their expertise and professions to provide a more complete offer.

This proliferation of professions and methods has led to the revival of temporary groupings of companies (GMEs), which allow several companies to submit a joint bid for the same tender. These groupings have become the norm for highly technical and multidisciplinary projects, such as the many Grand Paris Express (GPE) projects, which require a wide range of expertise and where deadlines are even more challenging.

Indeed, one of the most obvious advantages of consortia is that they facilitate the practice of joint activities as a method of reducing deadlines. When several companies and subcontractors from the same group work simultaneously in different sectors of the same site, construction companies can save valuable time. “General terms of operations [of the Grand Paris Express, editor’s note] created the need to set up joint activities on the current sites,” explains Pascal Hamet, Project Director of Lot 1 Line 16 at Eiffage Infrastructure. “We are making areas already completed by Eiffage Génie Civil available to external contractors, some of whom are from other Eiffage branches. In fact, when a company has several skills at its disposal, joint activities are optimized by the habit of working together, which, in particular, allows quick decision-making in situations of danger. This approach to construction sites has already been tried and tested by the French group on another major project, the Brittany-Pays-de-la-Loire high-speed rail line, where Eiffage was able to organize the work of its civil engineering, rail transport, energy and Systems subsidiaries to meet deadlines. , set by the project owner.

However, as mentioned above, consortia also have other, less obvious advantages. Indeed, as they bring together a wide variety of companies (large groups, ETIs, SMEs, etc.), groupings also contribute to the coherence of environmental and social rules, norms and standards. This makes it possible to spread these good CSR practices widely among all the companies involved, who can then appropriate them and quickly apply them to other projects. It is a way to irrigate the entire value chain using new methods that meet the most demanding standards.