In the building and public works sector, eco-design is gaining ground. It is a topic of discussions, some actors are getting ahead. But obstacles are emerging, some regulatory, others economic. An industrial chair dedicated to this subject, bringing together a manufacturer, the Vinci group, and three engineering schools including Mines ParisTech, aims to advance thinking and disseminate methods.
Eco-design is gradually integrated into construction practices, but it is not yet part of the industry culture. One reason for this is that the sector is highly compartmentalized, particularly between design and implementation. It is mainly on high-rise buildings and large facilities, where the market is highly concentrated, that the choices of the sector's major players become normative. Elsewhere, instead of coordination one sees the rise of experts. The core business of the manufacturer consists in assembling heterogeneous elements. How to eco-design this assembling? The Industrial Chair "Eco-design of buildings and infrastructures" attempts to answer this question with integration tools, in order to evaluate and optimize the overall eco-design of the integration of different parts of work. This integrative approach responds to a specificity of this industry, but it is also in phase with the heart of the idea of eco-design, which consists precisely in not sticking to a product but integrating its upstream and downstream. This perspective, which involves a reflection on uses, is to be distinguished from two impasses: the confusion between eco-design and energy saving, on the one hand, and the abstraction of the current regulatory approach, on the other. Working from life cycle analysis helps to avoid these shortcomings. But for some trades this is hardly useful. Rather, these tools should probably be part of a multi-criteria decision support approach, based on the notion of life cycle thinking, which would really bring together all the players around the same tool.
Christophe Gobin - This is a long process of maturation, dating back to the early 1990s and not complete yet. Eco-design is gradually becoming part of our industrial culture, but it is not yet fully integrated. The concept of available budget and the financial dimension remain central. Eco-design is still an element of appreciation that comes in addition, and not a mode of reasoning prior to any project.
One reason is that the construction sector is very compartmentalized, particularly between design and construction. Major companies are very reactive. But the value chain is fragmented and each actor in the chain tends to optimize its own logic, sometimes shifting externalities onto other segments of the chain. Moreover, in the building industry, the building owner and the production companies are in parallel worlds. They can associate for a given project, but there is no coordination in the true sense of the word, as in the industry, where there is continuity in decision-making.
This is a problem around the world. In France, since 1945, the law prohibits that a master builder, architect, is incorporated in the production. Legally, design is independent of production. The underlying idea is that the profession of architect is of public utility, therefore independent of any economic pressure.
We have to put the market in perspective. If you take France, where major players such as Vinci, Bouygues and Eiffage have developed, they collectively account for only 30% of the market: they therefore have little capacity to drive a sector that is still largely dominated by very small companies. It is mainly on high-rise buildings and large facilities, where the market is highly concentrated, that the choices of the sector's major players become normative.
Nor should we imagine that large companies have networks of loyal partners that they could train in new methods. The construction sites are so scattered that each time we have different partners.
Rather than coordination, the expert business is flourishing. One characteristic of our industry is that, when a new problem appears, a new profession is created. Environmental problems have therefore led to the emergence of specialized design offices and project management assistance consultants. But it is a bit absurd: we reify a problem rather than integrate it into a collective approach. We rely on a new specialist: we outsource. At the macro level, it is counterproductive - not from the company's point of view: we are used to working with consultants. But for taxpayers (public works) and consumers (building), it is an extra cost.
In our sector, the concept was first deployed among component producers, with the challenge of reinforcing a product by recognizing the existence of an environmental dimension. Regulatory developments may have contributed to this. In industries around housing, consumers can be sensitive to these issues. The construction industry therefore began to develop products whose design integrated environmental issues: glazing, insulation elements, and even concrete.
In the construction business itself, the problem is that we do not have a repetitive object: you don’t replicate a building. Finally, the core of our business consists in assembling heterogeneous elements. How to eco-design an assembly of heterogeneous components? That's an exciting question.
It was precisely to develop relevant responses that we launched, with Mines ParisTech and two other engineering schools (Ponts ParisTech and Agro ParisTech), the "Eco-design of buildings and infrastructure" industrial chair. The tools developed by the Chair are integration tools. We do not design glazing, concrete, floor coverings. But we have tools to evaluate and optimize the overall eco-design of the integration of these different parts of work. This integrative approach responds to a specificity of our business, but it is also in phase with the heart of the idea of eco-design, which is precisely not to stick to a product but to integrate its upstream and downstream. As a result, while construction is rather behind the industry, on the eco-design side we have taken the lead.
At present, however, there is a tendency to confuse eco-design with energy saving. It's a shortcut, and it's counterproductive. Similarly, the current regulatory approach - RT2012 in France - seems very abstract to me. It allows a building to be evaluated according to certain criteria - for example, a "low-energy building" is designed to consume 50 kWh/m2/year. But this regulation tends to ignore actual usage. It's a legal fiction.
Industrial functional analysis can offer solutions: the functional approach translates into the ability to enable an activity. This activity will be measured by a number of criteria which, when quantified, will become performance - surface, volume, ventilation, acoustic comfort, protection, safety, relationship to others. Performance is multidimensional. Performance is the quantification of all usage functions.
We can go further: with Mines ParisTech, we are working on scenarios of how places are used. This requires assumptions to be made about users and, more broadly, lifestyles. A very simple example: the 2012 RT assumes that a residential building is occupied until 9:30 am, then from 9:30 am to noon people work and there is nobody at home, so the temperature can drop, in winter, until 14°C. But if there are a couple of elderly persons in the building, they will ll get cold!
Scenarizing uses does not require going very far in sociology, nor to have typologies of uses, but to question real uses, instead of constructing a theoretical protocol on an average use. A building is a complex object, and it is this complexity that we must try to understand.
It was precisely the example of services that made it possible to launch the first reflections on eco-design in construction in the early 1990s. Our discussions with the Ecole des Mines go back to 1992: this year refers to the Earth Summit in Rio, but for us it is also more modestly an invitation to tender from the Ministry of Public Works, which asked the major players in the sector for their ideas to deal with the environment. Something was moving. The services, around our sector, had started to initiate eco-design approaches. It was in this context that we got in touch with Ecole des Mines, and very quickly we concluded that the construction industry, like the other sectors, would make progress on environmental issues only if measurement tools could be developed.
At the time, "high environmental quality" (HEQ) proposals were beginning to emerge, opening the way to regulation with multiple targets. With my partners at Ecole des Mines, we thought that we should be more demanding and prefer scientific measurement to simple compliance with regulations. This reflection finally found a more formal framework, when around 2007 the opportunity presented itself to concretize this intellectual and scientific connivance within the framework of an institutional partnership, which was the Chair.
Why a chair? We thought that this framework would give us the opportunity to introduce, through public sponsorship, measurement tools and have them recognized by the Ministry, whose culture was not that of measurement and performance, but that of standards.
What is interesting is that the work carried out by the Chair has led the other branch, that of HQE and regulatory standards, to the idea of measuring performance. It was only around 2010 that the regulatory approach began to favour the notion of performance, which led to the RT2012 issued by the Ministry.
But the standards-based approach is necessarily a bad rating, given the complexity of projects and the difference in context and uses from one project to another. As long as we don't have tools to measure results, as long as we don't have mathematical modelling tools that integrate uses, we don't do eco-design. The only standard we could have is the obligation to do a life cycle analysis, without setting thresholds a priori.
Eco-design per se is bioclimatic architecture, reasoning on volumes, etc. It is at the heart of the architect profession: in the past, architects used to fit their buildings into their environment, they used local materials, they were not yet limited to drawing ! They had this concern for the environment, which got lost in the 20th century. Today we return to the sources: eco-design is the art of building well. But we are in the 21st century, we have sophisticated tools, and we can therefore objectify the environmental consequences through a tangible measurement tool. This is precisely what the Eco-design Chair is working on.