Eco-design of buildings and urban districts

Ecodesign involves taking environmental aspects into account in the design and life cycle of a product. This article deals with the application of this approach to buildings and neighborhoods.

The objectives of preserving the climate, human health, biodiversity and resources are widely shared. In this context, eco-design makes a contribution through a preventive approach. It involves guiding decisions from the design phase of a building project, even before it is built, with the aim of reducing the environmental impacts over its life cycle, as well as the social consequences and costs induced by these impacts. This preventive strategy also makes economic sense, as intervening upstream is less costly than correcting design errors once the building has been constructed.

Decision-makers' awareness of environmental issues has given rise to a number of initiatives, such as the development of a "high environmental quality" approach for buildings and the creation of numerous "eco-neighbourhoods", although the corresponding concepts are not always precisely backed up. Yet the scale of the risks, from local to global, calls for more rigorous management of these issues. Urban planning decisions have a strong influence on the building and transport sectors, which are major contributors to most environmental impacts.

In France – and Europe –, for example, the building sector is the biggest energy consumer, accounting for almost half of total consumption, twice as much as industry. Direct consumption of drinking water accounts for around 20% of net water consumption, but an equally large quantity is used indirectly to generate electricity, 60% of which is consumed in buildings. Between one and two tonnes of materials are used per m ² built, making the building industry one of the largest outlets for industrial products. 40 million tonnes of waste are produced every year on demolition, rehabilitation and construction sites, compared with 28 million tonnes of household waste. Building-related pollutant emissions are very high, both in the air (22% of greenhouse gases, for example) and in water (a quarter of phosphate equivalent discharges). It is therefore essential to mobilize all professionals in this sector to preserve future generations and biodiversity.

The concept of sustainable development was originally defined as satisfying the needs of the present while preserving the interests of future generations (Brundtland report). It is not, therefore, a vague compromise between economic, social and environmental aspects, as is too often understood today. Satisfying the needs of the present would mean, for example, meeting a largely unsatisfied demand for housing that meets certain standards...