Sustainability has to be thought at each phase of the project:
- Raw material acquisition and processing
- Manufacture and assembly
- Use and service
- Retirement and Recovery
- Treatment Disposal
A building will have achieved sustainability if it manages to do so at each phase of the project.
The choice of material at the beginning of the project has to be done so that the construction phase has the less impact possible but also prepares for the building to be efficient during the use phase.
To reduce the construction phase impact, more and more buildings use wooden structures. For instance, for the Olympic Village of Paris 2024, an agreement was signed imposing that all the buildings lower than 9 stories are to have a wooden structure.
The use and service phase impact can be reduced by using materials and designs that makes the building more thermically efficient and that encourages the use of sustainable resources. The main challenge is to be able to take advantage of the environment surrounding the building to maximize the efficiency.
An example of that is the Bahrain World Trade Center 1 and 2. The design of the building is optimized so that three wind turbines are perfectly positioned to generate electricity. Reflective pools were also put at the base of the towers to help cooling via evaporation.
Another inspiring example is the Marco Polo Tower in Hamburg. Each floor of the apartment building is turned a few degrees compared to the previous one. This contributes to reduce the sun’s impact during summer.
An idea could be to optimize the façade of a building so that the sun enters directly through the glass façade in the winter to limit heating but that is still in the shadow during the summer to limit air conditioning.