Research
The chair has been working on the implementation of sustainability practices in the profession, on the development of alternative building materials as well as looking for building bridges between a local practice and a global knowledge.
1. Ground sustainability in planning and construction phases
Ground LCA with architects and decision makers: LCA is often done at the end of the construction project when rooms for improvement are small. But in the early design phase the amount of information is reduced and reliable decision might be difficult to take. Our work aims to provide tools so that decision makers can take informed decisions all along the design process. Recent combine LCA and design tool using parametric LCA strategy and develop a LCA module that can be uploaded in design software tools for architect. (external page https://doi.org/10.1088/1755-1315/323/1/012112)
Ground LCA with construction companies in emerging countries: The main bottleneck is the lack of database, the high level of informality and the low amount of investment and standards. Our focus is to simplify LCA. Reduce the number of indicators as well as the amount of flows to be measured by construction companies without losing accuracy in the results. This is done through statistical analysis and development of appropriate database. (external page https://doi.org/10.1016/j.jclepro.2014.01.067)
Ground resource efficiency in current construction value chain: Our studies show that savings achieved by the cement and concrete construction industry with a more integrated and circular value chain are significant and can allow, in Europe, to meet 2050 objective of the Paris agreement. The current work engaged is now is to find the right business models to transform the construction industry. (external page https://doi.org/10.3929/ethz-b-000301843)
Ground social consideration in conventional cost calculation: Most decision are taken considering costs calculation and very seldom the consequences (positive or negative), spending can have on the surrounding society. Our strategy is to localize the costs of construction by stakeholders, by geographical location and by nature (energy, labour, taxes). This representation of the economic costs is able to draw a picture of the consequence of construction project that directly speak to decision makers. This work is applied on formal as well as on informal settlements and conducted in collaboration with ICRC and UN Habitat on slum upgrading programs. (external page https://doi.org/10.1080/09613218.2017.1294419)
2. Ground sustainable building technologies in construction practices
Ground earth construction in current construction practices: Working on earth is a major focus on the material development in the chair. We are developing a material that can be casted like concrete, using same processing technique and nearly the same speed of construction. We are particularly interested by questions related with variability of earth, water resistance, shrinkage and mix design. (external page https://doi.org/10.1016/j.colsurfa.2017.12.040)
Ground low carbon cementitious materials in construction: In Ordinary Portland Cement, the clinker is the active component, which provides strength, but it can be combined with a multitude of alternative materials and form a cementitious binder with much lower environmental impact. The interest of these low carbon binders is the ability to implement them easily in the field as it is just a change inside the cement bag and all the rest of the construction practice would stay the same. (external page https://doi.org/10.1016/j.jclepro.2016.02.125)
Ground the use of Biomass material as temporary carbon storage: Current method to calculate the environmental impact of biomass fail to grasp the potential these materials can provide fro mitigating climate change. We worked on advanced LCA methods and applied them on various building stocks (EU, South Africa…) to show what different policy decision can triggers in term of carbon storage in the building stock (external page https://doi.org/10.1016/j.buildenv.2017.12.006)
Ground digital fabrication in a changing and uncertain world: The main question is how digitalization can help to build a sustainable construction. We first identified that digitalization can reduce environmental impact compared to conventional construction if the structures built are structurally optimized, but also if the complexity of the built element allows a multi-functionality of the element. However, the limit is the robustness over the time as it is difficult to combine multi-functionality and flexibility of use. To overcome this problem, we are developing 3d printed building materials allowing both structural performance and moisture control in a very simple and robust way. (external page https://doi.org/10.1016/j.cemconres.2018.06.001)
3. Building bridges between local practices and global knowledge
Men and women have use local materials and developed their own building techniques over the last 10’000 years and many vernacular practices could be used to solve our current challenges. They often lack rigorous evaluation of their efficiency, which hinder their development. Our strategy is to first identify this local knowledge. Then conduct scientific studies in order to understand the mechanisms involved and measure the efficiency of these technologies and finally, perform retro engineering in order to be able to use not necessarily the vernacular practice as such, but the knowledge embedded into this vernacular practice for more contemporary engineering practices. (external page https://www.researchgate.net/publication/336363141_CSA_as_A_Revisited_Vernacular_Technique_for_Earth_Stabilization)