Towards a pre-design method for low carbon architectural strategies

To face climate change, Switzerland proposes the 2050 energy strategy by fixing greenhouse gas (GHG) emission targets for the built environment. Designers will then have to increase operating performances while inimizing embodied impacts. This represents an issue for the building design process. In addition, there is a relationship between the design efficiency and the early integration of the knowledge about design. The purpose of this paper is to highlight the potential of a pre-design method to identify the building design parameters that reach the 2050 climate change objectives. To that end, four major steps are developed in this project. First, design parameters (e.g. wall thermal transmittance) which influence the building GHG emissions the most, are identified thanks to a literature review. Morris method (Saltelli et al, 2004) is used to create combinations of design parameters changing their values one by one. Secondly, these combinations are attributed to architectural feasibility studies (Sinclair, 2013) developed in the brief design phase to perform lifecycle analysis. Thirdly, KBOB database (KBOB et al., 2014) and lifetime of components proposed by PI-BAT were used for assessing GHG emissions. Lesosai software was used for primary energy assessment. Lastly, the combinations of design parameters and their relative GHG emissions are interpreted with data mining and visualization techniques. The smart living lab building has been chosen as a case study: this building aims at achieving the 2050 goals of the 2000-watt society vision and will be built by 2020 in Fribourg, Switzerland. Thanks to the preliminary results it is possible to rank the design parameters according to their GHG contribution, in order to highlight them during the early building design stage. The method offers combinations of design parameters allowing to reach the 2050 climate change objectives. Data mining and visualization enable designers to easily find the values of these parameters to fit into the architectural strategy. In order to offer a wider range of design parameter values, techniques to enhance the database should be further investigated.

Intégration des critères de durabilité dans le processus de conception des constructions temporaires à vocation événementielle

Loïc Vivien Fumeaux

Sustainability is a constant search for balance between the needs and the means implemented, which implies meeting the needs present without compromising those of generations to come. Later generations will indeed imperative to consider. So that their scope for action not be mortgaged by human activities of previous generations, it is necessary to provide some leeway, especially from the perspective of the built environment transmitted by inheritance. Alongside these general theoretical considerations, it is now observed a glaring mismatch between the rapidly changing socio-cultural practices and the very slow renewal of the built environment . Whether in the way to live or work , or occupy constructed in the need for research space flexibility , the frame is characterized by the notion of "impermanence" increasingly important, in contrast with the perennial character commonly accepted and implemented in current practices . Most buildings are built to last, but are part of a society where everything is changing rapidly and so are facing frequent shifting situations between form and function of spaces. In this context, the temporary architecture can therefore be a good potential to seek to meet the challenges of multiple time frames and offer a potential mutation. This architectural approach is thus fully in sustainability concerns mentioned above, since it aims to offer a potential for adaptation rather than fixed solutions. Aware of the extent of the issue and complexity of reflections on the question of the impermanence of the frame, especially in view of the nature of architectural practices, this work focuses specifically on a little explored area that day at the research for which the notion of temporality is short intrinsic data: the field of temporary constructions events vocation. Through an exploratory approach, research methodology convene an archetype of the temporary architectural design to examine it as an object of study that can ideally translate the challenges of a design associated with an approach based on time restricted use. The research first observed in detail these practices sometimes considered at the margin of the architectural discipline. The structured analysis of four representative case helps highlight their limitations in terms of sustainability. part of the research, evaluative approach includes the development of an assessment methodology, specifically adapted to this type of construction. The approach then proposes the development of an alternative solution, which optimizes its multiple performances in a perspective of sustainability and overall quality. Through an approach of "research by the project" an integrated design process (IDP), both interdisciplinary and participatory, is experienced first sketches to detailed development of a prototype. Finally, from the product of this reflection, research in general rises and explores many possibilities of using this new system. This approach allows to demonstrate the potential contribution of multiple functional areas, illustrating what could be the conceptual foundations of an "architecture of the event." The result is a research methodology both "multi-scale" and "multidisciplinary", which demonstrates the great potential for optimizing this type of construction and the need to achieve to grasp the design simultaneously at multiple scales and integrating all stakeholders.

EPFL2016

Data-driven method for low-carbon building design at early stages

Thomas Bernard Paul Jusselme

The Paris agreement on climate change called for carbon neutrality as of 2050. The built environment is one of the major contributors to the greenhouse effect, representing 39% of global emissions. As a result, this sector is targeted by green standards and regulations to set limits for building carbon emissions. Life Cycle Assessment (LCA) is widely recognized as an appropriate method to measure these emissions. This is particularly critical at the early design stage where the decisions that most influence the project are made. However, previous studies show that current LCA methods, both time-consuming and requiring a high resolution of detail, are most inadequate, which makes them too rarely used by practitioners today. This thesis aims to tackle this issue by proposing a novel approach to LCA adapted to the early design context. The first step was the identification of obstacles responsible for the current low use of LCA. This analysis was based on an extensive survey about the practice of 500 architects and engineers in Europe. Secondly, a literature review identified four appropriate techniques to overcome these obstacles: parametric assessment, sensitivity analysis, target cascading and data visualization. Combining them to the LCA led us to the data-driven method for low-carbon building design at early stages we adopted in this thesis, removing the need to set premature assumptions about future design developments. The method proposes a knowledge-database of design alternatives generated with a parametric approach that applies a combination of user-defined design options, using the Saltelli sampling technique, to a project-specific massing scheme. Later, the carbon emissions of each of these design alternatives are calculated. It is thus possible to explore thousands of alternatives and understand the consequences of architectural choices on the carbon emissions by using data visualization techniques. Moreover, the method proposes Sobol sensitivity indices quantifying the design parameter influence on the carbon emissions, in order to limit the scope of building components that designers should prioritize. Finally, the method specifies carbon budgets, the upper limit of carbon emissions a building component should not exceed, with the possibility to compare this budget with any product available on the market that would not have been included upfront as a design option in the parametric approach. To assess the usability of the method, a computer-based prototype was thereafter developed to get it tested in the frame of a real design project. By taking advantage of the architectural competition for the Smart Living Lab in Fribourg, Switzerland, this critical testing phase was carried out by asking the practitioners involved to actually use the developed prototype to meet the SIA2040 carbon objectives set for the project. This thesis proposes a new method for effectively integrating GHG emission targets into the early stages of the design process with the aim to increase both acceptance and use of LCA in the design field, but also to inspire developers towards a new generation of LCA software.

EPFL2020

Application of the Cradle to Cradle paradigm to a housing unit in Switzerland: Findings from a prototype design

Marilyne Andersen, Shady Galal Mohamed Attia, Jean François Bernard Beney

The Cradle to Cradle (C2C) paradigm is emerging as an important regenerative design approach. C2C is aiming to create a positive footprint of the built environment, beyond carbon neutrality. However, there are very few studies that address the application of the C2C concept in building design. More importantly, there is hardly any documentation processes on methods or tools currently being used to design and evaluate C2C buildings. Therefore, the purpose of this paper is to design, model and assess a C2C building prototype with a focus on energy and materials. The research methodology is based on literature review, case study design and performance (energy/materials) evaluation (DesignBuilder/SimaPro). The paper articulates the values, principles and goals of the C2C paradigm and translates them through the prototype design in the Swiss context. The results of the prototype design point to a 74% independence from non-renewable energy resources, compensating the operating and embodied energy during the building’s life. On the other hand only 8% of the building materials were totally recyclable according to the C2C principles. The design process delivers insights on the application of the C2C concept in the built environment reporting on the limitation and means of improvement.