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The aim of this project was to investigate and quantify the impact of certain early design decisions on the solar potential of a target building placed in an urban context. This was done through a parametric study based on the successive variation of specific design parameters: building height, distance, reflection and orientation. A Design of Experiment (DoE) approach was adopted with a 2-level fractional factorial design. For each new 3D model obtained, an irradiation simulation was conducted for the climates of Geneva, Phoenix and St. Petersburg. Results were processed to identify the main design parameters of influence, quantified by the main effect and percentage contribution, and interpreted through various representations such as irradiation maps and DoE mean plots. Results showed the main influential design parameter to be, for all climates, the height of the surrounding buildings, followed by the distance between the central and surrounding buildings.

The challenge is to provide information about visual comfort and energy savings potential on an annual basis while daylight is dynamic, and the interaction between daylight, the façade and the indoor material is complex. A new approach has been build to assess the performance of light-interacting façades and indoor coating. This approach led to an annual climate-based simulation which allows to assess the performance of systems for the whole year. Furthermore, the approach makes it possible to deal with complex façade systems because it integrates the Dynamic Radiance method and its BTDF matrix. The complexity of such a matrix has been tackled by a stereographic representation which give an comprehensive overview of the façade behavior. Thank to this, results are easier to understand and visualize. This work shows why the design of a façade and of its associated indoor coating are strongly coupled. A coating optimized for on system will not fit with other systems, and vice versa. A balance between light diffusion and light conduction must be found for every new façade. To move further, new metric evaluating the coupling and the performance of a façade system can be imagined. It would be based on the sensibility of the system to the properties changes of its associated indoor coating. L’enjeux est de fournir des informations sur le confort visuel et le potentiel en économie d’énergie à l’échelle annuelle car la lumière naturelle est dynamique, et les interactions entre la façade est le revêtement intérieur sont complexes. Une nouvelle approche intégrative a été mise au point pour évaluer la performance des façades complexes et des matériaux intérieurs. Cette approche permet de réaliser des simulations annuelles basées sur le climat. De plus, cette approche permet de traiter les façades complexes par le biais de leur BTDF, ce qui est rendu possible par la méthode Dynamic Radiance, qui a été intégrée dans l’approche in- tégrative développée ici. La matrice des BTDF utilisée dans cette méthode a été rendu plus claire grâce à une nouvelle représentation stéréographique qui permet d’avoir un aperçu complet du comportement d’une façade. Ce travail montre combien la conception d’une façade est intimement liée à celle du revêtement intérieur qui lui est associé. Un revêtement bon pour un système de façade ne le sera pas forcément pour un autre système, et inversement. Pour aller plus loin, on peut envisager de mettre sur pied une nouvelle métrique qui viendrait évaluer le couplage d’une façade avec son revêtement intérieur et par là-même sa performance. Cela reposerait sur la sensibilité du système de façade aux changements de propriétés du revêtement intérieur qui lui est associé.

Windows in workplace environment are desirable for their several proven physiological, psychological and economic benefits. Daylight from windows is also responsible for glare which can cause occupants to close the blinds. Glazing properties of the windows play a key role in defining the quality and quantity of the transmitted daylight in a space and therefore controlling glare. With the current trend of colored glazing such blue electrochromic glazing, colored PV panels, dye-sensitized solar cell glazing, it is essential to know the effect of altered spectrum of daylight on glare perception which has not been studied yet. Towards this end, we determine for the first time whether the spectrum of daylight glare source (i.e. the sun) altered by colored glazing influences human perception of glare in workplace scenarios following a psychophysical procedure. We designed a controlled lab study with 50 participants experiencing glare under red, blue, green and grey (color-neutral) colored glazing in an office-like test room with sun behind the glazing as the only glare source. The study was designed as a combination of within-between design where color of glazing was changing within participants and transmittance of glazing was changing between participants. Each participant was exposed to all four colored glazings with similar visible light transmittances resulting in exposure to similar levels of glare metrics values and the color of glazing was the only variable within the tested scenes. Two levels of glazing transmittances (τv = 0.3%, 3%) were tested under all four colors with 25 participants under each transmittance. Results indicate that there is an influence of color on participants perception of glare independent of transmittance. We found that the participants experienced statistically much higher levels of glare under red glazing followed by blue glazing and least discomfort under grey and green glazing. These results indicate a clear effect of color or glare source spectrum on glare perception and calls for an update to glare metrics to include this effect to account for the differences in perception of glare. Results further indicate the inapplicability of photopic luminosity function V () in quantifying luminance for brightly lit saturated colored glare sources.

Since the second half of the XX century, the way new urban areas have risen next to the ancient/traditional parts of cities has been vastly unsystematic, often altering the original natural landscape and/or urban morphology significantly. This has sometimes generated a mixture of architectural languages and technologies without any regard for the connectivity of a community as a whole. Despite the revival in current design practice of passive design solutions, studies on the influence of contemporary urban settlements on the thermal behavior of traditional buildings are still very limited. The aim of this study is to investigate, through simulation-based assessments, how contemporary urban settlements and buildings affect the bioclimatic features of existing historic architecture. The analysis considers some case studies located in different countries and climates and moves from a micro-urban to a building scale.

The project goal was to assess the viability of photovoltaic (PV) installations in two different existing buildings, both located in the city of Neuchâtel. The two studies buildings were built in 1938 and 1968. Before testing any PV installation, a renovation of the envelope were proposed in order to achieve a high level of energy performance. Indeed, the two buildings require a large amount of energy for heating due mainly to the low performance of the existing envelope. Different scenarios were tested considering the legal requirements in Switzerland (SIA norms). In addition, their cost-effectiveness was assessed. After the implementation of a passive renovation, improving the energy performance of the building envelope, a scenario integrating PV elements on roof and facades was assessed. Different configurations were tested, in order to improve the energy balance on the building taking into account the on-site energy production. Finally, a comparison of the results from both case studies was conducted.

This research project deals with the suitability of the program Radiance for detailing the spectral qualities of the light received inside a room. More specifically, it asks whether Radiance’s innate RGB algorithm can be used to accurately determine the nonvisual effects of light on viewers in the space, particularly when also considering the view direction of the sensor. It goes on to explore whether there is a simple method to modify the results produced by an RGB-type simulation to more closely match more accurate methods. The experiment compared several simulations, all measured from a viewpoint at the center of rectangular room with a single window on one side. The interior color of the room was varied, while the color cast of the sky and ground remained constant. Eight vertical (facing toward the wall) view directions were simulated. For each color condition and viewpoint, the RGB simulation was compared to three other simulations that represented the spectrum using a different method, averaging the reflectance over three, nine, and twenty-seven spectral intervals between 380 nanometers and 730 nanometers. The Radiance program produced three irradiance values for the RGB and three-interval simulations, nine irradiance values for the nine-interval simulation, and so on, which could then be used with the visual and circadian sensitivity curves to calculate visual lux and circadian lux.

This poster exposes the outline of the PhD research project of the main author (E. Nault), which focusses on improving the solar potential of neighborhoods at the early design phase and through an interactive design support methodology.

Situé à proximité du centre de Neuchâtel, ce nouveau bâtiment termine un îlot existant et s’inscrit dans un schéma plus large de requalification d’une partie du quartier. La surface est principalement occupée par des logements mais accueille également des activités, notamment liées au domaine de la santé, en synergie avec l’hôpital tout proche. L’exposition au rayonnement est un sujet d’inquiétude pour une partie de la population et ce bâtiment veut proposer un cadre de vie agréable et sain dans un contexte urbain, pensé pour les personnes sensibles à cette problématique. D’autres éléments de confort sont également pris en compte, tels que la limitation de l’exposition au bruit, l’apport de lumière du jour ou la réduction des émissions chimiques dues à certains matériaux. Deux identités différentes caractérisent le bâtiment: une façade extérieure continue et une cour intérieure définie par les plateaux des étages. L’organisation autour d’une cour fermée souligne cette recherche de calme et de protection. Le plan présente une claire séparation entre les espaces isolés du rayonnement et ceux où la présence des ondes est acceptée. Des noyaux aux murs massifs pouvant absorber le rayonnement abritent les lieux protégés, contenant en général une ou deux pièces desservies par un sas. Ces noyaux protégés, colonnes traversant tous les étages, génèrent par leur disposition les espaces de séjour, interstitiels. Ils constituent en outre la structure porteuse de tout le système.

Designing architectural façades that allow sufficient daylight to create visually comfortable and pleasant environments is a challenging aspect of building design. It requires accounting for visual comfort and discomfort glare risks and understanding the factors that influence them. In the last two decades, several prediction models have been developed to quantify discomfort glare by considering almost exclusively the photometric properties and spatial distribution of incoming light. Although these empirical models have been derived to best match one's perception of glare, they fail to account for the significant interindividual variability that exists in glare perception and are furthermore limited in their applicability in certain visual environments. It is evident from the literature that not all the factors influencing discomfort glare perception are known and accounted for in the existing prediction models. Based on the literature review, we have identified two potential factors, namely, the macular pigment density in the retina and the color of daylight, as likely to influence discomfort glare perception. Up to now, their influence on glare induced by daylight has remained unknown. To address this gap, this thesis aims to determine the influence of macular pigment density and color of the sun disc (altered by colored glazing) on discomfort glare perception in daylit environments. By means of three psychophysical experiments conducted in office-like test rooms along with the ocular examinations of the participants, we determined the influence of macular pigment and color of daylight on the perception of discomfort glare for young and healthy individuals. Three experiments were conducted, one with blue electrochromic glazing, one with color-neutral glazing, and the third with red, blue, green, and color-neutral glazing. Each experiment followed a similar protocol of exposing every participant to four daylight glare scenarios and recording their responses to questionnaires. The four daylight scenarios differed either in color or in the transmittance of the glazing through which the sun was visible as the primary glare source. The remaining windows were set in a way to keep the overall color rendering in the space as neutral as possible. The results show that macular pigment density does not influence discomfort glare perception from the sun disc filtered by color-neutral glazing in the near-peripheral field of view. However, when exposed to the sun disc filtered by saturated blue-colored glazing also in the near-peripheral field, participants with higher macular pigment density were better able to tolerate the glare, indicating a significant influence of macular pigment in this case. In regards to the influence of color, results show that the perceived color of the sun disc (as filtered by colored glazing) has a strong influence on participants' perception of glare. Direct sunlight filtered through four types of colored glazing of a similar visible (photopic) transmittance caused significantly different levels of discomfort glare perception amongst the participants. More precisely, participants experienced statistically higher levels of glare under the red and blue glazing compared to the colorneutral or green glazing. The findings show that the photopic luminosity function (V2°(l)) is not an appropriate weighting function to characterize the spectral sensitivity of the human eye when a high-intensity colored glare source is in

Le quartier du Vallon à Lausanne est très énigmatique. Malgré leur situation au cœur de la ville, ses infrastructures de réintégration sociale et leur position topographique en cuvette en font un lieu marginalisé et souvent vu comme inhospitalier. Cependant, les dynamiques sociales et culturelles qui s’y sont instaurées en font un exemple particulièrement inspirant de communauté participative, autogérée et vivante. Depuis 2016, le Vallon s’ouvre au reste de la ville en organisant des festivals qui se déroulent en son sein, en promouvant la culture, l’art ainsi que leur mode de vie et valeurs. Malheureusement, cette énergie et cette vie participative manquent de visibilité aux yeux du grand public. Dans ce projet, nous proposons une réinvention et une mise en valeur des espaces collectifs que nous avons identifiés. Par une dilatation de la rue, une collision se fait entre les lieux communautaires et le domaine public, créant de nouveaux espaces à usages multiples. Ils sont délimités et marqués visuellement par nos interventions architecturales basées sur l’identité quelque peu chaotique et festive du quartier. Dans ces lignes, ces interventions prennent temporellement la forme d’un grand festival dans lequel la ville est invitée pour y rencontrer différents acteurs de cette entité très hétérogène. Par leur structure scénographique, les configurations éphémères et changeantes ainsi créées permettent de répondre aux multiples atmosphères dont le festival a besoin.

This research paper aims to simplify the question of how to take human movement into account when assessing the lighting conditions of a space. For a person working at a desk throughout the day doing paper-based or screen-based tasks, if it is assumed that they tend to look primarily in the direction of their work plane, does simulating a single viewpoint differ significantly from simulating three or five viewpoints? If so, under what conditions do the number of viewpoints matter to the accuracy of the simulation? A hypothesis is proposed that factors that increase the proportion of diffuse light to direct light in the view plane will decrease the importance of number of viewpoints. For example, a north-facing office will primarily receive reflected light through its windows, so simulating multiple viewpoints will not noticeably improve an assessment of the circadian potential of the space. This information could both help those trying to determine the healthy lighting potential of an unbuilt office and those trying to design real-life experiments to assess the lighting in an extant space.

Lausanne, été 2048. Il fait chaud. Son climat s’apparente à celui des Balkans. L’image de la ville idyllique, entre lac et montagnes, s’estompe face à un quotidien rythmé par une course contre la chaleur. Les îlots de fraîcheur forment le nouveau paysage urbain que la densification – acte nécessaire et durable – reconfigure aussi. Avec son parc et ses logements, l’îlot situé dans le quartier de Sébeillon devient, dans le cadre de ce projet, un lieu de vie continuellement animé, vivant et fonctionnel, caractérisé par sa mixité sociale et des programmes qui se superposent et s’entremêlent. Habiter en coopérative, c’est faire preuve de sens de la durabilité. L’expérience d’un mode de vie nouveau est au centre de la conception même du bâtiment qui est reconnecté à la communauté et à l’environnement. Le projet ne prévoit aucun moyen de ventilation mécanique ou de conditionnement d’air, il part du constat que la température n’a pas besoin d’être la même dans toutes les pièces. Des zones thermiques se dessinent alors et sont traversées par un mur épais qui vient réguler, tel un organe vital, tous les besoins en flux du bâtiment. Dans un contexte climatique incertain, le projet repose sur des principes thermodynamiques connus destinés à protéger de la chaleur et à ventiler. Les différentes enveloppes s’ouvrent et se ferment dans un mouvement respiratoire perpétuel, au rythme du soleil et des saisons. Ce bâtiment devient ainsi une réelle unité d’habitation bioclimatique.

Daylight is a valuable resource for both energy and human health. However, this resource is often underutilized in buildings due to the difficulty of controlling the changing qualities of daylight. Deep-plan building spaces pose an especially challenging problem because traditional sidelighting strategies are only effective for workplanes adjacent to the facade. Infrequently adjusted shading systems can also limit the availability of daylight. A number of advanced daylighting systems have been developed that attempt to address these challenges with varying priorities and success. This thesis proposes a new technology named the Soralux Daylighting System. The system is passive, requires no shading adjustments, even under direct sunlight, and works well with deep-plan spaces on the order of 8 to 15 m deep. The Soralux system presents itself as a double-glazing window unit, allowing it to be easily integrated into curtain wall facades typical of deep-plan offices in large cities. Computer simulations using the ray tracing programs Radiance and TracePro were conducted to estimate the annual performance of the system. Variables such as facade orientation, sky obstruction, and climate were evaluated for their effect on system performance. The system was found to increase light levels by a factor of 2 to 10 compared to an unshaded window at depths between 8 and 15 m from the facade. Two physical mockups of the Soralux system were fabricated for testing. The first mockup tested was a small proof-of-concept prototype, while the second was a full-scale mockup which was installed in a Tokyo office building. The physical mockups were used to evaluate visual comfort and appearance. A monitoring campaign was also conducted for the Tokyo mockup and the measured data were compared with a Radiance model of the building space to validate the accuracy of the simulation results. The average error between simulated and measured illuminance values was 16%. Based on these results, recommendations are provided identifying which scenarios are well-suited for the system. The Soralux Daylighting System is scheduled to be permanently installed into a Tokyo office building in 2012.

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.