LIPID publications

PhD theses


Daylight and temperature in buildings: interaction effects on human responses

G. Chinazzo / M. Andersen; J. Wienold (Dir.)

Lausanne, EPFL, 2019. p. 356.

DOI : 10.5075/epfl-thesis-9342.

Over the past years, increasing efforts have been devoted to understand how people perceive the indoor environment with the goal to improve building design and operation. Studies have separately addressed the effects of the four main aspects that influence the perception of the indoor environment, i.e., visual appearance, thermal condition, acoustic ambiance, and air quality. However, building occupants are simultaneously exposed to multiple indoor stimuli and their perception of the indoor environment depends on the mutual combination and interaction of such stimuli. Despite the increasing interest in the topic, few studies on the interactions between indoor factors are available. Most of them have focused on interactions between thermal and visual factors due to their large implications for energy consumption and building design. In this context, electric lighting has been primarily used as visual stimulus, leaving a knowledge gap on interaction effects in daylit environments. To address this challenge, this doctoral thesis focuses on the effects of visual and thermal interactions on human responses, with the use of daylight as the sole source of light. Two types of visual-thermal combinations are investigated: temperature and "daylight color" (i.e., daylight transmitted through colored glazing) and temperature and daylight quantity (i.e., illuminance levels). The aim of this work is threefold: (i) understand the effect of daylight color and quantity on thermal perceptual and physiological responses; (ii) investigate the influence of indoor temperature on visual perception of daylight; and (iii) explore the effect of daylight and temperature combination on the overall comfort perception. To address the previous aspects, four experiments were conducted. Two of them were carried out in an office-like test room to investigate both visual-thermal combinations. One field study was performed to further explore temperature and daylight quantity interactions. One experiment was conducted in a test room with the use of virtual reality to further investigate temperature and "daylight color" interactions. The results of this thesis show that daylight and temperature do interact, influencing human responses in a perceptual rather than in a physiological way. The interaction effects are bi-directional, as temperature influences visual perception, and daylight color and quantity affects thermal perception. Daylight conditions and indoor temperatures simultaneously and equally contribute to the overall comfort perception, but only after a relatively long exposure to the visual stimulus. The findings of this research suggest that indoor factors should not be considered separately but in combination. The integration in both research and practice of interaction effects between indoor factors will ultimately contribute to the improvement of comfort conditions inside buildings. Potentially, this integration will also allow to reduce the energy consumed in buildings to guarantee occupants' comfort due to the extension of the comfort ranges that currently neglect interaction effects between indoor environmental factors. Disentangling for the first time the complex relationship between daylight and indoor temperature, this research constitutes an additional step towards understanding interactions of indoor factors and contributes to the establishment of a comfortable and energy-efficient built environment.

Urban planning support based on the photovoltaic potential of buildings: a multi-scenario ranking system

G. Peronato / M. Andersen; E. Rey (Dir.)

Lausanne, EPFL, 2019. p. 289.

DOI : 10.5075/epfl-thesis-9051.

An increased use of renewable energy and of energy efficiency measures in buildings is needed to face the urgency of climate change. Buildings are in fact among the highest worldwide consumers of primary energy, mostly of fossil fuel origin, while still making insufficient use of in-situ renewable energy sources. To find a solution to this situation, many municipalities have promoted the use of solar cadastres mapping the solar energy potential of the existing building stock. However, their implementation has limits from different points of view including assessment accuracy, representation methods, and decision-support. To overcome these limits, this thesis proposes a planning-support system based on the photovoltaic (PV) potential of buildings. The goal is to provide decision-makers and stakeholders with a robust method to assess the potential of photovoltaic electricity generation of existing buildings under uncertain environmental conditions. The developed methodology is based on an urban-scale modeling workflow that includes the simulation of the photovoltaic electricity production and a simplified estimation of the building energy retrofit potential. Existing state-of-the-art models for solar radiation, building energy and PV performance are coupled in the workflow, which relies on a vector 3D city model featuring an accurate representation of buildings, terrain, and vegetation. The proposed modeling workflow also includes an innovative approach for simulating the arrangement of PV modules on the building envelope, which influences both the energy yield and the acceptability of the system. The modeling workflow is in turn integrated into a planning-support system that provides a robust assessment of the photovoltaic potential through risk-averse scenarios. We consider here two crucial yet underestimated uncertainty factors: weather and vegetation. The results are aggregated at different scales and, for each scale, the spatial locations are ranked through pairwise comparisons according to relevant energy indicators. The results are finally displayed in a 3D-mapping tool featuring false-color overlays at the considered aggregation scales to address different objectives and inform decision-makers. We conducted sensitivity analyses towards different input data resolutions and modeling scenarios so as to achieve a good trade-off between accuracy and computational cost and define confidence intervals for the calculated values. The simulated PV yield was also compared against measured data from an existing PV installation. The proposed modeling workflow and planning-support system were tested in an urban district within the city of Neuchâtel (Switzerland). The analysis highlighted areas with the highest potential and provided a priority list of interventions. It also showed the impact of vegetation on absolute results and especially on the ranking of the spatial locations evaluated by their energy potential.


Perceptual Dynamics of Daylight in Architecture

S. F. Rockcastle / M. Andersen (Dir.)

Lausanne, EPFL, 2017. p. 275.

DOI : 10.5075/epfl-thesis-7677.

In our experience of daylit architecture, our visual perception is greatly impacted by the ephemeral and inherently dynamic conditions of the surrounding environment. Driven by changes in sky type, time-of-day, and time-of-year, these variable conditions can alter our impressions and appraisal of indoor space. Daylight, including both direct sunlight and indirect skylight, drives a powerful range of perceptual phenomena, which transform structured geometry into a time lapse of slow and smooth or fast and harsh effects. Between the disciplines of architectural design and building engineering, there are many approaches to evaluating daylight performance, from qualitative considerations such as texture, color, composition, and ambiance to compliancy targets regarding task performance, energy, and visual discomfort. While some of these considerations, like visual discomfort, are both quantitative in prediction method and qualitative in subjective evaluation, there are few quantitative measurements developed to predict the positive perceptual impacts of light on human perception. Unlike other environmental factors like temperature, air quality, and sound, daylight creates direct impacts on the appearance of a space and cannot be divorced from the simultaneously aesthetic implications it has on architectural design. Research in daylight is therefore necessarily interdisciplinary, as it integrates physics, with the psychology of emotion, the bio-mechanics of perception, and the aesthetics of architectural design. To integrate perceptual, aesthetic, and emotional considerations into lighting performance evaluation, the aim of this thesis is to determine whether objective, quantifiable characteristics of luminous composition within an architectural scene can be linked to subjective evaluations of visual interest (like contrast, excitement, pleasantness, etc.) and whether these characteristics are sensitive to temporal dynamics. This thesis will begin with a review of existing quantitative measures for predicting contrast perception in daylit scenes (both real and digital) and will present a comparison of these measures using a catalogue of rendered scenes. Through a pair of experiments designed to induce visual effects and record subjective responses - an online survey using 2D renderings and an immersive 3D study done in Virtual Reality - this thesis will introduce a method for predicting those perceptual responses using image-based algorithms and a proportional odds model. Using the algorithms and model developed from experimental data, a visually immersive, simulation-based approach will be adopted to evaluate attributes of visual interest through space and over time. By selecting a series of architectural spaces to exemplify this approach, dynamic predictions of daylight-induced excitement across an array of eye-level view positions will show the highly variable nature of perceptual performance and its capacity to impact occupant appraisals of space. The novelty of the proposed measures, prediction model, and simulation-based approach opens an exciting new frontier in daylight performance evaluation, demonstrating the importance of occupant perception alongside existing task, energy, and comfort considerations.


Light-driven model for identifying indicators of non-visual health potential in the built environment

M. L. Ámundadóttir / M. Andersen; S. W. Lockley (Dir.)

Lausanne, EPFL, 2016. p. 302.

DOI : 10.5075/epfl-thesis-7146.

This thesis introduces a new approach to characterize and evaluate ocular light exposure based on the discovery of novel blue light-sensitive photoreceptors in the human eye. These photoreceptors are the primary mediators of 'non-visual' responses impacting human health, from resetting the circadian clock to directly alerting the brain. In recent years, studies have found that light at short-wavelengths is more effective than light at longer wavelengths at inducing and suppressing a range of 'non-visual' responses. Although it has been recommended that we approximate the spectral sensitivity of these novel photoreceptors with an action spectra peaking near 490 nm, the optimal approach for quantifying non-visual spectral effectiveness is yet unknown. These novel photoreceptors, in addition being photoreceptors themselves, receive inputs from the classical photoreceptors (rods and cones) that in return affect the overall spectral sensitivity of the non-visual system as it changes with lighting conditions. Due to this time-varying spectral sensitivity and the relatively slow temporal processing, the relation between dynamic external light stimuli and the magnitude of non-visual responses cannot be explained with a single function or a simple threshold value. To better understand these non-linear and unknown relations, this thesis aims to develop a novel computational method, based on recent findings about the 'non-visual' - also called non-image-forming - effects of light on human health. A dynamic wavelength-dependent model framework is proposed to evaluate the non-visual health potential of light. This novel approach integrates the spectral effectiveness of irradiation and accommodates time-varying spectral sensitivity functions. These time series of light quantities serve as inputs for the light-driven model, which accounts for light intensity, duration, history, and timing of light exposure. By quantifying light in terms of spectral effectiveness and temporal dynamics, different light exposure patterns can be ranked in terms of its potential to have an impact on human health. The final objective of this thesis is to support the design of healthier buildings by applying evidence-based lighting criteria, which can then inform architectural design through a simulation-based approach. Incorporating non-visual effects into a building simulation workflow requires a good approximation of daylight spectra as it varies with sun position and sky type. Performance predictions must also account for occupant behavior and scheduling, which brings us to the question: How can we apply such a method to make informed decisions about our built environment? The integration of the proposed model into a functional simulation workflow is demonstrated using an architectural case study but first the non-visual spectral effectiveness of light will be evaluated under varying sky conditions to analyze the model output sensitivity to input accuracy. The model and its application to the built environment will then be investigated using multiple view directions and by considering occupant behavior and scheduling to make an immersive prediction within a space. This novel computational approach can be seen as a first step towards human-centric lighting application, simulating an occupant's light consumption to evaluate non-visual health potential that can support decision-making in the built environment.

On the sensitivity of buildings to climate

P. Rastogi / M. Andersen (Dir.)

Lausanne, EPFL, 2016. p. 350.

DOI : 10.5075/epfl-thesis-6881.

Building simulation requires a large number of uncertain inputs and parameters. These include quantities that may be known with reasonable confidence, like the thermal properties of materials and building dimensions, but also inputs whose correct values cannot be known with absolute certainty, notably weather and occupancy. A simulation run is not, strictly, a prediction. Since the parameters and calculations are approximations of real-world phenomena and materials, the exercise is essentially uncertain. Regardless of whether simulation is interpreted as a prediction or an approximation indicative of average behaviour, including explicit bounds of uncertainty is more informative for a decision-maker than a single point estimate. This thesis presents results for two related but independent proposals for sensitivity and uncertainty analyses in building simulation, particularly to weather. The first is a novel, generalisable procedure for generating synthetic weather data to carry out a Monte Carlo experiment with a building simulation model. The second is a technique for training emulators or response surfaces to rapidly obtain estimates of performance outputs from simulation models, using Gaussian Process regression on small training data sets. The two parts, together and separately, enable the quantification of the lack of knowledge about an input, and the impact of this uncertainty on the final results. The synthetic weather time series developed are an ensemble of realistic hourly data whose mean statistical characteristics are close to the typical year used to generate them. The procedures developed are generalisable with minimal expert input. We avoid presenting a unified model for all climates, leaving some tuning parameters like the extent of correlation, and the unknown coefficients of stationary time series models, to be calculated empirically (based on the typical file of a given climate). The emulators are created using regression, comparing the performance of classical parametric regression with a non-linear technique based on Gaussian random processes. Our proposal trains reliable models on small samples, reducing the computational burden, and gives an explicit estimate of the uncertainty for a prediction, since the response at any sampled point is modelled as a Normally-distributed random process. Once again, we avoid a unified emulator or regression model because the response from one building (defined by its geometry and usage in this case) is not necessarily an appropriate description of the response of another. This work is a step towards practical tools for the use of building simulation in a stochastic paradigm. Both elements of the thesis contribute toward explicitly estimating the uncertainty in the results of building simulation, using empirical or data-driven techniques. The types of the time series and emulator models are general enough to work on any climate or building, with parameters obtained from the simulated/typical sample at hand, but the importance of different aspects and the nature of a building’s response are determined uniquely (i.e., parameter values). The work is easily extensible to the analysis of the sensitivity of a building, or groups of buildings, to any inputs. The concepts proposed in this thesis may also be used for stochastic optimisation and models to predict performance metrics other than the annual sum of energy.

Solar potential in early neighborhood design

É. Nault / M. Andersen; E. Rey (Dir.)

Lausanne, EPFL, 2016. p. 308.

DOI : 10.5075/epfl-thesis-7058.

In light of the acknowledged need for a transition toward sustainable cities, neighborhoods and buildings, urban planners, architects and engineers have to comply with evermore demanding energy regulations. These decision-makers must be supported early-on in their process by adequate methods and tools. Indeed, early-design decisions, which concern parameters linked to the building form and urban layout, strongly dictate the solar exposure levels of buildings, in turn influencing their energy need (e.g. for heating and cooling) and production potential (e.g. through on-site active solar systems). Despite the spread of existing digital tools, limitations remain, withholding their integration into the early design process. These considerations lay down the context within which this doctoral research was carried out. The main objective of this thesis is the development of a performance-based workflow to support decision-making in early-design neighborhood projects. The performance is here defined through three criteria: (i) the daylight potential, quantified by the spatial daylight autonomy, (ii) the passive solar potential, quantified by the annual energy need for space heating and cooling, and (iii) the active solar potential, quantified by the annual energy production. The research process consisted of two main phases. First, the development of a performance assessment engine allowing real-time evaluation of an ensemble of buildings. Second, the integration of this method into a decision-support workflow, taking the form of a digital prototype that was tested among practitioners. For the first phase, a metamodeling approach was adopted to circumvent the limitations associated to simulations involving solving physics-based equations. Mathematical functions were obtained to predict the daylight and energy performance of a neighborhood, from a series of geometry- and irradiation-based parameters, easily computable at the early-design phase. To derive these functions (or metamodels), a neighborhood modeling and simulation procedure was executed to acquire a dataset of reference cases, from which the metamodels were trained and tested. The resulting multiple-linear regression functions, combined to an algorithm for quantifying the active solar potential from the irradiation data, formed our performance assessment engine. To assess its usability and relevance, the workflow was implemented as a prototype, supported by existing 3D modeling and scripting tools. Inspired by the emerging performance-driven and non-linear design paradigms, a multi-variant approach was adopted for this implementation; from the space of possible designs defined by a small set of user-inputs, a series of neighborhood variants are generated through a random sampling algorithm. Results of their evaluation by the core engine are displayed to allow a comparative assessment of the variants in terms of their morphology and solar potential. Having been tested among practitioners during workshops, the prototype appears promising for providing design decision-support. Direct feedback gathered from participants support the relevance of the approach and reveals multiple avenues for further improvement. Results collected during the workshops also allowed probing the validity boundaries of the metamodels: the prediction accuracy achieved attests the potential of the approach as an alternative to more complex methods, less adequate for exploring early-phase design alternatives.



Human responsive daylighting in offices

M. Sarey Khanie / M. Andersen; J. Wienold (Dir.)

Lausanne, EPFL, 2015.

DOI : 10.5075/epfl-thesis-6660.

This dissertation proposes a novel gaze-driven approach for dynamic discomfort glare assessments as a first step towards understanding human responsive comfort with respect to daylight. The objective was to observe the natural gaze behaviour in relation to glare for office spaces with the conditions implicitly constrained by real world luminous conditions. In the existing visual comfort models human behaviour is not sufficiently considered. These models employ only subjective assessments, which lack an objective understanding of the factors affecting the perceptual mechanism of light-induced visual discomfort. They so far have not integrated the inter-dependencies of visual discomfort perception and human gaze responses and have been limited to a fixed-gaze assumption directed towards the office task area. In this dissertation, a gaze-driven approach is developed and adopted in the discomfort glare assessments. The assessments were done in a series of experiments in simulated office setting under different lighting conditions where participants’ gaze responses with means of mobile eye-tracking as well as their subjective assessments were recorded while monitoring photometric quantities relevant to visual comfort using high dynamic range luminance imaging. Integration of the luminance images coupled with eye tracking enabled us to obtain the gaze-centred luminance fields, which gives a better estimate of actual luminance values perceived by the eye, used as a basis to investigate the gaze direction dependencies of visual comfort. This PhD dissertation describes different stages of conception of this novel dynamic discomfort glare assessment method. In the experimental phase, two pilot studies were made for proper integration of the adopted methods and techniques into discomfort glare assessments. Development of several routines, algorithms and tools to identify and translate the gaze directions in order to derive the actual luminance field perceived by the participants were needed to achieve this goal. A final comprehensive experimental phase was realised to investigate gaze behaviour in response to light. As a first validation step, the gaze-driven approach was compared to the fixed-gaze approach. Then the effects of different luminance levels as well as different view outside the window on the dynamic shifts of the gaze were investigated.The developed approach demonstrates the need to integrate gaze direction patterns into visual comfort assessments, which move us beyond the existing assumption of a fixed-gaze direction towards a gaze responsive comfort.



Influence of control patterns for lighting and shading systems on the predicted energy performance of buildings

P. Correia da Silva / V. Leal; M. Andersen (Dir.)

Faculty of Engineering, University of Porto, Portugal, 2012.

Windows are one of the most complex determinants of the office indoor environment and have a significant impact on the overall energy demand for electric lighting, heating and cooling, which typically account for more than 50% and often more than 70% of the final energy demand of office buildings. Building occupants tend to adjust the lighting and shading devices dynamically, as a function of the indoor and outdoor environmental conditions and of the way how these conditions impact their visual comfort perception. Several control criteria to characterize this interaction have being proposed and some of those criteria are already integrated in building simulation tools. This research aimed to assess the impact of considering a given control model instead of another on predicted energy demand, and to evaluate how consistent the different behavioral models suggested in the literature and currently used in dynamic simulation are when compared with the patterns of control observed in real office environments. A comprehensive simulation case study carried out to understand the impact of the use of different control patterns on the selection of transparent façade design options revealed that these influence significantly the predicted energy performance and also the selection of design alternatives. In order to obtain some field indications of how occupants actually control their lighting and shading devices and, moreover, how the observed behaviors match the patterns published in the literature, eight single-occupant offices were monitored during two months each. Monitoring results showed that the actions of controlling the lighting state based solely on the availability of daylight are less than those associated with established schedules or routines. However, daylight availability does have an impact on the decision to turn lighting on when arriving to the office, at least when returning from long absences. It was also observed that the action of closing the shadings during occupation time are primarily connected to high values of transmitted solar radiation or direct solar radiation hitting the workplace. The results of this research indicated some implications regarding the use of buildings energy simulation softwares and the control/behavioral models that they currently include. In particular, it seems that the current algorithms to control the electric lighting should be used only in connection with daylight controls. The main needs for further developments in the control of shadings regards the inclusion of direct solar radiation as a decision variable, and a modulation according to DGI and/or DGP thresholds when opening the shadings.



An Interactive Performance-Based Expert System for Daylighting in Architectural Design

J. M. L. Gagne / M. Andersen (Dir.)

PhD in Building Technology, Department of Architecture, Massachusetts Institute of Technology, 2011.

Design practitioners are increasingly using digital tools during the design process; however, building performance simulation continues to be more commonly utilized for analysis rather than as a design aid. Additionally, while simulation tools provide the user with valuable information, they do not necessarily guide the designer towards changes which may improve performance. For designing with daylighting, it is essential that the designer consider performance during the early design stage, as this is the stage when the most critical design decisions are made, such as the overall building geometry and faqade elements. This thesis proposes an interactive, goal-based expert system for daylighting design, intended for use during the early design phase. The system gives the user the ability to input an initial model and a set of daylighting performance goals. Performance areas considered are illuminance and glare risk from daylighting. The system acts as a "virtual daylighting consultant," guiding the user towards improved performance while maintaining the integrity of the original design and of the design process itself. This thesis consists of three major parts: development of the expert system, implementation of the system including a user interface, and performance assessment. The two major components of the expert system are a daylighting-specific database, which contains information about the effects of a variety of design conditions on resultant daylighting performance, and a fuzzy rule-based decision-making logic, which is used to determine those design changes most likely to improve performance for a given design. The expert system has been implemented within Google SketchUp along with a user interface which allows a designer to fully participate in the design process. Performance assessment is done in two ways: first by comparing the effectiveness of the system to a genetic algorithm, a known optimization method, and second by evaluating the success of the user interactivity of the tool, its use within the design process, and its potential to improve the daylighting performance of early stage designs.



Innovative bidirectional video-goniophotometer for advanced fenestration systems

M. Andersen / J.-L. Scartezzini (Dir.)

Lausanne, EPFL, 2004. p. 237.

DOI : 10.5075/epfl-thesis-2941.

Efficient collection and redistribution of the direct and diffuse components of daylight in buildings remains a major objective of advanced fenestration systems. Such systems, including novel solar blinds, new glazing or coating materials and daylight-redirecting devices, can improve significantly the penetration of daylight in deep rooms to reduce electricity consumption while improving visual comfort conditions greatly; at the same time, they can lead to larger solar gains in winter combined with lower solar loads in summer. To allow their integration in buildings and benefit from their potential as energy-efficient strategies, an in-depth and accurate knowledge of their directional optical properties is necessary. These properties are described by Bidirectional Transmission (or Reflection) Distribution Functions, abbreviated BT(R)DF, that express the emerging light flux distribution for a given incident direction. Such detailed transmission or reflection functions are intended to be used by the building industry to optimize the luminous performances of innovative solutions for windows and to describe photometric properties of complex glazing and shading materials according to a common format. On the other hand, they will allow daylighting simulation tools to improve their potentialities and integrate complex fenestration systems reliably in the simulation models. Their accurate assessment requires an appropriate experimental equipment. An innovative bidirectional goniophotometer, based on digital imaging techniques, was designed and set up for that purpose: instead of scanning the emerging light flux distribution by moving a sensor from point to point, an original method was used that comprises a rotating diffusing screen on which the emerging light flux is reflected towards a digital video-camera, used as a multiple-points luminance-meter. This novel approach significantly reduces the time needed to monitor BT(R)DF data, lowering it down to a few minutes per incident direction instead of several hours for conventional assessment methods, which is a critical parameter in BT(R)DF assessment as about a hundred incident directions are usually required. At the same time, it allows the gathering of continuous transmitted (reflected) light distribution figures, only limited in resolution by the pixellisation of the digital images. Moreover, by taking advantage of the considerable luminance range reached when images are captured and superposed at different integration intervals, combined to the appreciable flexibility in the data processing offered by digital imaging-based techniques, a remarkable accuracy can be achieved when assessing BT(R)DF data. This PhD thesis explains the different conception, calibration and processing stages that were necessary to develop the bidirectional goniophotometer into a functioning, validated measurement device. Its design for combining BTDF and BRDF assessments is described, the various calibration procedures for converting the CCD camera into a reliable multiple-points luminance-meter are detailed, as well as the image and data processing phases. An in-depth validation of the performed measurements was realized based on different approaches and led to a relative error on BT(R)DF data of only 10%, allowing to confirm the high accuracy and reliability of this novel device.

Master’s Theses


Beaumont Nord, une nouvelle unité d'habitation écologique et coopérative à Fribourg

A. Mitaine


Ce projet sert de détonateur au futur renouvellement urbain du quartier Beaumont à Fribourg. Il prend place dans un îlot allongé, à la limite entre deux tissus urbains de forme et d'époque très différentes: au Sud, des grandes tours de logement des années 1960, au Nord, une colline occupée par des maisons individuelles construites antérieurement. L'îlot étant vieillissant, peu attractif et pauvre en aménagement extérieur de qualité, mon projet va donc chercher à lui donner un nouveau souffle en s'inscrivant dans une réflexion fondée sur trois piliers. Le premier pilier est celui du vivre-ensemble au travers du fonctionnement d'une coopérative d'habitation et d'une mixité programmatique. Le projet est en effet composé, à part égale, de locaux commerciaux, de logements traversants de haute qualité et de locaux coopératifs tournés vers une rue centrale Est-Ouest catalysant les activités. Le second pilier est celui de l'écologie, notamment par une bonne gestion de l'eau, par l'utilisation des principes de l'architecture bioclimatique et par l'emploi du bois et de la terre stabilisée comme matériaux de construction. Le troisième et dernier pilier est celui de l'architecture qui devrait faire se rejoindre les deux précédents autour d'une composition vraiment qualitative et singulière. Les circulations et la place au centre du projet permettent de lier l'ensemble des programmes publics et semi-publics en les faisant remonter dans les étages jusqu'aux toitures.



“AtlemAgora”: interface sportive entre la ville de Genève et son extension

C. Hegelbach; N. Roiron


Le sport et la ville entretiennent une relation complexe. Le tissu dense des centres urbains peine à absorber les volumes généreux intrinsèquement liés aux installations sportives. Pourtant l'activité physique est inhérente à la vie des hommes depuis des milliers d'années. Dans la Grèce antique les gymnasion – gymnases – occupaient une place importante dans la cité, au point d'en être une des principales caractéristiques. Ils étaient bien entendu dédiés au sport, mais servaient aussi de lieu de sociabilisation accueillant même des débats philosophiques. Ils participaient donc activement à la vie citoyenne, au même titre que le théâtre ou l'agora. De nos jours les centres sportifs ont tendance à s'éloigner des centres urbains et de leurs habitants, perdant ainsi la relation étroite qui les liait. La cohabitation du sport et de la ville contemporaine, bien que complexe, peut se montrer favorable à de nombreux égards. Notre projet vise à réconcilier vie citadine et sport. Il s'intègre aux centres sportifs des Vernets et de la queue d'Arve, situés en bordure d'une zone industrielle. Cette dernière est vouée à disparaître au profit de l'extension du centre-ville de Genève. Ces infrastructures permettraient ainsi de lier la ville à ce nouveau quartier. La localisation et les dimensions de ces équipements offrent un terrain propice à la création d'une mixité nouvelle, favorisant l'usage par la proximité, bénéfique tant à l'échelle de la ville qu'à celle de l'individu.



Au fil du temps. Une infrastructure évolutive dans un espace vert préservé à Fribourg

J. Ruffieux


La prise de conscience des enjeux environnementaux et l'accélération continue des changements sociétaux questionnent les modalités actuelles de production du bâti. Avec le développement des technologies, notre espace est devenu de plus en plus virtuel, nous faisant perdre le lien avec notre environnement direct; nous vivons la majorité du temps à l'intérieur, que ce soit pour nous déplacer, habiter ou travailler. Pour répondre à ces enjeux, le projet Au fil du temps propose une infrastructure pérenne pour la ville de Fribourg s'inscrivant sur le site de la caserne et du parc de la Poya. Reliant les multiples composantes du site, elle vient se rattacher aux voies ferrées en bordure de site et préserve ainsi un vaste espace vert pour les générations futures. A cette épine dorsale – irriguée par des systèmes de circulation d'usagers, de techniques et de ressources – peuvent s'accrocher de manière évolutive des modules accueillant une pluralité de fonctions. Par sa situation spécifique, l'habitat proposé bénéficie d'un rapport privilégié au végétal. Le concept paysager occupe ainsi une place de choix dans la démarche et se développe sous différentes formes le long du flux de circulation mais aussi entre les multiples unités modulaires. Entre intérieur et extérieur, les limites s'estompent. En analogie avec la nature, le projet Au fil du temps possède ainsi par sa conception les principes intrinsèques lui permettant d'évoluer, de grandir et de se renouveler.


Energy scenarios in urban renewal processes: a GIS-based approach to analyse the urban-scale installation of photovoltaics. Case study of two neighborhoods in Neuchâtel

Z. Shafi Zadeh


With the “Energy Strategy 2050”, Switzerland is planning to gradually withdraw from the use of nuclear energy and consequently integrate a larger share of renewables sources. Among all types of renewable sources, photovoltaic systems are ideally suited for energy supply in urban structures. This thesis defines the potential of the roof-based photovoltaics for different energy scenarios in urban areas generated in the Geographical Information System (GIS). To evaluate this potential, the technical aspects like solar irradiation potential and available roof areas are combined with the analysis of the urban morphology. The latter consists of the urban context and system visibility analyses on the one hand and the social aspects analysis of photovoltaic installation on the other hand. The methodology is applied in two neighborhoods in the city of Neuchâtel presenting different urban morphologies. Each neighborhood has been evaluated by the help of the models defined in GIS. For each building, the models evaluate the solar energy potential, the available roof surface, the visibility level as well as the sensitivity level. Thereafter, based on these analyses two sets of energy scenarios are presented for each neighborhood. Despite the limits mainly related to the social analysis, caused by the limited number of respondents, the presented methodology can be used as a decision support tool providing the decision makers with important information about the level of photovoltaic integration based on the morphological or social aspects of the urban area. In other words, it gives the decision makers the possibility to choose the scenario definition method based on both their territory context and their needs for producing energy.



Paysages symbiotiques. Un parc multifonctionnel au service de l'agglomération yverdonnoise

J. Gattoni


«Bienvenue au parc des Avants de la Cariçaie! Venez triez vos déchets verts chez nous! Déposez-les dans nos collecteurs répartis sur le territoire et recevez en échange leur équivalent en Biocoin, notre monnaie d'échange. Ce dimanche, dégustation de gaspacho à l'yverdonnoise et balade commentée sur la flore de la Cariçaie.» ; ; Nous sommes en 2030, suivant les tendances actuelles, les rendements en énergie et électricité des usines de traitement des déchets ont considérablement augmentés. Les exploitants cherchent à attirer ceux qu'ils appellent dorénavant, des clients. Dans la plaine de l'Orbe, on se dispute les dernières communes non desservies par un méthaniseur. Yverdon, capitale régionale en mutation, espère les attirer. Au Nord des chemins de fer, le nouvel éco-quartier anime les discussions des yverdonnois. Ceux-ci, craignant une privatisation du bord de lac, sollicitent un parc pour tous. Une association d'infrastructures simples et paysagères permettent une réutilisation des résidus en biomasse. Un biodigesteur valorise les déchets collectés en biogaz et engrais. L'eau résiduelle, issue de la STEP et de l'éco-quartier, est enrichie de ces nutriments et répartie sur le parc par une suite de bassins et de canaux. L'excédent renaturalise les bords du lac, prolongeant les strates boisées et marécageuses de la Cariçaie. Jardins de maraîchages, pavillons de séchage, terrains de sports ou grill au biogaz ... chaque gramme de déchets participe au fonctionnement du parc.


Mise en scène: le théâtre et la ville

O. Allimann; E. J. M. Revaz


Depuis toujours, le théâtre est l'un des acteurs principaux de la ville. Son statut emblématique a influencé la construction de nombreux quartiers, avenues et places. Ce projet propose une nouvelle façon de bâtir un théâtre en milieu urbain. En s'implantant sur la place de la Planta au coeur de Sion, capitale valaisanne, il requalifie l'entrée de la vieille-ville. Au rez-de-chaussée, un portique dessine le front Ouest de la place historique, formant un seuil entre elle et l'avenue de la Gare. Au niveau supérieur, celui-ci devient une passerelle publique sur laquelle habitants et visiteurs peuvent contempler les deux collines représentatives de la ville. Les bâtiments publics historiques et l'arrière-plan formé par les Alpes s'ajoutent à ce décor théâtral. Office du tourisme, salle polyvalente, bar et théâtre s'accrochent à la ligne forte tracée par le portique. Le bâtiment principal, destiné à l'accueil de représentations théâtrales, est une black box en maçonnerie, soit un volume massif à l'intérieur duquel se trouve un espace modulable. Les autres parties du programme reprennent ce même langage constructif. La passerelle légère serpente entre ces différents volumes, proposant une véritable promenade panoramique aux spectateurs. Le fonctionnement de la place et du théâtre se modifie au fil des saisons et des manifestations, selon un vaste éventail d'échelles et de configurations. Le théâtre se met ainsi en scène dans la ville.



Feeling Rice: pavillon de la Chine, Milan Expo 2015

M. Deshaires


L'Italie et la Chine sont deux pays centenaires aux fortes traditions et cultures qui se rencontrent lors de l'Exposition Universelle de Milan 2015. Avec sa participation à l'Expo, la Chine présentera sa ressource naturelle et agricole principale, le “riz”, et proposera des solutions aux problèmes de la faim dans le monde, en ligne avec le thème de l'Expo, Nourrir la planète. Énergie pour la vie. Le projet consiste à créer un pavillon composé d'espaces d'expositions, transmettant la culture et les technologiques agricoles (du “riz”), dont les objectifs principaux sont d'informer, d'éduquer et également bien sûr de faire plaisir. Il illustrera la Chine des traditions culinaires ainsi que son potentiel technique et scientifique: points forts du pays. Le pavillon s'inspire d'un paysage très typique de la Chine: les rizières. L'expérience dans le Pavillon s'imprègne du jardin chinois traditionnel, sinueux et renfermé par une enceinte, tout en s'adaptant à la perception occidentale, linéaire et claire. Les visiteurs découvrent progressivement différentes atmosphères s'inspirant des couleurs et des ambiances typiques de la Chine. L'enjeu du projet est de créer un pavillon qui, tout en représentant son pays, épouse parfaitement la vision occidentale par son architecture, et d'engendrer une relation entre une balade architecturale dirigée et définie par des ambiances, et une exposition agricole.


Lutry, pôle urbain durable. Une densification sur mesure

G.-L. Ponzetta; B. Wenger


Afin de limiter leur étalement et leur consommation, les villes doivent se concentrer et de se décentraliser. Pour l'Est lausannois dispersé, cela passe par un renforcement des centralités existantes. La qualité patrimoniale et la faible marge de manœuvre des bourgs historiques exigent des solutions sur mesure pour que la transition de ces lieux en pôles urbains durables soit une chance. Pour concrétiser cette vision, le projet propose l'implantation aux abords du centre historique de Lutry d'une nouvelle pièce urbaine qui cherche à adapter le principe global du développement durable à la spécificité du lieu. Son dessin par le vide de l'espace public devient un jeu entre les références aux qualités historiques du lieu, les reconnexions spatiales et la réponse à la densité, la mixité et la perméabilité piétonne. Les thèmes de l'eau, de la biodiversité et des apports de lumière, particulièrement choisis pour ce lieu, sont une opportunité pour insérer encore plus le projet dans le site. Les volumes monolithiques ainsi sculptés reprennent les profondeurs des habitations du bourg, tout en assurant la compacité. Les espaces intérieurs s'organisent alors autour de puits de lumière et cherchent les relations aux différents espaces extérieurs. L'architecture massive garantit à la fois le confort intérieur et emphase en même temps les percements qui dessinent la façade, dont la configuration varie selon leur situation, poussant jusque dans le détail le singularisme de l'intervention.


Design of an adaptive shading system for arid climates : theoretical, numerical and experimental analyses

L. Giovannini; M. Andersen



Refurbishment of Existing Envelopes in Residential Buildings: assessing robust solutions for future climate change

G. Chinazzo


Evaluating the energy consumption of different design solutions during the design process is essential to reach energy targets. Conventionally, building energy performance is evaluated with energy simulations using a single input weather file (design or typical year) referring only to present weather conditions. Recent works, for example by Gaterell at al. for sites in the United Kingdom, suggest, however, that it is necessary to also include weather files describing climate conditions in future years. That is, the effect of predicted climate change on building performance. Buildings have a life span of 50 to 100 years and so must perform satisfactorily under both current and future climate, adjusting to take advantage of opportunities and to moderate potential damage caused by a changing climate (Wilde et al. 2008). Given the fact that climate is a singularly stochastic phenomenon and that we cannot predict the weather in future years with complete certainty, weather inputs necessarily have intrinsic uncertainties. Using a single weather file in building simulations, regardless of its source or generative algorithm, could lead to inaccurate energy consumption forecasts, and therefore wrong design decisions. In any case, the development of typical weather files was not always done keeping in mind forecasting, but rather what-if analyses. The innovation in our study consists in the introduction of more than one input weather file in building simulation to represent both present and future years. Our methodology aims to assess the robustness of different design solutions over many possible future climate projections, i.e. the sensitivity of a design or device to uncertain climatic outcomes. We focus on the robustness of refurbishment measures compared to the robustness of the non-refurbished building. We assess each intervention in terms of energy consumption. We decided to focus on existing buildings since they represent the biggest opportunity to reach energy targets today in Europe. In fact, the majority of the European building stock was constructed before any energy regulations and tends to perform poorly for energy consumption and comfort. We propose three indices to make comparisons between refurbishments. The Robustness Index (RI) compares the robustness of the each solution in terms of its range of energy usage. The Energy Saving Index (ESI) assesses the refurbished models in terms of energy usage difference in comparison with the non-refurbished model or base-case. The Gather Index (GI) summarizes the results of the two previous indices to compare the performance of the different refurbishments in terms of both robustness and energy efficiency. As a case study, we evaluated the robustness of an existing dwelling with twenty-two realistic refurbishments in Turin, Italy. The retrofit solutions focus on the thermal properties of the envelope by varying the U-value, the solar heat gains, the thermal mass and the air tightness of the envelope. The main outcome of our study is that interpreting numerical simulations of future energy consumption based on single-point estimates of input/output data (i.e. one typical weather file) is risky. Results are better treated as being probabilistic rather than deterministic, as is the norm today. Discussing outcomes in terms of ranges instead of single values improves estimates of outcomes, making it possible to identify robust design solutions for policy and investment decisions.


Light-Syntax Zones in Daylit Café Spaces: A Novel Method for Understanding Occupancy

S. J. Gochenour


This thesis proposes a novel method for understanding occupancy in public indoor spaces by creating hybrid light-syntax zones, based on both simulated illuminance data and simulated configuration data. Yearly illuminance profiles and spatial syntax characteristics such as physical connectivity and visual integration were examined to develop zones which theoretically have similar occupancy rates to one another. To support the light-syntax zone concept, a case study was performed in a student cafe on a university campus. Occupancy and exterior light conditions were observed for thirteen days. Occupancy rates were mapped to each seat within the cafe and analyzed for correlations with the light- syntax zone data. A significant difference was found in the occupancy rates between different exterior light conditions (direct light present, rapidly changing/intermediate, diffuse light present) in the test cafe. A slight negative correlation was found between occupancy rates and integration and physical connectivity values, which seems to indicate that the cafe users are seeking out the most secluded spaces. However, higher illuminance values also show a correlation with higher occupancy ratios. Given the map of the space, it is possible that these two variables are confounded. Further studies are necessary to determine the validity of light-syntax zones as a tool for predicting relative occupancy within an indoor space.


Built density, solar potential and daylighting : application of parametric studies and performance simulation tools in urban design

G. Peronato


Augmenting built density helps achieve a sustainable urban development reducing, for example, transport-related energy consumption and greenfield urbanization. Yet, in order not to undermine solar potential and daylight, an integrated design approach guaranteeing building performance in dense urban contexts is needed. This thesis shows the application of building simulation tools into a parametric 3D modeling environment so as to calculate the potential energy production from solar systems, the energy needs for space heating/cooling and some climate-based daylight metrics for several design scenarios generated by the combination of fundamental geometrical parameters. This methodology is applied to three case-studies in Switzerland presenting different densification strategies at the neighborhood scale: the urban renewal of a brownfield site in Yverdon-les-Bains and two “soft densification” interventions in Geneva, i.e. roof raising in a central area and housing infill in a suburban residential district. Each case-study has been evaluated according to common morphological and environmental indicators, showing that the urban renewal project represents a good compromise between built density and building performance objectives. Moreover, a set of optimized design scenarios has been proposed for this strategy. Although the results of this work refer to specific case studies which are not representative of all urban contexts, at a methodological level the hereby presented procedure can be used as a decision support tool in the early urban design phase also in other situations and can facilitate the choice of the most appropriate densification strategy.



Les bains de San Bernardino (Grisons, CH)

A. Hainoz; L. Keller


San Bernardino est un village typique de montagne qui doit son développement au tourisme thermal du XIXe siècle et qui, de nos jours, comme beaucoup d'autres stations similaires, a perdu de son éclat. Afin de redonner vie à cette ancienne tradition thermale et de relancer le développement de San Bernardino, nous proposons un projet de bains qui s'insère dans le village et valorise les infrastructures existantes. Dans un tel projet, il est primordial de prendre en compte les besoins de l'utilisateur ainsi que son bien-être. Cependant les usagers n'ont pas tous les mêmes exigences. Le défi du projet est donc de faire cohabiter plusieurs utilisateurs et leurs différentes attentes au sein d'un même bâtiment. Le projet prend alors la forme d'un centre de loisirs destiné à la fois aux familles et aux jeunes et intègre également une partie wellness pour la détente. Les bains s'organisent le long d'un parcours qui commence à l'échelle du village et qui se développe au niveau du bâtiment à travers de multiples ambiances définies par l'eau et la lumière. Les atouts de San Bernardino deviennent générateurs du projet: la pente naturelle se transforme en terrain construit et le bâtiment s'ouvre ainsi sur le paysage alpin et bénéficie, de par son orientation, d'un bon ensoleillement.


Hermann Baur - Sauvegarde et réaffectation de l'église Saint-Michael à Bâle

L. Kehrli


L'église catholique Saint-Michael à Bâle, construite en 1948 par Hermann Baur, est modeste, mais présente une volumétrie inhabituelle pour l'époque. S'intéressant de près à la réforme liturgique, Baur révolutionna l'architecture du culte catholique en Suisse. Plus soucieux de répondre aux besoins du peuple plutôt que de construire pour une institution, les églises de Baur respirent le calme et la paix, rendant la présence divine presque palpable et l'intérêt patrimonial indéniable. Aujourd'hui la baisse d'affluence dans les églises, l'existence d'autres lieux de culte dans la même paroisse et le manque de moyens financiers, fragilisent la raison d'être de l'église Saint-Michael. Sa reconversion est le seul moyen de redonner vie à cet ensemble, tout en sauvegardant la matière existante. L'objectif du projet est de transformer le complexe en un centre œcuménique et de recherche théologique, afin de conserver la dimension religieuse de l'existant. L'église est reconvertie en bibliothèque et le programme est complété par des espaces de travail, une salle polyvalente et une chapelle œcuménique. Les environs de l'église ayant subit passablement de changements au fil des années, la difficulté consiste à réintroduire une harmonie entre l'église et ses bâtiments annexes. La redéfinition de l'espace central, initialement prévu par Baur, permet non seulement de revaloriser les abords, mais aussi d'établir une cohésion entre le nouveau et l'existant, formant ainsi un ensemble équilibré.


Habitat bioclimatique alpin

D. P. Müller


Ces dernières décennies, l'économie des régions alpines en Suisse a très largement profité d'un boom immobilier lié principalement aux résidences secondaires. Ce modèle est aujourd'hui remis en question, ce qui risque bien d'amener la plupart des régions alpines dans une phase de décroissance économique qui vraisemblablement engendrerait une migration massive des populations locales vers les villes. Une autre solution passerait non pas par une baisse de la population alpine mais par une baisse du revenu par habitant, auquel cas il est nécessaire de trouver des solutions pour vivre aussi bien avec moins. L'architecte a ici un rôle important à jouer: en concevant des logements extrêmement économes en énergie et bien plus accessibles financièrement que le chalet traditionnel, ainsi qu'en offrant des espaces collectifs et d'échange de qualité, il incite la population à vivre localement, sobrement, à se contenter de l'essentiel et à profiter de larges temps libres pour pratiquer des loisirs non commerciaux et participer à une vie villageoise retrouvée. Ce projet dispose les logements en strates étagées dans la pente. Grâce à l'utilisation optimale des gains solaires, à leur compacité et à leur excellente isolation thermique, ces derniers sont autonomes du point de vue énergétique. Par ailleurs, la densité du quartier est comparable à celle qu'on aurait obtenu avec des “jumbo-chalets”, avec toutefois l'avantage pour chaque logement de disposer d'un jardin privatif.



Light Design Driver

M. Niqui


La lumière, le vent, le flux urbain et les autres forces de l'environnement nous informent des spécificités de l'espace. Ces forces ne touchent pas seulement la conception au niveau de détail, elles peuvent être une base pour le concept de l'organisation spatiale. Ce projet propose un Light Landscape sur la base des données annuelles du rayonnement solaire qui existe dans l'espace. Ces données sont traitées comme générateur de conception et hiérarchisent l'organisation d'un bâtiment. Un Light Landscape est une enveloppe qui est informée à chaque point par la quantité de rayonnement annuel à ce point. Cette mesure définit l'orientation et l'exposition à la lumière. L'enveloppe résultant diversifie l'espace en définissant des zones d'éclairage. Elle introduit également le principe de la circulation. Dans l'étude de cas, l'effet de la lumière sur les promenades urbaines a été étudié, montrant qu'un tissu urbain définit un zonage lumière unique qui affecte le comportement des utilisateurs dans l'espace urbain. Cette influence est remarquable sur les changements de parcours et la durée des promenades. Cette étude a permis de développer la notion de champ de rayonnement qui est le lien entre les zones de lumière et le Light Landscape: un champ de force calculé d'après les données solaires. La superposition des variations de la lumière du soleil sur un tissu urbain dans un champ de force unique et constant devient un outil pour informer un paysage basé sur la lumière.


L'architecture souterraine au service de la densification

J. Tacchini


Dans l'optique de restructurer les agglomérations, les principes de densité et mixité ont depuis plusieurs années remplacé ceux d'étalement et de zonage. Accompagnée de valeurs positives comme la réhabilitation de la qualité du vivre en ville, la transformation des villes n'en passe pas moins par la résolution d'une crise spatiale; notamment en cherchant de nouveaux territoires. L'exploitation du sous-sol urbain, en tant que ressource spatiale supplémentaire, est en ce sens de plus en plus envisagée. L'objectif est d'étendre la ville vers sa composante –Z par l'établissement de fonctions dans le sous-sol en vue d'augmenter le potentiel de développement qualitatif et quantitatif d'un lieu donné. Par ailleurs, en l'absence de principes de planification, les réseaux de transport enterrés sont considérés, par hypothèse, comme les vecteurs de ce développement; les nœuds de transfert modal étant les polarités autour desquelles nous souhaitons développer nos agglomérations. Enfin, fréquentés quotidiennement, les souterrains seront à l'avenir des espaces vécus dont les attentes en termes de qualité architecturale seront égales à celles rencontrées en surface, dont l'intelligibilité est assurée aux usagers. Le site lausannois de la Blécherette offre l'opportunité d'investiguer les possibilités de penser un projet par sa dimension souterraine. Le lieu est voué à de grandes transformations directement dépendantes de la construction du métro m3. Son terminus sera ainsi l'élément essentiel de la future porte d'entrée Nord-Ouest de la ville. Le projet questionne la transposition de ce pôle public en sous-sol. Autour de l'interface métro/P+R, il propose des activités commerciales accompagnant les pendulaires et une salle de concert afin d'animer plus intensément le lieu.


Integrative approach to assess the performance of light-interacting façades and building materials

T. Moisan


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.


Comprehensive Performance Metrics for Complex Fenestration Systems Using a Relative Approach

S. Dave


Buildings account for over 40% of the energy consumption in the United States, nearly 40% of which is attributed to lighting. The selection of a fenestration system for a building is a critical decision as it offsets electric lighting use as well as impacts energy performance through heating and cooling systems. Further, the fenestration system contributes to both occupant comfort and ambiance of the space. Complex Fenestration Systems (CFS) address these factors with a variety of innovative technologies but the language to describe, discuss, and compare them does not exist. Existing traditional metrics for fenestration systems are unable to reveal the benefits that characterize complex fenestration systems because they are rigid, do not reflect annual performance, and were developed for a different purpose. The framework presented in this research offers a solution to this problem by using an annual climate-based methodology to provide a comprehensive evaluation of a system by incorporating three of the most relevant performance aspects: energy efficiency, occupant visual comfort, and ability to view through. Three metrics, the Relative Energy Impact (REI), the Extent of Comfortable Daylight (ECD), and the View Through Potential (VTP), were derived from these three criteria to express, in relative terms, a façade’s contribution to building energy use, comfortable daylight conditions, and the degree of transparency, respectively. Several practical matters were considered when developing a policy-relevant set of metrics, including both ease of calculation for manufacturers and usability for consumers. As such, the calculation methodology evolved from its initial proposal into a simplified approach, analytical where possible, and into a label-like concept for visual representation. These metrics are intended to exist as a mechanism by which manufacturers can evaluate and compare façade systems, provide high-level intuition of relative performance for designers and contractors, and enable the balance of performance objectives based on user preference. Ultimately, the creation of this comprehensive language is intended to stimulate innovation in fenestration systems and encourage their use in both new and retrofit building applications.



Daylight Variability and Contrast-Driven Architectural Effect

S. Rockcastle


Natural light is a dynamic and ephemeral tool for expressing the quality of architecturalspace. As a compliment to more traditional avenues of daylighting research that assess performance in terms of quantitative illuminance goals and glare-based discomfort, my thesis defines light variability and contrast as a finely tuned architectural effect. Under the rapidly growing context of energy conscious research, my thesis attempts to re-balance our definition of “performance” to include those perceptual and aesthetic aspects of light that are often disregarded by the world of simulation. Contrast is important to the definition of space and it is essential in understanding how architecture is enhanced and transformed over time by the dynamic and variable characteristics of daylight. Through an analysis of contemporary architecture from around the world, this thesis has developed a new typological language that categorizes architectural space in terms of contrast and temporal variation. Using this system of categorization, my thesis proposes three new metrics for the quantification of contrast and light variability to provide a more holistic analysis of daylight performance.


The Soralux Daylighting System: Passive Solar Illumination for Deep-Plan Building Spaces

K. W. Thuot


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.



Dispositif de mesure de la distribution de luminance du ciel basé sur des techniques d’imagerie numérique: développement et validation expérimentale

M. Andersen-Thys


Dans ce projet, on cherchera à calibrer un nouveau modèle d’urano-tomographe, - dit sky-scanner -, dont le principe essentiel repose sur l’utilisation d’un miroir sphérique sur lequel l’image de la voûte céleste est projetée, de manière à en obtenir une projection fish-eye. Cette projection est mise en image par une caméra CCD placée au-dessus du miroir, et dont le raccord à un ordinateur permet un traitement approprié de l’image ainsi qu’un pilotage automatisé des différents composants de la caméra vidéo. La relation entre les niveaux de gris des pixels de la caméra et les luminances qui leur sont associées permet de faire de ce système un luminance-mètre vidéo. Il s’agira donc plus précisément d’effectuer les calibrations géométrique, d’uniformité de la réponse, spectrale et photométrique de ce sky-scanner, ainsi que d’optimiser les procédures d’acquisition et de traitement des images. La distribution des luminances de la voûte céleste sera déterminée de manière quasi-continue, avec une valeur en chaque pixel. Pour permettre une validation sous le simulateur de lumière diffuse, nous adapterons la procédure de traitement des images à une discrétisation du ciel en 145 zones circulaires.

Other theses supervised by M. Andersen (MIT, 2004-2010)


Witness to the Light – The Evolution of Church Sanctuary Design & Standards of Comfort in the Last Century in Harrison County, Iowa

S. Gochenour.

BSAD thesis, Department of Architecture, May 2010

Time-Varied Daylighting Performance to Enable a Goal-Driven Design Process

S. Kleindienst.

PhD thesis in Building Technology, Department of Architecture, February 2010


Measuring Photometric and Spectral Radiometric Bi-directional Transmission and Reflection in a Video-goniospectrometer

E. Stokes.

S.M. thesis, Department of Mechanical Engineering, MIT, June 2008

Space, Light, and Time: Prospective Analysis of Circadian Illumination for Health-Based Daylighting with Applications to Healthcare Architecture

C. Pechacek.

SMArchS thesis in Building Technology, Department of Architecture, MIT, June 2008. (awarded the SMArchS 2008 Prize)

A New Approach in Data Visualization to Integrate Time and Space Variability of Daylighting in the Design Process

L. Yi.

SMArchS thesis in Computation, Department of Architecture, MIT, June 2008

Database of Light-Interacting Materials, Systems and Technologies

R. Urbano Gutiérrez.

MDesS thesis, Graduate School of Design, Harvard University, February 2008

A Battery Powered Near Infrared (NIR) Camera for the MIT HelioDome

K. Molina.

S.B. thesis, Department of Mechanical Engineering, MIT, June 2008

Development of Computer Controls for a Goniophotometer

J. Burgos.

S.B. thesis, Department of Mechanical Engineering, MIT, June 2008


New Methods for Measuring Spectral, Bi-directional Transmission and Reflection using Digital Cameras

N. Gayeski.

S.M. thesis in Building Technology, Department of Architecture, MIT, June 2007

Development of Two Heliodons at MIT and Recommendations for their Use

R. Osser.

S.M. thesis in Building Technology, Department of Architecture, MIT, June 2007

Device for Selecting Lightwave Ranges via Computer Control for Studying Building Material Properties via Goniophotometer

T. Koch.

S. B. thesis, Department of Mechanical Engneering, MIT, June 2007


Improving Daylighting in Existing Buildings: Characterizing the effect of anidolic systems

S. Kleindienst.

S.M. thesis in Building Technology, Department of Architecture, MIT, June 2006

Illumination and detection system for light-redirecting materials investigation and scale model simulations

C. Browne.

S. M. thesis, Department of Mechanical Engneering, MIT, June 2006

Considering daylight in facade renewal: The effect of new measures for daylight in the consideration of aging modern-era facade types

E. Rice.

SMArchS thesis in Building Technology, Department of Architecture, MIT, June 2006. (awarded the Ralph Adams Cram Award)


Automated Support for Experimental Approaches in Daylighting Performances Assessment

D. Ljubicic.

S. B. thesis, Department of Mechanical Engneering, MIT, October 2005

A System for Optimizing Interior Daylight Distribution Using Reflective Venetian Blinds with Independent Blind Angle Control

M. McGuire.

S.M. thesis in Building Technology, Department of Architecture, MIT, June 2005