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The goal of this research is to produce a realistic occupancy forecast as well as an ideal occupancy-based controller for increasing the performance of Heating Ventilation and Air-Conditioning [HVAC] systems. Reliable occupancy prediction is a critical enabler for demand-based HVAC control since it ensures that the HVAC system is not running unnecessarily while a room or zone is empty. We present simple yet successful occupancy prediction methods, as well as an approach for automatically setting temperature set-points, in this work. We present three alternative occupancy prediction algorithms based on historical occupancy measurements. The proposed approach uses historical occupancy profile and environmental room data to establish an occupancy identity strategy that can provide a stochastic model based on uncertain basis functions as an alternative. According to the findings, the proposed occupancy prediction algorithms could reach an accuracy of approximately 85% reliable prediction with few negative predictions.

Die Erschöpfung der Naturressourcen in Kombination mit der Klimakrise und der globalen Erderwärmung sind unter den zentralen Faktoren, die die nachhaltige Entwicklung und Energieeffizienz in fast allen Bereichen des Lebens notwendig gemacht haben. Da das Bauwesen zu den größten Umweltverschmutzer heutzutage zählt, ist die Untersuchung und Erforschung von alternativen Baupraktiken als diese, die aktuell eingesetzt werden, von wesentlicher Bedeutung. Die historischen Gebäude in Plovdiv, Bulgarien repräsentieren einheimischen Gebäuden in traditionellem Baustil aus der Zeit der Wiederbelebung Bulgariens. Sie haben den Test der Zeit überstanden. Zudem haben viele davon die Integrität und die Vollständigkeit wie vor Jahrzehnten bewahrt. In den letzten Jahren hat das zur Steigerung des Interesses seitens der architektonischen Gemeinde geführt. Sie werden als eine der Quellen nachhaltiger Architektur angesehen – entworfen und konstruiert mit lokalen und natürlichen Materialien und im Hinblick auf den Umweltkontext. Der Schwerpunkt dieser Forschung liegt auf dem Wärmeverhalten und der optischen Performance von fünf bulgarischen Volksbauten in traditionellem Baustil aus der Zeit der Wiederbelebung von Plovdiv, sowie auf dem thermischen und visuellen Komfort, den sie ihren Bewohnern hypothetisch bieten. Um eine mögliche Verbesserung der Gebäudeleistung zu untersuchen, werden fünf Fälle pro Gebäude simuliert - zusätzlich zum Basisfall werden auch vier weitere mit unterschiedlichen Optimierungsoptionen untersucht. Der EEW-Fall umfasst den Ersatz der ursprünglichen Einscheibenfenster durch energieeffiziente und die SW-, H- und EPS-Fälle umfassen die Isolierung der thermischen Hülle der Gebäuden mit Schafwolle, sowie Hanfwolle- bzw. EPS-Isolierung. Alle Fälle werden mit einer parametrischen Simulationssoftware simuliert, um die Wärmeleistung der Häuser zu untersuchen. Die beschriebenen Leistungsindikatoren sind Temperatur und relative Luftfeuchtigkeit, jährlicher Heizwärmebedarf, interne und solare Gewinne, Übertragungs- und Luftwechselverluste sowie die Möglichkeit einer Überhitzung im Sommer. Die Basis- und EEW-Fälle werden verwendet, um das Tageslicht anhand der Beleuchtungsstärke und des Tageslichtfaktors als Schlüsselindikatoren zu bewerten. Die Ergebnisse zeigen, dass die fünf Gebäude in ihrem derzeitigen Zustand eine zufriedenstellende Performance leisten und die aktuellen bulgarischen Energieeffizienzanforderungen erfüllen. Der Austausch von den Fenstern bietet einige Verbesserungen, aber die bedeutendste Änderung kann bei der Isolierung der thermischen Hülle gesehen werden. Von den drei Isolierungstechniken bringt die Schafwollen die größte Veränderung mit sich und ist gleichzeitig eine sehr nachhaltige Option. Auf die andere Seite ändert die Optimierung der Tageslichtdurchlässigkeit nicht signifikant. Die Ergebnisse der Simulationen in dieser Masterarbeit legen jedoch nahe, dass eine Verbesserung der thermischen Hülle die Gebäude in Bezug auf Leistung und thermischen Komfort in Konkurrenz zu den neuesten Technologien bringen würde., The depletion of natural resources in addition to global warming have created the necessity for sustainable development and energy efficiency in almost every aspect of our lives and since construction is one of the main pollutants nowadays, it is important to explore other building practices than the ones we are currently dealing with. The historic buildings of Plovdiv represent the Bulgarian vernacular buildings from the Revival period. They have withstood the test of time, many of which with the same integrity they had decades ago. This has made them very interesting to the architectural community in recent years as they are thought to be one of the founts of sustainable architecture – design with local natural materials and with regard to the environmental context. The main focus of this research is the thermal and visual performance of five Revival period vernacular buildings from the Plovdiv area as well as the thermal and visual comfort they would hypothetically provide to its occupants. In order to explore possible enhancement of the buildings’ performance four cases with different optimization options were simulated in addition to the base case – the EEW case includes replacement of the original single pane windows with energy efficient ones, the SW, H and EPS cases include insulating the thermal envelope with sheep wool insulation as well as hemp wool and EPS insulation respectively. Each building’s five cases were simulated using parametric simulation software in order to explore the thermal performance of the houses. The discussed key performance indicators are temperature and relative humidity, annual heating load, internal and solar gains, transmission and air change losses as well as the possibility of summer overheating. The base and EEW cases were also used to assess daylight using illuminance levels and daylight factor as key indicators. Results show that even in their current state the five buildings perform satisfactorily and do meet the current Bulgarian energy efficiency requirements. The replacement of windows provides some improvement but the most significant change can be seen with insulating the thermal envelope. Out of the three sheep wool brings the biggest change while being a very sustainable option. On the other hand, none of the optimizations change the daylighting situation significantly. However, the study suggests that improving the thermal envelope would put the buildings in competition with the newest technologies in terms of performance and thermal comfort.

One of the main strategies to reduce countries’ energy bills is to invest in efficient buildings. To achieve this objective, the European Union Member States have developed different methodologies to evaluate building energy performance, which are often supported by simulation tools. These tools are based on calculation engines that use databases and simplifications to attempt to bring their results close to real building performance and are mostly designed to be used at the end of the process, neglecting their role in project decision-making processes. To compensate for this situation and to obtain the most accurate results, the methodologies recommend previous work during the building design phase to adopt passive design solutions that learn from experience and aim to adapt the building design to the local climate. However, these design solutions are difficult to adopt while working with medium to large public buildings and are often not properly understood by the simulation tools. In addition, new BIM methodologies are being implemented, starting to enable proper interaction between the designer and the results, and opening up the option of introducing other types of calculations, such as building comfort, in the calculation process. Among the group of countries with limited simulation tools that are starting to be substituted is Spain, which recently launched its first BIM-based energy simulation tool. This tool aims to compensate for the limitations of the former simulation tools and opens up the option of performing comfort calculations by sharing information with other programs. The objective of this research is to evaluate, from different perspectives, the performance of this new simulation tool on three buildings at the University of Alicante. These were chosen as university campuses are responsible for large groups of buildings and belong to the group of stakeholders interested in obtaining efficient and comfortable buildings. These case studies are defined by their extreme adaptation to design recommendations for mild-warm weather. At the end of the process, the difference is measured between simulation and real building performance. The results obtained show that simulation still differs greatly from real building performance from the energy performance point of view, while the comfort evaluation shows results that are closer to the reality of the buildings.

Achieving a satisfactory level for indoor environments of historical buildings is an ongoing problem that needs to be solved due to a large demand for deep retrofits in the whole of Europe. The implementation of the indoor environmental quality index (IEQ) to predict an occupant’s satisfaction in thermo-modernized historical buildings is a new concept which is a response to existing needs. In this article, a relevant study is provided with the intention to evaluate the indoor environmental performance of retrofitting effects in historical buildings dating back to the years 1873–1878. Considering the historical character of the buildings, some of the cellar spaces were fitted out with an innovative internal insulation system of mineral sheets based on calcium silicate to prevent water vapor condensation and effectively limit mold growth. The IEQ methodology was applied for retrofitted and non-retrofitted spaces as a comparison. Four essential components of indoor quality are investigated: thermal comfort, indoor air quality, acoustic comfort, and visual quality. The results of sub-component indexes are calculated based on the measured indoor parameters and the specific sensory functions. This paper discusses the results of an indoor environmental analysis including a mycological air quality assessment with the newly developed IAQindex (fungal air contamination index), total volatile organic compound concentration (TVOC), CO2, and formaldehyde (HCHO) assessment, the evaluation energy-related thermal comfort, acoustic, and visual quality, of modernized spaces. A questionnaire survey study was additionally carried out among a building’s users intentioned to compare the accounts of satisfaction before and after the retrofitting process and also to compare “subjective” results with the one’s based on in situ tests. The retrofitting approach was proven to be effective in limiting the presence of molds and a significant difference in indoor environmental quality between thermally insulated and uninsulated spaces was observed and discussed.

When planning the energy demand of ventilation, proper consideration should be given to the possible scenarios of indoor air quality and pollutant concentrations. The purpose of the present research is to create a practical method of prioritising indoor air pollutants, considering technical, economical and health aspects, in the Indoor Air Quality model (IAQ). In order to find the global weights for the combined IAQindex model sub-elements (in practice, air pollutant concentrations), the Multi-Criteria Decision Making (MCDM) approach is used. The authors have approached the problem of a weighting scheme in a model such as the complex model of the IAQ related to making decisions with many criteria and with the Multi-Attribute Decision Making MADM approach (specifically MCDM). The basis of the MADM method is a decision matrix constructed rationally by the authors, which includes six attributes: actual indoor air carbon dioxide concentration, total volatile organic compounds (TVOCs) and formaldehyde HCHO concentration, and their anthropogenic and construction product emissions to the indoor environment. The decision model of IAQindex includes five alternatives (possible situations), and the combination of pollutant concentration attributes with additional emission attributes is related to the indoor environment under specific situation. For defining the weights of criteria, the authors provide objective approaches: (i) entropy-based approach considering measuring the amount of information, and (ii) CRITIC, a statistic-based approach. The value of the presented method, i.e., the determination of global weights for IAQ components, is shown as a practical application to determine IAQ and the Indoor Environmental Quality (IEQ) index for an office building used as a case study.

Premi Extraordinari de Doctorat, promoció 2018-2019. Àmbit d’Enginyeria Civil i Ambiental The performance of existing buildings is receiving increased concern due to the need to renovate the aging building stock and provide better quality of life for end users. The conservation state of buildings and the indoor environment conditions have been related to occupants’ well-being, health, and productivity. At the same time, there is a need for more sustainable buildings with reduced energy consumption. Most challenges encountered during the analysis of the performance of existing buildings are associated with the complex relationships among the causal factors involved. The performance of a building is influenced by several factors (e.g., environmental agents, occupant behavior, operation, maintenance), which also generate uncertainties when predicting it. Most previous studies that investigate methods to assess a building’s performance do not consider the uncertainty and are often based on linear models. Although different stakeholders’ requirements regarding building performance coexist, few studies centered on the implications of these requirements. Previous studies tend to be highly specific on indicators related to a particular performance aspect, overlooking potential trade-offs that may occur between them. Therefore, a holistic and integrated approach to manage the performance of existing buildings has not been explored. Facility managers need an efficient approach to deal with uncertainty, to manage risks, and systematically identify, analyze, evaluate and mitigate factors that may impact the building performance. Taking into account the aforementioned aspects, the aim of this thesis is to devise a Bayesian network (BN) model to holistically manage the operational performance of buildings and support facility management. The proposed model consists of an integrated probabilistic approach to assess the performance of existing buildings, considering three categories: safety and elements working properly, health and comfort, and energy efficiency. The model also provides an understanding of the causality chain between multiple factors and indicators regarding building performance. The understanding of the relationships between building condition, end user comfort and building energy efficiency, supports facility managers to unwind a causal explanation for the performance results in a reasoning process. The proposed model is tested and validated using sensitivity analysis and data from existing buildings. A set of model applications are discussed, including the assessment of a building’s performance holistically, the identification of causal factors, the prediction of building performance through renovation and retrofit scenarios, and the prioritization of maintenance actions. Case studies also allow to illustrate the applicability of the model for ensuring that its interactions and outcomes are feasible. Scenario analyses provide a basis for a deeper understanding of the potential responses of the model, helping facility managers to optimize operation strategies of buildings in order to enhance its performance. The results of this thesis also include data collection methods for the inputs of the proposed BN model. A building inspection system is proposed to evaluate the technical performance of buildings, a text-mining approach is developed to analyze maintenance requests of end users, and a questionnaire is formulated to collect end-user satisfaction regarding building comfort. To conclude, this work proposes the use of Building Information Modeling (BIM) to store and access building information, which are typically disperse and not standardized in existing buildings. Actualmente, el desempeño de los edificios existentes es de gran interés debido a la necesidad de renovar el stock de edificios antiguos, proporcionando así una mejor calidad de vida a los usuarios finales. El estado de conservación de los edificios y las condiciones ambientales interiores se relacionan con el bienestar, la salud y la productividad de los ocupantes. Al mismo tiempo, existe la necesidad de edificios más sostenibles con un menor consumo energético. El desempeño de un edificio se ve afectado por varios factores (p.ej., agentes ambientales, comportamiento de los ocupantes, operación, mantenimiento, etc.). La mayoría de estos aspectos y causas muestran complejas relaciones, y consecuentemente existe una gran incertidumbre para predecirlo. Sin embargo, las investigaciones anteriores no contemplan estas relaciones causales y, a menudo, se basan en modelos lineales. Aunque el desempeño de los edificios se debe abordar teniendo en cuenta los requisitos de las diferentes partes interesadas, pocos estudios se centran en este enfoque. Los estudios anteriores tienden a analizar aspectos particulares del desempeño, ignorando las posibles relaciones que pueden ocurrir entre ellos. Los gestores de edificios deben abordar eficientemente la incertidumbre, gestionar los riesgos e identificar, analizar, evaluar y mitigar sistemáticamente los factores que pueden afectar el desempeño del edificio. Teniendo en cuenta los aspectos comentados anteriormente, el objetivo de esta tesis es desarrollar un modelo de red bayesiana (BN) para gestionar holísticamente el desempeño operativo de los edificios y apoyar su gestión. El modelo propuesto consiste en un enfoque probabilístico para evaluar el desempeño de los edificios existentes, considerando tres categorías: seguridad y funcionalidad, salud y confort, y eficiencia energética. El modelo también proporciona una interpretación de la cadena de causalidad entre los múltiples factores e indicadores relacionados con el desempeño del edificio. El análisis de las relaciones entre los diferentes aspectos del desempeño de los edificios (estado de conservación del edificio, el confort del usuario final y la eficiencia energética del edificio) va a permitir explicar y entender sus factores causales y va a posibilitar mejorar la gestión de estos edificios. La verificación del modelo propuesto se lleva a cabo mediante análisis de sensibilidad y datos de edificios existentes. Las aplicaciones del modelo incluyen: la evaluación del desempeño de edificios de forma integrada; la identificación de factores causales; la predicción del desempeño de los edificios a través de escenarios de renovación y modernización; y la priorización de las acciones de mantenimiento. La implementación del modelo en diversos casos de estudio permite ilustrar su aplicabilidad y validar su uso. Los resultados de esta tesis también incluyen métodos de recogida de datos para las variables del modelo propuesto. De hecho, se propone un sistema de inspección de edificios para evaluar el desempeño técnico de los edificios, se desarrolla un sistema de text mining para analizar las solicitudes de mantenimiento de los usuarios finales y se formula un cuestionario para recoger la satisfacción de los usuarios finales en relación a los espacios de los edificios en los que interactúan. Para concluir, este trabajo propone el uso del Building Information Modeling (BIM) para almacenar y acceder a la información necesaria para el modelo.

This paper is focused on on the thermal analysis of two models of radiant panels developed and tested in their thermal performances with Comsol Multiphisics. We have to investigated two different configuration, the “coil” panel and the “array” panel defining the design parameters like size and insulation, and analyzing the physical quantities such as flow rate and fluid temperature in the range from 16 to 24°C with a 2°C increment at each stage. The results obtained from the analysis of the thermal flux of panels have demonstrated that this can leads to the determination of the relationship between the heat transfer and the entry speed at different temperatures by using a neural network approach.

İnsanların yaşadıkları mekanlarda sağlıklı ve üretken olmaları, fiziksel ve psikolojik olarak kişileri oldukça etkilemektedir. Bu nedenden ötürü; tüm yapılarda gereken konfor koşulları sağlanmalıdır. Bu konfor koşulları; “yapısal konfor koşulları” olarak nitelendirilmektedir. Yapıda; görsel, iklimsel, işitsel konfor koşulları bulunmaktadır ve yapının planlama ve uygulama aşamalarında göz önünde bulundurulmalıdır. Bu çalışma seçilen yerleşme alanında; bitişik nizamlı villa tipi konutlardaki yapısal konfor özelliklerini tespit etmek amacıyla yapılmıştır. Kullanıcıların konfor koşulları hakkındaki görüşlerini almak üzere bir anket çalışması yapılmış ve bu anket çalışmasında, ısıl konfor, görsel konfor, işitsel konfor vb. konular üzerinde sorular yöneltilmiştir. When people are healthy and productive at places where they live, their physical and psychological situations are effected positively. Because of this; comfort conditions must be got in all buildings. This comfort conditions are “building comfort conditions”. There are visiual, thermal, auditory comfort conditions in buildings and we must be careful in building design and applying ranks. This work is about determinig building comfort features in attached single family houses. For getting ideas from users about comfort conditions, we made inquiry and asked about thermal comfort, visiual comfort and auditory comfort.