When thinking of renovating the windows of old buildings, the building owner has a lot of decisions to make. These are to keep the window but make it more energy efficient by adding an extra pane or to completely change the whole window. At the same time, the joint between the window frame and wall makes a thermal bridge which depends on how much insulation has been placed in the cavities after installation. Upon the decision of keeping the window, the status of this joint will be unchanged. This thesis deals with finding out the best economical solution for a company that has rental apartments in Gävle in Sweden, Gavlegårdarna AB. To calculate the thermal bridges, which are weak areas of the building envelope in which they significantly increase the energy load of houses, a CDF program called Fluent is used to quantify the heat loss at the joints. Measurements have been performed to validate the CFD model. To simulate the energy savings in the building, the building energy simulation program IDA-ICE is used. Finally, Life Cycle Costing calculations are made to assess the best long term economical option. It is concluded that the most reasonable solution is to add an extra glass in the existing window, but it is not the most ecofriendly. A more ecological solution is to add the extra glass and to perform enhanced insulation at the joints around the window frames and walls, or to replace the old window with a new low energy window – however, these are not profitable so

L'utilisation massive des énergies fossiles est en grande partie responsable des émissions de gaz à effet de serre. De plus, la croissance de la demande énergétique et la raréfaction des ressources fossiles conduisent à l'accroissement du coût de l'énergie. La réponse à cette problématique passe par deux moyens d'action indissociables : la réduction des consommations énergétiques et le recours aux énergies renouvelables. La fenêtre pariétodynamique permet d’agir sur les deux postes principaux de déperdition thermique d’un bâtiment que sont les baies et la ventilation. Le principe de la fenêtre pariétodynamique étudiée est de faire circuler de l’air en convection forcée entre trois verres avant d’être restitué à l’ambiance intérieure du bâtiment. Cela permet à l’air de récupérer à la fois une partie des déperditions thermiques à travers la fenêtre et une partie de l’énergie solaire absorbée par les verres. Afin d’étudier le comportement thermo-aéraulique et les performances de la fenêtre, nous avons développé un modèle numérique de cette dernière. Un dispositif expérimental a été mis en place et utilisé afin de valider le modèle numérique et de comparer en conditions réelles les performances de la fenêtre étudiée à celles d’une fenêtre à double vitrage classique. Ces résultats expérimentaux ont été complétés par une étude paramétrique numérique réalisée pour différentes conditions climatiques et de fonctionnement. Les principaux enseignements issus de ces études expérimentales et numériques sont que le préchauffage de l’air se fait essentiellement dans la lame d’air intérieure, la température de la première lame d’air restant proche de celle de l’air extérieur. De plus, et contrairement aux températures de la face intérieure et de l’air soufflé, celle de la face externe de la fenêtre est peu impactée par les paramètres étudiés. Concernant le cadre de la fenêtre, nous avons observé que celui-ci bénéficie aussi des échanges thermiques avec l’air circulant, mais dans une moindre mesure. Cela contribue à rendre la fenêtre peu déperditive. Enfin, en couplant le modèle développé à un logiciel de simulation thermique dynamique, nous avons évalué le potentiel d’intégration de fenêtres pariétodynamiques dans une maison individuelle. Nous mettons ainsi en évidence que le besoin de chauffage est réduit d'environ 20 à 30 % par l’utilisation de fenêtres pariétodynamiques à la place de fenêtres à double vitrage classique. En été, si l’ambiance intérieure du bâtiment est plus fraîche que l’environnement extérieur, la fenêtre pré-rafraîchit l’air neuf entrant. / The massive use of fossil energies is largely responsible for greenhouse gas emissions. Moreover, the growth in energy demand and the depletion of fossil resources lead to an increase in energy costs. The response to this challenge requires two means of action which are linked : the reduction of energy consumption and the use of renewable energy. The airflow window acts on the two main ways of building heat losses that are windows and the ventilation. The principle of the studied airflow window is based on the circulation of fresh air, by forced convection, between the three glasses of the window before entering the building. This allows air to recover both a part of heat losses through the window and part of the solar energy absorbed by the glasses. To study the thermo-aeraulic behavior and thermal performances of the window, we have developed a numerical model of the studied airflow window. An experimental set up was used to validate the numerical model and compare, in real conditions, the studied window performances to the ones of a conventional double-glazed window. These experimental results were complemented by a numerical parametric study for different climatic and operating conditions.The main information from these experimental and numerical studies are that the preheating of the air takes place essentially in the inner air gap, temperature in the first air layer remaining close to the outdoor one. In addition, unlike the temperatures of the inside face and of the blown air, the outer face temperature of the window is not greatly affected by the studied parameters. On the window frame, we found that it also benefits of heat exchanges with the circulating air, but to a lesser extent. This makes the window energy efficient. Finally, by coupling the developed model to a thermal building simulation software, we evaluated the airflow windows integration potential in a house. We thus demonstrated that the heat load is reduced by about 20 to 30% by the use of airflow windows instead of conventional double-glazed windows. Moreover, in summer, when indoor is cooler than outdoor, we pointed out that the airflow window cools the incoming fresh air.

Due to the geographical location, the amount of daylight in Sweden varies greatly during the year - the lack of light is part of our everyday life. Regardless of the season, the sun’s position gives a light that seems to fall from the side, it kind of drags itself in through the windows. As a result, it is easily influenced by the surroundings. All the edges, corners and profiles that stand in the way create an endless variety of shades. Given these conditions, it is a good reason to devote time to the detailing of all the parts of a window. In this master’s project, I am directing my gaze towards the window frame and more specifically towards the framework’s profiling. By observing the shape and the color language of different profiles, the perceived contrast between light and shades is noticed and interpreted into new. Based on the qualities of the Nordic light, this project hopes to clarify and show with concrete examples why decision-making around the window frame is crucial for how we perceive the incident light. Relatively small differences in profiling create a large effect in contrasts, I find, and consequently, a more complex window profile enhances the character of the window and the incident light. This project is about looking at something specific, to observe and to explain what already is there.

No / Methods of recycling unplasticized polyvinyl chloride (uPVC) window frame waste were investigated. The quality of untreated granular waste was compared to that of waste treated by a range of contaminant removal processes including melt filtration and dissolution. Processability of each recyclate was evaluated by using a highly instrumented single screw extruder that enabled melt viscosity and process variation to be monitored in real time. Product quality measurements such as mechanical properties and surface defects were made on extruded strip, and the nature of the stabilizers present was determined. The mechanical properties of recyclates were found to be comparable to or better than those of virgin material in all cases and conformed to industry standards for window profile. Contaminant removal stages significantly reduced the amount of large surface defects detected in extrudate. Processability was comparable to that of virgin compounds, but melt viscosity varied among different batches of recyclate, depending on the source and composition of the original PVC formulation.

The dissertation thesis is focused on a methodology of optimal design energy renovation of school buildings. The thesis is focused on the analysis of selected school buildings during the last 100 years of construction in the first phase. At this phase, are found some important information, especially in terms of the energy performance of the building envelope and results of this parts. Last but not least, CO2 emissions were detected. In the next part of this work, one selected school is assessed in terms of the quality of the environment, due to the evaluation of microbial microclimate on building structures, CO2 concentration and daylight. CO2 concentration and classroom daylight is addressed both for the original and for the new state. Another point of this thesis is the appreciation of the size of the classrooms in the schools both in terms of typological principles and in terms of the average size of classrooms. The daylight assessment is performed on these selected sizes, which is a part of the "PaMo I" design tool. In the next phase of the dissertation was created the design tool "PaMo I". This tool solves the evaluation of the renovation of school buildings from the point of view of the thermal engineering in connection with the influence of the daylight illumination on the classrooms of the school buildings by the thickness of the insulation system and the replacement of the windows. Part of the design tool is also the financial quantification of the investment, the payback period and the impact on the environment of the individual variants. The choice of variant options has been used when making a design tool user decision. The result of this work is a design tool which will help in deciding and finding the optimal alternative to the energy renovation of a school building in connection with daylighting inside classrooms.