The rise in population causes serious issues in larger cities since the electrical grid is becoming overloaded. Simultaneously, the demand on more sustainable energy production and the use of renewable energy sources increase. Renewable energy based off-grid electrical systems are a possible solution to decrease the magnitude of these issues. The purpose of this thesis is to compare solar cells, solar thermal collectors and PVT (Photovoltaic thermal hybrid solar collectors) and design the most suitable combination of solar panels for a selfsufficient multi-family house in Jönköping, Sweden. The solar panels were compared from a cost and energy production perspective, then a suitable renewable energy system with all three types of panels was constructed and optimized using Opti-CE, which is a MATLABbased software. During the course of this thesis, an interview was made with Hans-Olof Nilsson who is a co-founder of Nilsson Energy and owner of a self-sufficient off-grid house. The results show that PVT-panels have higher energy production per area and 22% higher LCC (life cycle cost) than regular solar cells in combination with solar thermal collectors. Optimization results indicate that the house cannot be self-sufficient by installing solar panels on the given roof area only, rather the area of installed solar collectors should be increased to a minimum of 1497𝑚2 . With the given roof area of 900𝑚2 the house can only be self-sufficient a maximum of 75% of the time. The results also indicate that the introduction of compact systems with the simultaneous decrease of cost will make renewable off-grid energy systems more attractive in the future.

La industria de la construcción de viviendas en Lima, tiene como principal característica la aplicación de métodos de construcción tradicionales, basados en construcción in situ. Los procesos constructivos implican una serie de actividades de gran complejidad que muchas veces alteran la producción y dificultan el eficiente empleo de los recursos. Por ejemplo, la alta demanda de mano de obra genera un entorno de incertidumbre en los procesos de producción, por una mayor probabilidad a errores que generan pérdidas. En los últimos años se han hecho importantes esfuerzos para optimizar los recursos y mejorar la eficiencia y el desempeño de la construcción convencional a través de metodologías y herramientas como Lean Construction, BIM, Last Planner entre otros; sin embargo, alcanzados sus máximos posibles, no logran incrementar la productividad ni disminuir los efectos adversos de la construcción tradicional en términos reales a través del tiempo. Por ende, este estudio propone la aplicación de los sistemas constructivos prefabricados altamente industrializados en la construcción del casco estructural de viviendas multifamiliares con el objetivo de elevar la productividad a los estándares internacionales. Del estudio se encontró una reducción del 5% en el costo por metro cuadro de construcción y una reducción en el plazo y el costo de la mano de obra del 26% y 61% respectivamente. Se puede concluir que el método de construcción por prefabricados permite incrementar la productividad dado un eficiente empleo de los recursos como la mano de obra, materiales y el tiempo de construcción. / The main characteristic of the housing construction industry in Lima is the application of traditional construction methods, based on on-site construction. Construction processes involve a series of highly complex activities that often alter production and hinder the efficient use of resources. For example, the high demand for labor generates an environment of uncertainty in the production processes, due to a greater probability of errors that generate losses. In recent years, significant efforts have been made to optimize resources and improve the efficiency and performance of conventional construction through methodologies and tools such as Lean Construction, BIM, Last Planner, among others; however, having reached their maximum possible levels, they fail to increase productivity or reduce the adverse effects of traditional construction in real terms over time. Therefore, this study proposes the application of highly industrialized prefabricated construction systems in the construction of the structural hull of multi-family homes with the aim of raising productivity to international standards. The study found a 5% reduction in the cost per square meter of construction and a reduction in the term and cost of labor of 26% and 61%, respectively. It can be concluded that the prefabricated construction method allows increasing productivity due to an efficient use of resources such as labor, materials and construction time. / Tesis

I have designed a housing project that is an infill to an existing housing block in the city center of Stockholm. When I started this project the themes everydayness and building typology was central for me. That is why I also chose to work with the site Sälgen 4; a corner site and one of few remaining gaps in the block structure of the city center. Today there is a gas station on the site, which I for this project presume could be removed. When working with this project I found interest in what simplified could be called soft flexibility, where measurement, shape and connection to other spaces are dealt with in order to enable for different kinds of usage. This type of flexibility I encountered when studying late 19th century dwellings in Stockholm city center. I have developed similar apartments, often with a size of about 140 m2 with 4,5 rooms and an additional kitchen. Even all the room units are similar with over 4 m width and close to square shapes. This enabled the creation of very generic spaces but also introduced me to an interesting paradox; the on the architectural drawing less dynamic floor plan create on the other hand the most dynamic ways to inhabit the spaces. Also the loggia has been an important feature in my design. / Jag har ritat ett bostadshus som är ett infill till ett befintligt kvarter i Stockholms innerstad. När jag började projektet så var temana vardaglighet och byggnadstypologi viktiga för mig. Därför valde jag att arbeta med tomten Sälgen 4; en hörntomt och en av få luckor i kvartersstaden. Idag finns där en bensinmack men jag har sett det som en förutsättning för projektet att den kan tas bort.   Under projektets gång har jag intresserat mig för vad som förenklat kan kallas för mjuk flexibilitet, där rummens mått, form och angöring möjliggör för många olika typer av användning. Den typen av flexibilitet upptäckte jag då jag studerade gamla sekelskifteshus i Stockholm   Jag har arbetat fram likartade lägenheter på oftast runt 140 m2 med 4,5 rum och kök. Även rumsenheterna är nästan identiska med drygt 4 m i bredd och nära kvadratisk form. På så vis har jag skapat en hög grad av generallitet men också konfronterats med en spännande paradox; de å ena sidan som ritning minst dynamiska planerna, kommer å andra sidan att generera den mest dynamiska och tillåtande användningen av dem. Även loggian har varit ett viktigt inslag i min design.

Nuestro proyecto busca demostrar que se puede mejorar el desempeño sísmico de las edificaciones empleando aisladores sin afectar la rentabilidad del proyecto. Para ello, se evaluó aplicarlo en el proyecto “Residencial Hungría” el cual se trata de un edificio multifamiliar de 12 departamentos y 10 estacionamientos distribuidos en 4 pisos y un semisótano respectivamente. Se modifico la configuración original del proyecto y se incluyó un sistema de aisladores de base con núcleo de plomo con el fin de comparar la rentabilidad entre ambos proyectos (Original y modificado con aisladores). Los resultados obtenidos en la primera etapa muestran que ante un número reducido de pisos (04 pisos) la rentabilidad del proyecto modificado con aisladores es menor a la original, sin embargo, luego de evaluar múltiples opciones, se obtuvo que a partir de 07 pisos tiene un VAN de S/ 172,077 un TIR de 24 % mayor al COK que es de 20%. Sabemos que en la Filosofía y Principios del Diseño Sismorresistente contenidos en la Norma E.030 del Reglamento Nacional de Edificaciones se reconoce que dar protección completa frente a todos los sismos no es técnica ni económicamente factible para la mayoría de las estructuras, es por ello por lo que el uso de los aisladores está enfocado principalmente a estructuras del sector salud y educación. Con esto proyecto queremos propiciar la aplicación de aisladores a más proyectos de edificaciones y viviendas multifamiliares, verificando que, si puede ser rentable económicamente para el constructor, lo cual beneficiaría la demanda desatendida de la población que requiere una vivienda más segura y con mejor desempeño ante un sismo, y que minimice los costos de reparación, muertes y damnificados ante un eventual movimiento sísmico de alto impacto aun teniendo que invertir un porcentaje adicional en la compra del inmueble. / This research demonstrate that the seismic performance of buildings can be improved by using isolators without affecting the profitability of the project. For this, it was evaluated in the "Residential Hungria" project, which is a multifamily building with 12 apartments and 10 parking spaces distributed in 4 floors and a semi- basement, respectively. The original configuration of the project was modified and a system of base insulators with lead core was included in order to compare the profitability between both projects (Original and modified with insulators). The results obtained in the first stage show that with a reduced number of floors (04 floors) the profitability of the project modified with insulators is lower than the original one, however, after evaluating multiple options, it was obtained that from 07 floors it have a NPV of S / 172,077 an IIR of 24% higher than the COK which is 20%. We know the Philosophy and Principles of Earthquake Resistant Design contained in Standard E.030 of the National Building Regulations, it is recognized that providing complete protection against all earthquakes is not technically or economically feasible for most structures, which is why isolators is mainly focused on structures in the health and education sectors. With this project we want to promote the application of insulators to more projects of buildings and multifamily housing, verifying that, it can be economically profitable for the builder, which would benefit the unattended demand of the population that requires a anti seismic building prepared for an earthquake, minimizes repair costs, deaths and victims in eventual high-impact seismic movement even having to invest an additional percentage in the purchase of the property. / Trabajo de investigación

Lima es el principal escenario de desarrollo de proyectos de vivienda, por ello es una importante fuente de oportunidades para las empresas constructoras. Un significativo porcentaje de estas lo conforman pequeñas y medianas empresas, que buscan estrategias para competir en el mercado. Por ejemplo, la canalización de sus actividades a través de la subcontratación. En este escenario, suelen presentarse dificultades en el proceso de valorización de los subcontratistas de las partidas de acabados, dado que son tareas que requieren de mayor tiempo y detalle para validar. Estos problemas son resueltos de manera sintomática porque no se trabaja con herramientas que permitan anticiparlos ni entenderlos en su totalidad. El objetivo de la presente investigación es desarrollar una propuesta de solución frente a los problemas identificados, a través de la implementación de una herramienta de programación visual (Dynamo) dentro de un entorno de trabajo BIM, que permita optimizar el tiempo en el proceso de valorización de subcontratistas de acabados en edificios multifamiliares menores de 10 pisos de NSE A y B ejecutado por una PYME constructora en Lima Metropolitana. Se realizaron entrevistas a profesionales encargados de realizar las valorizaciones para identificar las principales deficiencias que se presentan en este proceso y de esta forma, plantear la propuesta de solución. Finalmente, se realizó la validación de la propuesta de solución a través del juicio de expertos, como resultado de las opiniones emitidas por estos y su nivel de interés percibido se concluyó que la propuesta sería de gran aporte en una posible implementación. / Lima has been the main scenario for the development of building projects, which makes it an important source of opportunities for construction enterprises. A significant percentage of these are made up of small and medium-sized enterprises (SMEs), which constantly seek strategies to compete in the construction industry. One of these is assigning their activities through subcontracting. In this common practice, difficulties often arise in subcontractor’s schedule of values of finishes process, since they are tasks that demand more time and detail to track the progress, even more critical situation in projects with a reduced site-based staff. These problems are solved symptomatically because they do not work with tools for anticipate or understand them entirely. The objective of this research is to develop a proposed solution to the problems identified, through the implementation of a visual programming tool (Dynamo) within a BIM environment, for optimize time in subcontractor’s schedule of values of finishes process in less than 10-story multi-family buildings of Socioeconomic Status A & B executed by a construction SME in Metropolitan Lima. In order to identify the main deficiencies that appears in traditional process, interviews were conducted with in-charge professionals of subcontractor’s schedule of values of finishes. Then, collected information was analyzed to propose a solution for the problem. Finally, the proposed solution was validated through expert judgment, which through the opinions expressed by the professionals and their perceived level of interest, it was concluded that the proposal would be of great contribution in a possible implementation. / Tesis

This study has been conducted in cooperation with OBOS Kärnhem. The objective of the study is to assess environmental impacts from different structural and facade materials to find a configuration with the lowest impact, and to assess the economic implications of different structural and façade materials. The study is conducted on a case study building planned in Linköping, Sweden. The methods that were used are the life cycle assessment (LCA) and life cycle cost (LCC) methods. Cross-laminated timber and concrete were chosen as the 2 structural materials to investigate, and sheet metal, cut slate, and wood paneling were chosen as the façade materials to investigate. The goal and scope were specified. The goal of the LCA was to analyze the climate implications of different structural and facade materials on a building’s environmental performance, while the scope was to compare the environmental impacts, specifically global warming potential, of six scenarios over a lifetime of 80 years. Later, a life cycle inventory of the materials was conducted, and the life cycle inventory was assessed. Finally, the life cycle interpretation was carried out to analyze and interpret the results. For the LCC, costs were calculated for materials and energy use and applied to the case study building. The analyses of results show that the wooden building scenarios have significantly low environmental impacts when compared with concrete buildings. The analyses of the results also show that the buildings constructed with cast-in-situ concrete have lower life cycle costs when compared with buildings constructed with cross-laminated timber. This study concludes that structural material choices affect the environmental performance of a building significantly. Facade material choices also affect the environmental performance, however much less significantly. This study also shows that, within these specific system boundaries, the most impactful life cycle stage for the wood structure building scenarios is the operational phase B6, while the most impactful life cycle stage for the concrete structure building scenarios is the material production stage A1-A3. This study further concludes that while cross-laminated timber buildings have a lower carbon footprint than concrete structure buildings, they currently cost significantly more to build. This highlights the discrepancies between the changes and choices that are required to reach the climate and sustainable development goals, and what is economically viable.

District heating plays a major role in the Swedish energy system. It is deemed a renewable energy source and is the main provider for multi-family dwellings with 90 %. Although the district heating fuel mix consists of majority renewables, a share of 5 % is provided from fossil fuels. To reduce fossil fuel usage and eradicate CO2-emissions from the district heating system new solutions are sought after. In this project, the potential for shortterm thermal energy storage in buildings is investigated. This concept is referred to as customer flexibility. Demand flexibility is created in the district heating system (DHS) by varying the indoor temperature in 50 multi-family dwellings with maximum 1◦C, without jeopardizing the thermal comfort for the tenants. The flexible load makes it possible to store energy shortterm in the building’ envelope. Consequently, heat load curves are evened in production. This leads to a reduction of the peak load in the DHS. Peaks are associated with high costs and environmental impact. Therefore, the potential benefits of customer flexibility are reduced peak production, fuel costs, and CO2-emissions, depending on the fuel mix in the DHS. The project objective is to examine the techno-economic potential of customer flexibility in a specific DHS. The case study is made in a DHS owned by the company Vattenfall, located in the Stockholm area. To evaluate the potential benefits of implementing the concept, seven key performance indicators are chosen. They are peak power, peak fuel usage, produced volume, total fuel cost, fuel cost per produced MWh, climate footprint, and primary energy. Moreover, an in-house optimization model is used to simulate multiple scenarios of the district heating DHS. Different sets of assumptions about the available flexibility in the DHS and the thermal characteristics of the buildings are made. Customer flexibility is modeled as virtual heat storage that can be charged up or down depending on the speed and size of the available storage at a specific outdoor temperature. Simulation results give a maximum peak power reduction of 10.9 % and annual fuel cost reduction between 0.9-3.6 % depending on the scenario. The results found are comparable to values found in similar studies. However, the environmental key performance indicators generated an increase in CO2-emissions and primary energy compared to the baseline scenarios. The result would have looked different if fossil fuels were used in peak production instead of biofuels. The master thesis also aimed to validate assumptions and parameters made in the input data to the optimization model. This was achieved by using results attained from a pilot in the specific DHS. Therefore results generated from the simulations are deemed accurate and confirm that customer flexibility leads to reduced peak production and DHS optimization. / Se filen

Aging buildings will sooner or later be in need of renovation, which opens opportunities to reduce energy use. Even if economically feasible energy measures or technologies exist, they are not always implemented, leading to an energy efficiency gap. This dissertation deals with how energy measures are handled and why they are enabled or disabled during the planning and design of renovations. During renovations, different kinds of building professionals are engaged, here referred to as middle professionals. The meeting practice of the professionals is investigated, with a focus on how the middle professionals exert influence from the middle-out and to the top and bottom, and how and why they enable or disable measures aimed at energy efficiency or reduction. Three renovation projects are followed in the municipality-owned housing company Stångåstaden, in Linköping, Sweden. The housing company’s goal is to reduce the amount of purchased energy by 25% by 2025. Methods applied during the research are semi-structured interviews, participant observations and document analysis. The conclusions show that energy measures were implemented, but more can be done in renovations. Predefined meeting agendas make the process efficient but not flexible, thus it can be difficult to introduce innovations and alternative ways of thinking into the process. The professionals usually selected measures they had used before. Energy calculations attracted little interest compared to the aggregated knowledge from previous projects, and experience and tacit knowledge were highly valued. This and more lead to a renovation process where it is difficult for energy to enter the current meeting practice. / Byggnader behöver förr eller senare renoveras, vilket ger möjligheter att minska energianvändningen. Existerande energieffektiva och lönsamma åtgärder genomförs emellertid inte i tillräcklig utsträckning, det så kallade energieffektiviseringsgapet. Avhandlingen handlar om implementering av energieffektiviseringsåtgärder vid renovering av flerfamiljshus och varför vissa åtgärder genomförs medan andra väljs bort. I avhandlingen undersöks hur de professionella i mitten av beslutshierarkin, kan påverka implementeringen av energieffektiva åtgärder uppåt och nedåt i en organisation men även utåt, i en horisontell riktning. Undersökningen rör de professionella aktörernas inflytande i planerings- och designfasen, och hur de fattar beslut om att inkludera eller exkludera energieffektiva åtgärder. Studien omfattar tre renoveringsprojekt i det kommunägda bostadsbolaget Stångåstaden i Linköping. Bostadsbolagets mål är att minska mängden köpt energi med 25% till år 2025. Studien bygger på semistrukturerade intervjuer, deltagande observationer och dokumentanalys. Slutsatserna är att även om bostadsföretaget genomför energiåtgärder, kan mer göras i renoveringsprocesser för att förbättra energieffektiviteten. Förbestämda agendor på projektgruppsmötena gör processen effektiv men inte flexibel, och det kan vara svårt att introducera innovationer och alternativa sätt att tänka kring energi. De professionella i mitten valde oftast åtgärder som de tidigare hade använt, energiberäkningar spelade en liten roll och erfarenhetsbaserad kunskap värderades högt. Allt detta och mer leder till en renoveringsprocess där det är svårt att föra in energi i dagens mötespraktik.

Energianvändningen idag är den största bidragande faktorn till de globala klimatförändringarna vilket ställer krav på mer hållbar och resurseffektiv energihantering. I Sverige står sektorn bostäder och service för ca 40 % av den slutgiltiga energianvändningen motsvarande 144 TWh. För att nå en mer hållbar byggnadssektor har EU i direktivet för Byggnaders Energiprestanda satt målet att byggnadssektorn ska vara fossilfri till 2050, samt beslutat att varje medlemsstat ska etablera en långsiktig renoveringsstrategi. Nationellt finns därmed målet att minska den totala energianvändningen per uppvärmd area med 50 % till 2050 jämfört med 1995. Detta innebär att omfattande energieffektiviseringsåtgärder (EEÅ) behöver implementeras i Sveriges byggnadsbestånd. I examensarbetet jämförs den nationella potentialen avseende energibesparing, kostnadseffektivitet samt utsläppsreduktion av koldioxidekvivalenter (CO2eq) för olika energieffektiviseringsåtgärder (EEÅ) kopplade till uppvärmning och tappvarmvattenanvändning i flerbostadshus. Vidare undersöks även hur väl anpassade befintliga styrmedel är för de studerade EEÅ. För att besvara frågeställningarna har sex olika typhus tagits fram vilka är representativa för Sveriges bestånd av flerbostadshus. Dessa byggnader har modellerats i programvaran IDA ICE och energisimuleringar har genomförts för att undersöka effekterna av samtliga EEÅ. Vidare, styrmedel kopplade till energieffektivisering av flerbostadshus har analyserats och dess innebörd för olika EEÅ granskats. Resultatet visar att inom det svenska flerbostadshusbeståndet har installation av spillvattenvärmeåtervinning och FTX störst tekniskt möjlig energibesparingspotential med en årlig nationell energibesparingspotential på 5,3 TWh respektive 4,7 TWh. Isolering av tak är den EEÅ med högst kostnadseffektivitet per sparad energienhet, 334–579 SEK/MWh beroende på klimatzon, följt av spillvattenvärmeåtervinning och FTX som har en kostnadseffektivitet på 1267–1503 SEK/MWh respektive 1882–3587 SEK/MWh. Takisolering är även den EEÅ som är mest kostnadseffektiv för utsläppsminskning av koldioxidekvivalenter följt av spillvattenvärmeåtervinning och FTX. För takisolering är kostnadseffektiviteten 5,9–10,3 tSEK/ton CO2eq, 28,2–33,5 tSEK/ton CO2eq för spillvattenvärmeåtervinning och 39,5–93 tSEK/ton CO2eq för installation av FTX. Utifrån de styrmedel som studerats konstateras det att befintliga styrmedel för energieffektivisering i flerbostadshus inkluderar konventionella EEÅ men att det finns bristfällig information och krav gällande återvinning av värme från spillvatten trots åtgärdens höga energibesparingspotential och kostnadseffektivitet. Bättre kunskap och information gällande kostnadseffektiviteten för olika EEÅ kan leda till mer resurseffektiva åtgärdsförslag från energiexperter och även öka renoveringstakten. / Today's energy use is the largest contributing factor to global climate change, which calls for a more sustainable and resource-efficient energy management. In Sweden, the residential and service sector accounts for about 40% of the final energy use, corresponding to 144 TWh. To achieve a more sustainable building sector, the European Commission has set a target in the Energy Efficiency Directive that the building sector should be fossil-free by 2050 and decided that every Member State should establish a long-term renovation strategy. Nationally, there is a target to reduce the total energy use per heated area by 50% by 2050. This requires a large-scale implementation of energy efficiency measures (EEMs) in Sweden's building stock. This master thesis compares the national potential regarding energy saving, cost-effectiveness and emission reduction of carbon dioxide equivalents (CO2eq) for various EEMs linked to heating and domestic hot water use in multi-family buildings. Furthermore, it is also examined how well-adjusted existing policy instruments are to the studied EEMs. To answer the research questions, six different reference buildings, which are representative of Sweden’s stock of multi-family buildings, have been developed. These buildings have been modeled using the software IDA ICE and energy simulations have been carried out to investigate the effects for all EEMs. Policy instruments regarding energy efficiency in multi-family buildings have been analyzed and their significance for various EEMs have been investigated. The results show that installation of wastewater heat recovery and exhaust air heat recovery has the highest technically possible energy saving potential with an annual national saving potential of 5.3 TWh and 4.7 TWh, respectively Roof insulation is the EEM with the highest cost-effectiveness per saved energy unit, 334–579 SEK/MWh depending on climate zone, followed by wastewater heat recovery with a cost-effectiveness of 1267–1503 SEK/MWh and exhaust air heat recovery with 1882–3587 SEK/MWh. Roof insulation is also the EEM that is most cost-effective regarding reduced CO2eq -emissions, followed by wastewater heat recovery and exhaust air heat recovery. For roof insulation, the cost-effectiveness is 5.9–10.3 kSEK/ton CO2eq, 28.2–33.5 kSEK/ton CO2eq for wastewater heat recovery and 39.5–93 kSEK/ton CO2eq for installation of exhaust air heat recovery. Based on the studied policy instruments, it is found that the existing policy instruments for EMMs in multi-family buildings include conventional EMMS. However, there is insufficient information and requirements regarding recovery of heat from wastewater despite the measure's high energy saving potential and cost-effectiveness. Better knowledge and information regarding the cost-effectiveness of various EEMs can lead to more resource-efficient suggestions from energy experts and increase the pace of renovation.

This project investigated the sustainability of homes within three intentional communities. Semi-structured interview and photographic walkthroughs examined the variability of architectural and technological approaches toward sustainability. These include: passive solar design, green roofs, radiant flooring, composting toilets, ground assist heat pumps, solar water heaters, multiamily units and modular construction. It was hypothesized that variation in sustainable construction is related to socioeconomic status and that economics would be a constraint. This project investigated whether communities were transmitting their practices to wider society, if individuals were copying vernacular architecture and if architectural practices followed individual beliefs regarding sustainability. It was found that the Internet is the main method of conveying these practices; that variability was tied less to individual beliefs than to the communities’ institutional documents; and that copying vernacular architecture was for aesthetics not sustainability. Intentional communities are good models for sustainable development, but knowledge transmission is limited.