Abstract The Building sector is today an important sector in our society, which means that more people move from the urban area to the big cities, which in turn increases building production. The building and service sector is the largest energy waste in Sweden and internationally, which is about 40% of Sweden's total energy use and 60% of that energy goes to heating. The EU Directive Energy Performance of Buildings Directive (EPBD), implemented the concept of near zero-energy houses, which comes into full force in 2020, which means that all newly-built buildings must be energy-efficient with better energy performance than todays buildings. This is in connection with the need of houses/buildings and rental costs continuing to increase. For this reason, Ljusbo Hyreshus AB has invented a solution that includes both climatesmart rental apartments and cheap rental costs, which has attracted more than 20 communes (kommuner in Sweden) to offer land for these apartments. The purpose of this thesis is to find out the energy performance of one of Ljusbo Hyreshus AB's prototype module houses. Furthermore, improvement proposals would be developed to make the module house more energy efficient. The prototype house consisted of a single-storey modularhouse that stay in Söderhamn, which has been chosen in this thesis for further investigations. The house had a total area of 45 m2 and consisted of 3 rooms and kitchen. In this case study, the energy performance has been developed using analysis methods in the form of hand calculations and the energy signature method. Subsequently, the result of the analysis would be validated and would form the basis for later identification of various energy efficiency measures that contributed to the reduction of energy performance in the house and thereby achieved the passive house standard. The result shows that the modularhouse does not fullfil BBR's requirements at present, because the house misses important components which is important for energy performance. For this reason, improvement proposals, specifically regarding the climate shell, on energy efficiency measures have been developed in this report. With the help of these energy efficiency measures, which mainly consist of additional insulation and energy-efficient windows and with an energy-efficient ventilation system with heat recovery (FTX) and an installed air-water heat pump, the passive house standard has been possible to achieve. Future measures, such as the installation of solar cells, have also been examined in the report. This is due to converting the building from a passive house to a plus energy house.

Aktuellt examensarbete är en fallstudie som utförts på en miljonprogramsbyggnad i Andersberg ägd av AB Galvegårdarna vilka även är uppdragsgivarna. Då miljonprogramsbyggnader är dåligt värmeisolerade och har stora värmeläckage är det idag av stort intresse att se över eventuella förbättringsåtgärder då dessa byggnader har en potential att minska energianvändningen med 50 procent. Syftet med detta projekt är att få en kalibrerad och validerad modell med hjälp av den BES-modell (Building Energy System) som kommer att tas fram i detta examensarbete. Genom litteraturstudie, platsbesök samt inhämtning av protokoll, ritningar och uppmätta data för byggnaden kunde modellen skapas och kalibreras i simuleringsprogrammet IDA Indoor Climate and Energy. Ritningar och data tillhandahölls från AB Gavlegårdarna och platsbesök gjordes för att komplettera dessa genom att göra mätningar av temperaturer i de allmänna utrymmena. På plats kunde även byggnadens mått mätas för att säkerställa att byggnaden inte hade uppdaterats sedan tilldelade ritningarna skapats. När samtlig information ansågs ha införskaffats lades all data in i IDA ICE där även en modell av byggnaden byggdes upp. För köldbryggorna användes simuleringsverktyget COMSOL Multiphysics för att ta fram de enskilda köldbryggornas psi-värden vilka därefter användes som input i byggnadsmodellen i IDA ICE. Den kalibrerade modellen framtagen i detta projekt visade sig stämma med uppmätta värden så när som på +- 10% då den ställdes mot det uppmätta energibehovet för byggnaden. Mot en nyutvecklad energisignatursmodells byggnadsförlustkoefficient blev skillnaden 19.6% vilket kan bero på att fel från simuleringsverktygen samt osäkerheter angående omätbara parametrar. Slutsastsen utav detta arbete var att ”performance gap” även inträffade på den framtagna modellen i detta arbete. Vilket verkar vara svårt att undvika. På platsbesöket upptäcktes vattensamlingar på taket på byggnaden vilket var en förvåning för författarna då det fanns dokument som sade att ytskiktet var bytt 2015 och att det fanns indikeringar på att detta kunde få omfattande konsekvenser om det inte åtgärdas vilket tas upp under diskussion Framtida arbete om varför boendes bettendemönster underskattas vore något att gå vidare med i framtida studier för att kunna minska ”performance gap” på BES modeller. / This thesis is a case study carried out on a Million Homes Program (MHP) building in Andersberg owned by AB Galvegårdarna, whom are also the clients. Since MHPbuildings are poorly insulated and have major heat leaks, it is of great interest today to investigate any improvement measures as these buildings have a potential to reduce their energy use by 50 percent. This is possible with the help of the calibrated model in a building energy performance simulation (BEPS) tool, which is the purpose of developing in this thesis. Through a literature study, visit in the building and gathering protocols, drawings and measured data, a model could be built and calibrated in IDA Indoor Climate and Energy was started. Drawings and data were provided from AB Gavlegårdarna and site visits were made to supplement these by taking measurements of temperatures in the common areas. On site, the dimensions of the building were also measured to ensure that the building had not been upgraded since the assigned drawings were created. When all the information was considered to have been obtained, all data was entered into IDA ICE where a model of the building was also built up. For the thermal bridges, the COMSOL Multiphysics simulation tool was used to generate their individual linear heat loss coefficient which were used as input in the building model of IDA ICE. The calibrated model developed in this project turned out to have a deviation of 10 % against annual district heating energy. The simulated building heat loss coefficient differed with 19.6 % compared to the one produced with a newly developed energy signature method for the corresponding year which may be caused by errors in the simulation tools and uncertainty concerning immeasurable parameters. The final conclusion of this work was that the performance gap also occurred on this model developed in this work, which seems to be hard to avoid. During the site visit, water collections on the roof of the building were discovered which was a surprise to the authors as there were documents that said that the surface layer had been changed in 2015 and that there were indications that this could have significant consequences if not addressed which is mentioned in the chapter of discussion. Future work on why residents’ behavioral patterns are underestimated would be something to continue with in future studies in order to reduce the “performance gap” in BES models.