The building sector has attributed a significant focus on improving its sustainability performance, as it contributed to almost 38% of global carbon dioxide emissions in 2019, and is estimated to be the least environmentally friendly industry worldwide. Life cycle analysis (LCA) is considered a rewarding method for evaluating the environmental impact caused by buildings or individual building components, based on various environmental indicators such as carbon dioxide emissions. A life cycle analysis can be performed in different ways depending on the purpose of the analysis. Screening LCA is a method which can be used to get an overview of the environmental impact associated with different life cycle stages. The method accounts for the environmental impact caused by value chain and the physical flow in production of materials and systems. This method can also be useful to analyze the carbon footprint of a building during its production phase, A1-A3, and transports of materials to the construction site, A4. This can enable to peruse and reduce building’s carbon footprint by replacing materials with more environmentally friendly ones before the building is built.Besides the aesthetical benefits, green solutions such as green facades (or living facades) can create the possibility to obtain more environmentally friendly buildings. Although green facades are not a new concept, such system has increasingly been adopted on the facades of buildings in recent years. While, it has been proven that green facades have the ability to absorb pollutants and carbon dioxide from the air, their production serves additional CO2 emissions.This study has been conducted in collaboration with Ramboll Sweden AB, the division of sustainable buildings. The study aims to increase knowledge regarding green facades and their impact on the exterior walls, both thermally and environmentally. In the study, 8 models were created and analyzed to explore the CO2 impact of green facades on different alternative exterior walls. In this study, an LCA was performed, and the impact of living facades on the heat transfer coefficient, the U-value, was analyzed for each of which models. Furthermore, an estimation of possible carbon dioxide capture by green facades was carried out to explore the potential benefits of such facade systems from a life cycle perspective.The results show that a living façade can result in approximately 27.9 kgCO2e/m2 compared with an exterior wall without a living façade. However, the ability of such facades to capture carbon dioxide can make it possible to compensate this additional carbon dioxide emission during almost 93 years, if a linear CO2 capture is assumed.

Ett stort antal av miljonprogrammets byggnader är idag i behov av renovering. Då många av dessa byggnader har en hög energiförbrukning kan det vara lönsamt att samtidigt energieffektivisera byggnaderna, bland annat genom tilläggsisolering. Det är av stor vikt att noggrant undersöka hur byggnaderna påverkas ur fukthänsyn innan nya fasadsystem tas i bruk för att undvika framtida fuktrelaterade skador.Syftet är att undersöka tre fasadsystem utifrån hur olika fuktbelastningar, väderstreck, tilläggsisoleringar och stommaterial påverkar ytterväggars fukttillstånd och risken för mikrobiell tillväxt. Även hur väl de olika fasadsystemen lämpar sig för att uppföras på en befintlig stomme i trä-, lättbetong- och betongstomme har undersökts. För att undersöka detta har fuktsimuleringar gjorts i fuktberäkningsprogrammet Wufi och resultaten har analyserats genom jämförelse av RF-kurvor samt riskbedömning för mögeltillväxt i Wufi Bio.En övergripande slutsats är bland annat att inläckage av slagregn är en stor belastning för fasadsystemen. Systemens fuktsäkerhet beror till stor del på dess förmåga att hantera inläckaget.Studien visar även att en fungerande ventilerad luftspalt, en god dränerande funktion eller en konstruktion med genomgående relativt ångöppna material har förmågan att hantera inläckage av slagregn effektivt. / A large number of buildings built under “miljonprogrammet” is today in need of renovation. With their high energy consumption it is also considered profitable to improve the buildings energy efficiency e.g. by additional insulation. It is however important to thoroughly evaluate potential damp issues that might arise as a result of these improvements before starting to implement a new building exterior.The aim of this study was to investigate three different façade systems based on how their moisture content and risk for mould growth are affected by different moisture loads, orientation, and additional insulation. Included is also a performance evaluation for each building exterior solution mounted on existing structure of wood, lightweight concrete and concrete structure. Damp simulations were done with the program Wufi and the results were then analysed by comparison to RF-curves in combination with risk assessments of the growth of mould with “Wufi Bio”.The overall conclusion shows that leakage due to torrential rain poses a great strain on building exterior systems. A solutions damp proof quality is largely dependent on its ability to withstand leakage from outer sources.The study also shows that a well ventilated cavity wall, sufficient drainage or a construction of exclusively vapour open materials has a positive impact on the amount of leakage.

This report is written for the construction company NCC and Uppsala University, with the goal to investigate if there is a simple method to compare building materials from the perspective of sustainability, to help the decision-making when choosing materials for building Projects. To test the method four facade systems (brick, ventilated plaster, unventilated plaster and cement board) have been analyzed with different tools used for sustainable assessement, namely: Life-cycle cost analysis, Life-cycle analysis and assessment criteria. To make a final assessment of the four facade systems and combine the results of the above mentioned tools, a multiple-criteria decision analysis was used. The result from the final assessment show that unventilated plaster facade is the most sustainable option, when analyzed from an assumed lifespan of 50 years. The results, however, are seen as questionable due to the fact that the criteriums and their weight to the final results are based on this report's author's estimation and may not represent an objective truth. Due to the lack of available data, many assumptions were required when utilizing the tools, which further diminished the credibility of the results. The conclusion is that there is no simple method to compare the sustainability of building materials that captures the entire spectrum of what sustainability consists of. Instead of trying to find a new method, the already established enviromental certificates should be used and further developed.