Hårdare energidirektiv från EU gällande energianvändning i byggnader har resulterat i Boverkets framtagande av Sveriges kommande nära-nollenergilagstiftning. Den kommande lagstiftningen kommer ur energisynpunkt innebära ett paradigmskifte för hur man projekterar och bygger nya byggnader i Sverige. I samarbete med WSP Sverige AB har detta arbete huvudsakligen undersökt potentialen att klara av denna omställning, genom att fokusera på minimering av energiförluster från transmission i en byggnads klimatskal. Arbetet innehåller en omprojektering av en specifik byggnads klimatskal. Vid framtagandet av detta klimatskal har olika konstruktionsalternativ simulerats och analyserats för att på ett kostnadseffektivt sätt avgöra den ambitionsnivå som krävs för att uppnå kraven i den kommande lagstiftningen. Utöver Boverkets kommande lagstiftning har även möjligheten att klara av viktade krav från miljöclassifieringssystemet Miljöbyggnad analyserats.

Increasing the energy efficiency of buildings and the introduction of more strict regulations are small but important steps towards a better climate. Today the housing and services sector stands for nearly 40 % of Sweden’s energy use. To push the development towards more energy efficient buildings in Europe, all the new buildings are required to be nearly zero-energy buildings by 2021. The purpose of this project was to evaluate whether the use of an additional facade board on an apartment building results in putting the energy performance within the current energy performance requirements, and also within the future requirements for nearly zero-energy buildings (NZEBs). The facade boards that were tested in this project are manufactured by Kingspan and Isover. The different boards were tested in thicknesses of 30 and 50 mm. The aim of the project was to calculate the building’s average heat transfer coefficient, specific energy use and primary energy number (PET) using COMSOL Multiphysics (CM) and IDA Indoor Climate and Energy (IDA ICE). The results were then about to be controlled against the current energy performance requirements together with the future requirements for NZEBs. The approach of this project consisted of the use of the softwares CM and IDA ICE. Because IDA ICE requires input of the thermal bridges of the building, CM was used to simulate these. This was done in order to achieve more reliable values than if an assumption was made or a standard value was used. A model of the building was then created in IDA ICE where its energy performance and average heat transfer coefficient were obtained from simulations over a normal year. The results obtained from the simulations in CM seemed credible as the use of the best facade board caused the values of the thermal bridges to end up at ”Good” according to IDA ICE’s built in scale. The simulations in IDA ICE showed that the specific energy use of the bulding without an additional facade board was 55,9 kWh/m2,year compared to Boverket’s current requirements at 80 kWh/m2,year. With the 50 mm Kingspan facade board, the board with the best result, the specific energy use was reduced to 53 kWh/m2,year, an improvement of 5,2 %. For the case without an additional facade board, the PET was 66,6 kWh/m2,year compared to the NZEBs requirements for 2018 at 85 kWh/m2,year together with the requirements for year 2021 at 65 kWh/m2,year. By using the 50 mm Kingspan facade board the PET was reduced to 63,3 kWh/m2,year, an improvement of 5,0 %. This resulted in putting the PET below the NZEB requirements for 2021. The facade board that resulted in the least energy savings, Isover P31 30 mm, had an improvement of 2,5 and 2,7 % for the specific energy use and the PET respectively. This facade board also resulted in putting the PET below the NZEB requirements for 2021. The most obvious conclusions that could be drawn from the simulations was that the specific energy use was below the current energy performance requirements with a great margin, both with and without an additional facadeboard. The PET was well below theNZEB requirements for 2018 and was also belowthe NZEB requirements for 2021 using any of the tested facade boards. The building’s average heat transfer coefficient was also well below both today’s energy performance requirements and the NZEB requirements for 2018 and 2021. A use of an additional facade board resulted in an energy saving of around 2,5 and 5 % in the worst and the best case, respectively. Due to the neglect of the ring wall under the bulding, the energy performance is most probably slightly high. However, this is not of utmost relevance since the company normally does not use this kind of solution for their standard buildings. Other uncertainties about the choice of airflows in property spaces may have influenced the results in the other direction. If there are any other obvious energy saving measures than using an additional facade board, these should be taken into account primarily as a facade board can only reduce the energy use marginally.

Purpose: Production and utilization of buildings contributes immensely to global carbon dioxide emissions. The construction sector today accounts for over a third of global energy use will increase as the world population increases. According to the EU Directive from 2010, all new buildings in EU member countries as of December 31, 2020 are to be classified as near-zero energy buildings (NZEB). The goal is to investigate the various energy-affecting measures of the involved architects, structural engineers and planners that can improve the energy performance of a kindergarten to be closer to near-zero and identify obstacles that make it more difficult to achieve NZEB. Method: The investigation strategies for the project are qualitative methods in the form of semi-structured interviews with architects, planners and ventilation engineers for six different kindergartens. The interviews were conducted by telephone in which the questions were sent in advance to those interviewed. Mail interviews were conducted early on which resulted in either short answers or not answers at all. The energy performance documents of the different kindergartens were analyzed to get information about the different energy performances. Findings: The result does not contain a solution as to what the near-zero energy definition is or how to define it, but is more like guidance concerning what factors you can influence to get closer to near-zero energy for a kindergarten. Recurring problems surfacing in the interviews is that not all the involved roles have been able to influence predetermined choices of shape and space that, among other things, contribute to a limited space for services that planners are having difficulty influencing afterwards. Implications: The result helps contribute to making sure buildings are built in a more energy-efficient way and by such reducing the construction sector's share of the global energy consumption. The building's energy efficiency may not contribute to poor indoor climate in such a way that it affects children's health in a negative manner. This results in a need for careful planning where all parties can contribute with their best energy efficiency solutions without being too limited by the architectural constraints of shape and space. Alternatively, better communication between planners and architects in the earlier stages. Good planning contributes to a better result. Limitations: The result is based on Swedish kindergartens in a Nordic climate and should not be applied in countries without a Nordic climate. The result is not only applicable to kindergartens but is largely applicable to most similar buildings. Contact with more architects, constructional engineers, planners and more kindergartens would have given a better result.

With the EU's introduction of Near-zero energy requirements to be implemented in all member states by 2021, the construction sector faces a challenge in which all new building constructions are receiving tightened demands for energy conservation. In the latest edition of Boverkets Byggregler, Boverket, the Swedish National Board of Housing, has revised the energy conservation section as the first of two steps in the introduction of the Near-zero energy requirement in Sweden, where the method of calculating energy consumption is renewed and primary energy aspects are now being considered.   As it is not yet completed what the exact level of requirement for Near-zero energy is, this study applies the proposal for Swedish application of Near-zero energy requirements published by Boverket in 2015, which proposes, among other things, which primary energy factors to use for different energy carriers and use this in combination with the new method of calculating energy consumption according to the latest edition of Boverkets Byggregler.   In addition to investigating what Near-zero energy will mean, the study had as its main objective to investigate what measures can be taken to the model house, provided by Nordisk Boutveckling, to enable the building to meet the new requirements. The study was therefore designed as a parameter study, where various measures to improve the building's energy conservation were tested in the energy-calculation program VIP-Energy.   The result shows that the building, which is considered to be of a typical construction standard, is able to meet the requirement when it combines existing solar cells on the roof with a battery that can store the energy produced during the solar hours and then use this to provide the building with electricity for heating, real estate energy and for the production of tap water instead of allowing the electricity to be sold or used as household-electricity. The result also shows that installing better windows is an effective measure if the building is to meet the energy requirements with a certain margin of safety. It also turns out possible to meet the requirements by improving the building with a number of measures and using district heating as a heating method.