The issue of global warming and untenable energy production is beginning to receive more attention around the globe. One area of the problem is the industry of buildings and the construction of materials which leads to CO2 emissions. The objective with this project is to investigate the smart climate buildings which the construction company ETC is now building in Västerås and Växjö. The idea and principle of their buildings is to mainly focus on wood as the main building material which leads to less environmental emissions. This project will investigate the benefits with massive wood as building material and work within the programs IDA ICE and PVGIS to simulate the electricity production from PV-systems and the energy values of the building both in Västerås and Växjö. To gather intel and information about the subject in the project a case study is carried out where previous studies are presented. The first results shows that the simulated building in IDA ICE presents a lighter building than the original ETC building and therefore a higher energy consumption which should be accurate according to earlier studies. Furthermore, these results shows that the assumptions that has been made in the different software’s could have an overall high effect on the result. This project and it´s simulations have declared a positive effect by using wood as the overall material in the building. Earlier studies show that other materials as concrete and stone present a more thermal inertia in the building which contains the heat better than lighter buildings made of wood. But after all, this project shows that with using wood within different layers a more sustainable climate shell is presented and contributes to a lower energy need. Further on, Research on the subject in the future should consider more details about the choice of materials and input in the programs to get a more accurate result. These details could not be considered in this project due to flaws in the material database.