The world is due to the large amounts of greenhouse gases emissions facing climate changes. These emissions are increased also by civil engineering and by building facilities, apartment buildings having the largest share in it. To alleviate climate changes as well as the amount of CO2 emissions, these emissions have to be decreased, or CO2 has to be removed and stored. The only currently known material which has the power to do both is wood. For my bachelor's degree thesis I will, therefore, look into the Slovenian systems of wood constructions and present them. From the building contractors, I will choose two constructional complexes of the outer wall from each of the wood building systems. One of them will have wood only for load-bearing construction, the other one also for thermal and hydro insulation. The analysis of constructional complexes will be done in TEDI program. The results of building-physics qualities will be compared to the Slovenian conventionally built constructional complexes of the outer wall. With the help of already-existing studies I will evaluate some constructional complexes from the point of view of environmental parameters. I will also give a comparison between these results and the conventional building in Slovenia. I intend to show how using wood in building facilities can help reduce the amount of releasing CO2 emissions in the atmosphere, as opposed to a masonry building. A building made of wood also has better buildingphysics qualities. I wish to accomplish that the number of these buildings in Slovenia would rise.