The first part of the paper refers to the history, division and mode of operation of the boiler plant, where the importance of the turbine and generator in the plant itself is emphasized, since they are the main parts of the boiler. In order to be able to build a boiler, it is necessary to know steels and their properties. This paper describes the steels that are most often used and for which parts of the boiler, ie the construction of the membrane wall, because the term boiler is much larger than the membrane wall itself. In addition to the description of steels, the method of dimensioning or selection of materials of pipes, strips and other necessary parts for the production of a membrane wall is described. The main part of the paper is related to the construction of the membrane wall. The paper describes the manufacturing steps, so the first step is to weld the panels. This welding is performed by powder arc welding (EPP). This is followed by welding of the butt joints by non-melting electrode (TIG) arc welding. At the end of production, electric arc welding in gas protection (MIG / MAG) is applied for welding non-pressure parts such as boxes, fish, various sheets for connection with other membrane walls. After the welding is completed, the inspection follows. Control consists first of visual control. This method is also performed before and during welding. It determines that all positions have been set and that they are welded. Then, depending on the welding plan, penetration and magnetic controls are performed. The butt joints are examined by radiography as one of the volume methods. Once an acceptable control has been established, the membrane wall is ready and prepared for transport.