Abstract: During the assembly of a steam generator, the boiler columns are assembled, and, in parallel, headers and other wall boxes are assembled on booms of the boiler columns, so that when the boiler columns are completed, the headers and wall boxes are also finally assembled. Next, the peripheral roof section is assembled onto the boiler columns, and the vertical steam generator-containing walls are suspended from the peripheral roof section. Parallel to this, the inner roof section is constructed and the convection heating surfaces are successively mounted to the inner roof section and lifted upward from the base. The assembled inner roof section and convection heating surfaces are then lifted to the height of the peripheral roof section, and the two parts of the roof are connected. Finally, the furnace walls having a vertical or inclined tube arrangement, including the furnace hopper, are assembled.