Abstract: A method for producing a hollow body that is pressure-tight for a predetermined medium through the joining of at least two sub-bodies, which when joined form the hollow body that contains the medium in a gaseous and/or liquid state during the intended use of the hollow body; the at least two sub-bodies are integrally joined by means of an integral joining method that can be successfully performed at ambient pressure; the medium is introduced into at least one sub-cavity of at least one sub-body in a solid or partially solid state before the integral joining is performed, the medium is introduced together with a container element that contains or holds the medium in a solid or partially solid state, from which containing element the medium can escape in the liquid or gaseous state; and then the integral joining is carried out.