Abstract: A kit, which is particularly intended for the fireproof laying of cables and ducts, has endwise connectable, self-supporting components made from thermally insulating material and substantially elongated metal reinforcements. The self-supporting components are duct sections (4 to 12), which in each case comprise a trough section (4' to 12') made from thermally insulating material and externally reinforced by longitudinally continuous sheet metal parts (16) and which has a substantially U-shaped cross-section, and a cover (4" to 12") also made from a thermally insulating material. The trough sections (4' to 12') being in each case equipped for the cover-less laying of the duct (1), are connectable with adjacent trough sections (4' to 12'); and the associated covers (4" to 12") are detachably fixable.