Abstract: A method of lining the hot face of the wall of a heated enclosure, such as a furnace, boiler or the like, comprising the steps of compressing a plurality of substantially cylindrical modules of ceramic fiber material inwardly from the perimeter thereof; attaching the individual, compressed modules to the hot face of the wall in predetermined relationship whereby to define certain openings therebetween, inspecting the attaching means by virtue of the access thereto provided by the openings; filling the openings with a plug of ceramic fiber material; and then releasing the compression upon the modules to permit radial expansion thereof in all directions whereby to create a lining over the entire wall.