Hidden Innovation and Italian Architecture of the Twentieth Century. Component of Light Technology in the Church of Cristo Re in L’Aquila

When in 1933, the architect Riccoboni, Superintendent of Medieval and Modern Art for Abruzzi and Molise regions, drew up the plans for the Church of Cristo Re in L’Aquila, the reinforced-concrete framework had, in Italy, already fulfilled completely its function as an independent load-bearing building skeleton. It does not appear that Riccoboni had gone into the technological aspects in depth. In the choice of a construction system for the church, the decisive contribution came from engineer Vacca, the designated agent of the ACEAM firm which won the contract for the work. He offered a 30% discount on the cost of the project if he could be allowed to use the Hestia building system instead of ordinary masonry. This system consisted in filling the vertical meshes of the reinforced-concrete frame using paired panels of expanded metal covered with concrete-based plaster, with the air space between the panels being filled with an insulating material made of cellulose, quicklime and gypsum called Termolit. The load-bearing skeleton was a frame made of reinforced-concrete portals forming a nave and two side aisles, connected by beams on the level of the floor and of the two eaves of the aisles and of the nave; it rested on a continuous foundation of concrete mixed using coarse gravel and a low percentage of cement. Analysis of the direct source, represented by the open building site, delved more deeply into and confirmed the indirect archival and bibliographical sources of the time, and revealed the characteristics of the structure, the walling, and the adoption of a system of arched wooden structures cladding using plastered metal mesh, hung from the load-bearing skeleton, which configures the interior space by means of the transversal and longitudinal arches of the naves.