The study considers solutions and systems for temporary and prefabricated constructions developed in Italy in the 1930s and 1940s. Companies such as L’Invulnerabile, Curtisa, Legnami Pasotti, Giuseppe Palini e Figli, Fratelli Ravelli proposed easy to assemble, changeable, and in many cases, dismountable buildings destined to the 1930s Italian and colonial markets. The survey aims to reconstruct different cases, highlighting both the premises that determined the vanguard of the post-war debate on building industrialization and the factors that constrained further developments of the pioneering phase analysed. The study starts with the V Triennale of Milan (1933) and develops in the colonial season in East Africa, enriched with applications in the Alpine areas, before finally considering some proposals that were presented at the Consiglio Nazionale delle Ricerche exhibition on prefabricated houses in 1945 and the development of some patents by manufacturers specialised in this building sector. The buildings were intended for houses and offices of the Istituto Nazionale delle Assicurazioni and the Azienda Mineraria Africa Orientale in the colonial areas, for bivouacs of the Club Alpino Italiano, and for prefabricated houses advanced in the Second post-World War period by Società Anonima Legnami Pasotti and by L’Invulnerabile. The study, based on the clients’ archives (Istituto Nazionale delle Assicurazioni, Azienda Mineraria Africa Orientale, Club Alpino Italiano), technical documentation, and patents of the manufacturing companies, favours the examination of the production and assembly process.