A process for manufacturing an inorganic foam includes (i) separately preparing an aqueous foam and a cement slurry, the cement slurry including water W, a cement C, a water-reducing agent, a water-soluble calcium salt, a water-soluble silicate salt, the calcium/silicon molar ratio being 0.7 to 1.7 and the W/C weight ratio being 0.25 to 0.40, and given that the calcium ion concentration is 0.03 to 0.97%, expressed as weight percent relative to the weight of the cement, and that the silicate ion concentration is 0.04 to 1.67%, expressed as weight percent relative to the weight of the cement; (ii) contacting the cement slurry obtained with the aqueous foam to obtain a foamed cement slurry; and (iii) shaping the foamed cement slurry obtained in step (ii) and allowing setting to occur.