Method for producing reduced-weight plasterboards

Process for the manufacture of plasterboards exhibiting a core density of less than 0.77 comprising the stages of the formation of a foam from water and a surfactant composed of at least one alkyl sulphate of formula H(CH 2 ) n OSO 3 − M + , in which n is a number between 6 and 16, M is a monovalent cation and the mean number of carbon atoms n m is from 9 to 10, and the introduction of the foam obtained into a plaster slurry, characterized in that the amount of surfactant introduced does not exceed 0.32 g/l of plaster slurry. Application to the manufacture of lightened plasterboards.