A method for preparing a monolithic nanoporous silicate sol-gel material for modulating the pore size distribution for one single starting composition without the addition of a structuring agent. The method includes the following steps: a) synthesising a gel from at least one organosilylated precursor, the synthesis being carried out in an aqueous medium, optionally including an organic solvent and without a structuring agent, and b) drying the gel obtained in step a) at a temperature between 10° C. and 70° C., preferably between 15° C. and 55° C. and more preferably between 20° C. and 40° C., in a gas flow in a drying chamber to obtain a monolithic nanoporous silicate sol-gel material and a residual relative humidity in the drying chamber of between 0.1 and 20%, preferably between 0.5 and 10% and more preferably about 5%.