Crosslinkable compositions based on organosilicon compounds, more particularly RTV-1 sealants, contain (A) at least one organosilicon compound having at least two condensable radicals, (B) at least one finely divided silicon dioxide having a BET surface area of 30 to 120 m2/g and a relative thickening effect ηrel of 1.4 to 10, and (C) at least one hydrocarbon component which has an initial boiling point above 150° C., a final boiling point below 350° C., each at a pressure of 1013 hPa, a kinematic viscosity of 1.5 to 6.0 mm2/s as measured at 40° C., a viscosity-density constant (VDC) of less than or equal to 0.820, a pour point of less than −5° C., and an aromatic carbon atom (CA) content of less than 0.1% CA.