In this work, we have investigated in detail how the hydration thermodynamics and electrolyte intrusion in silicalite-1 and chabazite zeolites is affected by introducing various amount of attractive point defects (modeled by silanol nests) into the parent pure-silica zeolites. First, we reproduced qualitatively the evolution of hydration as a function of the strenght of silanol defects introduced in the zeolites. In presence of "weak" defects, the adsorption isotherms for both chabazite and silicalite-1 are of type V (according to IUPAC classification). The effect of weak defects is to make the framework more attractive as shown by a slight shift of the condensation transition, although the frameworks remain hydrophobic. As for defect-free zeolites, the condensation transition occurs through a homogeneous nucleation process. In case of "strong" defects, the isotherms shift to type IV. The first stage of water loading is attributed to a heterogeneous nucleation of water around the defects, forming small water clusters. The next stage consists of the growth of these clusters of water acting as a seed to trigger condensation transition.