Humidity, particularly rising damp, is one of the main causes of degradation of historical constructions. This type of humidity manifestation appears when the constituent materials of the walls exhibit high capillarity and these walls are in contact with water or wet soil. The treatment of rising damp in historical buildings walls is very complex. Moisture transfer in walls of old buildings, which are in direct contact with the ground, leads to a migration of soluble salts responsible for many building pathologies. In this work a sensibility study was done, using an automatic calculation program, WUFI 2D v.3.3, with the main goal to determinate the influence of some variables in the capillarity rise of different monolithic walls, namely the importance of material properties (as porosity), exterior climate and wall thickness.