A stud for enabling a construction surface to be raised with respect to the ground, said stud comprising at least a first and second element, said first element comprising a first body mounted on a base intended to be placed on said ground, said second element comprising a second body, each of the bodies being provided with a screw thread for mutually engaging one in the other, thus forming an internal body and an external body, said external body being provided with an orifice giving access to the screw thread of the internal body, said stud also comprising a locking member arranged to lock the movement of the first body with respect to the second body in a plurality of positions, the locking member comprising first and second segments, said first segment being designed to pass through said orifice and be inserted between two successive grooves of the screw thread on the internal body, said second segment being designed to pass through said orifice and be interposed in a space provided in an internal wall of the external body.