Stretching tensioner for tensioning a guide wire comprising: a tensioner base attachable to a lift platform and having a first opening, a housing located on a bottom side of the tensioner base for housing the guide wire, and a wire lock clamped on the guide wire underneath the housing and fixing the guide wire with respect to a base of the housing, characterized in that the housing comprises: a hollow threaded shaft that extends through the first opening from a top side of the tensioner base to the bottom side of the tensioner base, the hollow threaded shaft having an external thread and an internal through hole for the guide wire, an activation nut located on the top side of the tensioner base, and rotatably fixed to the hollow threaded shaft, a bearing between the hollow threaded shaft and the bottom side of the tensioner base for allowing rotation of the hollow threaded shaft with respect to the tensioner base, a tensioning nut with a thread mating with the external thread of the hollow threaded shaft, wherein the tensioning nut is axially displaceable within the housing but rotatably fixed to the housing, a resilient element arranged between the tensioning nut and the base of the housing such that upon rotation of the activation nut the tensioning nut moves axially to compress the resilient element. a tensioner base attachable to a lift platform and having a first opening, a housing located on a bottom side of the tensioner base for housing the guide wire, and a wire lock clamped on the guide wire underneath the housing and fixing the guide wire with respect to a base of the housing, characterized in that the housing comprises: a hollow threaded shaft that extends through the first opening from a top side of the tensioner base to the bottom side of the tensioner base, the hollow threaded shaft having an external thread and an internal through hole for the guide wire, an activation nut located on the top side of the tensioner base, and rotatably fixed to the hollow threaded shaft, a bearing between the hollow threaded shaft and the bottom side of the tensioner base for allowing rotation of the hollow threaded shaft with respect to the tensioner base, a tensioning nut with a thread mating with the external thread of the hollow threaded shaft, wherein the tensioning nut is axially displaceable within the housing but rotatably fixed to the housing, a resilient element arranged between the tensioning nut and the base of the housing such that upon rotation of the activation nut the tensioning nut moves axially to compress the resilient element. a hollow threaded shaft that extends through the first opening from a top side of the tensioner base to the bottom side of the tensioner base, the hollow threaded shaft having an external thread and an internal through hole for the guide wire, an activation nut located on the top side of the tensioner base, and rotatably fixed to the hollow threaded shaft, a bearing between the hollow threaded shaft and the bottom side of the tensioner base for allowing rotation of the hollow threaded shaft with respect to the tensioner base, a tensioning nut with a thread mating with the external thread of the hollow threaded shaft, wherein the tensioning nut is axially displaceable within the housing but rotatably fixed to the housing, a resilient element arranged between the tensioning nut and the base of the housing such that upon rotation of the activation nut the tensioning nut moves axially to compress the resilient element.