What is Jamming?

Definition of Jamming in Construction
The occurrence of a misalignment that causes a functioning element in a door or window, to stop working due to excessive friction, or the inability to slide, swing, tilt or function. The term jamming in construction is a very universal description of a difficult functioning element. To jam up is a descriptive term that references the commencement of the movement and a stoppage of this movement partially through the cycle. A double hung window that has a window sash jam up is a situation where the window sash was partially lifted and normally in a sudden manner, the window stopped moving and jammed up in the actual frame of the window. A common reason that a sash or a window or door will jamb up, is the inaccurate installation of the window or door. The alignment of the element within the frame is not accurate and therefore upon activation, the element simply either racks and twists or just stops working due to friction build up.