A customizable closure system comprising panels of a pre-selected size and one or more conversion kits for mounting the panels. A room divider conversion kit comprises a hinge for converting the panels into room dividers, and a bypass conversion kit comprises a header for converting the panels into slidable panel doors, such as a closure for a shower area. Other conversion kits include a swing conversion kit and a hanger conversion kit. One embodiment of the panels further comprises a reinforcing system for securely retaining the panes with the panel.