A computer-implemented automated building mechanical systems design and modeling is described. The system provides a central source for all of the design and construction information for systems in a construction project in a coordinated two-dimensional and three-dimensional spatial database that is accessible as a means to produce automatically coordinated design development and construction document information of the mechanical systems. The system acquires and stores all of the appropriate design, engineering, and construction expertise information available for any building type for use in automatically assembling and coordinating the design, cost-estimating, and scheduling for the mechanical systems of the construction project. The system output model enables automatic generation of drawings and cost, manufacturing and scheduling information.

A screen creation device, which supports the creation of a user interface screen for a numerical controller, is provided with a part library that stores parts to be placed on the user interface screen and composite parts that are combinations of a plurality of parts. The screen creation device: acquires mechanical information about a machine tool to be controlled by the numerical controller; determines composite parts that can be used on the user interface screen based on the mechanical information about the machine tool; presents the usable composite parts to a user; and accepts the placement of the usable composite parts onto the user interface screen.