Most large production builders today use what is called partial prefabrication. The walls of this house, for example, arrive from the factory as large panels. The panels are not dimensionally standardized, although repetition is used when possible. (Note that this steep-roofed house uses the same end-wall panel as a low-slope model, but surmounted by an insert.) Panelized houses can be erected more quickly than conventional stick-built versions, and since everything is precut, there is less waste; perhaps even more important, maximizing factory work allows the builder to effectively control the quality of the workmanship and materials. Not as neat as a bolted-together Eiffel building, but suited to American construction techniques.