Sight lines can be improved by elevating the focal point and creating elevation change between rows. The use of a radius layout also helps to improve sight lines. Irwin Seating Company can provide a study showing sightline clearances. Of course, this data is only relevant in the preliminary stages of design. Once the concrete is poured the mold is cast and sight lines cannot be improved easily.
Above is an example of a sightline study that shows clearances for each of the rows, or selected rows, in the auditorium. The angular differences from row-to-row provide excellent sightline clearance near the front of the auditorium. In the rear of the auditorium, it is necessary to increase elevation at a greater rate than in the front of the room.