TechniquesOslo (proposal) Helsinki GteborgPublic AreasLobby, foyers, halls sq.m. 4,800 5,650 4,370Production AreasMain stage + stage areas sq.m. 2,250 2,180 1,880Additional stages sq.m. 550 600 300Rehearsal rooms sq.m. 2,700 2,320 2,590Dressing rooms artists sq.m. 1,700 1,560 1,060Dressing rooms staff sq.m. 300 440 345Staff room sq.m. 900 1,260 1,030Management/administration sq.m. 1,300 1,500 715Workshops sq.m. 2,800 2,500 3,060Storage sq.m. 4,000 6,250 2,440Other areas sq.m. 700 300 1,800Technical areas sq.m. 300Ballet school sq.m. 600 620 Net area sq.m. 22,900 25,180 19,590Gross area sq.m. 35,500 40,300 30,326Example: an opera benchmarkBenchmarking is frequently used for common building types, such as office buildings, but it can be just as useful for special building types, such as opera buildingsalthough the data will be less easy to find. This example is a benchmark that was used in the briefing process for the new opera house in Oslo. The basic question was whether 35,500 sq.m. was a reasonable size for such a project. 98