The stadium has a retractable roof, built in a unique fan-shaped style, with the roof panels opening and closing simultaneously in a sweeping manner from the first- and third-base sides toward center field. The complex and massive roof was a significant factor in the $392 million cost of the stadium. It allows the seating area to be heated warmer than the outside temperature when closed, allowing games to be played in inclement weather and in more comfortable conditions than an open-air stadium. For example, when it is freezing outside, the temperature inside will be . The idea of the stadium having a retractable roof had been considered right away in the initial design, as to help counter the unpredictable Wisconsin weather in the early spring and late autumn.