WEST TOWER FACADE RESTORATION: FIRST NATIONAL BANK BUILDING

摘要

The West Tower of the First National Bank Building in St. Paul, MN, is an iconic building on the St. Paul skyline (Fig. 1). Built in 1931, the building is best known for the neon red "1st" sign that can be seen as far as 20 miles (32.2 km) away on a clear day. The tower was the tallest building in St. Paul for nearly six decades (1930 to 1986). The 32-story tower rises 402 ft (122.5 m) above the surrounding sidewalk, with the support structure for the iconic "1st" sign rising an additional 100 ft (30.5 m). The Art Deco style of the building is similar to the Empire State Building in New York City. Both of these buildings were built at the same time and competed for many of the same building materials. The main building facade consists of Indiana limestone. The tower, being located in Minnesota, is exposed to one of the widest ranges of weather events in the country. With an average of 143.5 days below freezing and temperatures that reach above 100℉ (38℃) in the summers, the building's facade experiences numerous freeze-thaw cycles annually.