Prior to 1902, the tallest reinforced concrete structure in the world was only six stories high. Since concrete possesses very low tensile strength, many people from both the public and the engineering community believed that a concrete tower as tall as the plan for the Ingalls Building would collapse under wind loads or even its own weight. When the building was completed and the supports removed, one reporter allegedly stayed awake through the night in order to be the first to report on the building's demise. Ingalls and engineer Henry N. Hooper were convinced, however, that Ernest L. Ransome's system of casting twisted steel bars inside of concrete slabs as reinforcement and casting slab, beams and joists as a unit would allow them to create a rigid structure. The architects also prized the cost savings and fireproofing advantages of concrete over steelframe construction. Finally, after two years of convincing, city officials issued Ingalls a building permit and the work began.
Construction
Hooper designed a monolithic "concrete box of eight-inch walls, with concrete floors and roof, concrete beams, concrete columns, concrete stairs -- no steel. It consists merely of bars embedded in concrete, with the ends interlaced." The amount of concrete produced during construction—100 cubic yards in each ten-hour shift—was limited by the rate at which the builders could place it. An extra wet mix was used to ensure complete contact with the rebars and uniform density in the columns. Floor slabs were poured without joints at the rate of three stories per month. Columns measured 30 by 34 inches for the first ten floors and 12 inches square for the rest. Three sets of forms were used, rotating from the bottom to the top of the building when the concrete had cured. Completed in eight months, the finished building measures 50 by 100 feet at its base and 210 feet tall. The exterior concrete walls are eight inches thick in unbroken slabs 16 feet square with a veneer 4 to 6 inches thick. The Beaux Arts Classical exterior is covered on the first three stories with white marble, on the next eleven stories with glazed gray brick, and on the top floor and cornice with glazed white terra cotta.
The building was purchased on January 17, 2013 by CLA OH LLC from CapCar Realty 1.1 LLC, for $1.45 million. In November 2013, Claremont Group CEO Perry Chopra disclosed his intentions to convert the office building into 40 to 50 condos, with ground-floor retail. However, in April 2015, a real estate broker announced that the building was again for sale, after Claremont Group decided not to execute the condominium project.
