Cemesto is a sturdy, light-weight, waterproof and fire-resistant composite building material made from a core of sugar cane fiber insulating board surfaced on both sides with asbestos and cement. Its name is a portmanteau word combining "cem" from "cement" and "esto" from "asbestos." A type of prefabricated home using this material came to be called cemestos. Cemesto was introduced by the Celotex Corporation in 1937. It was manufactured in the form of boards and panels that were wide, about thick, and to long. Each by panel weighs just . Cemesto was used primarily for interior and exterior walls. The John B. Pierce Foundation and Celotex collaborated to develop a prefabrication system for building low-cost housing using cemesto panels, in which single cemesto panels were slid horizontally into light wooden frames to create walls. A prototype cemesto house was displayed at the 1939 World's Fair in New York City. The Pierce system was first used in 1941 for building employee housing at the Glenn L. Martin Aircraft Company near Baltimore, Maryland. For this development, named Aero Acres, the architecture firm of Skidmore, Owings & Merrill designed gable-roofed Cape Cod houses with dimensions of by , featuring large commercial-style windows in their principal rooms. In 1941 a total of 600 homes were built at Aero Acres using this design. During World War II, when other building materials were in short supply, cemesto was used extensively in the United States. Cemesto was used to build temporary office buildings in Washington, D.C. Skidmore, Owings, and Merrill adapted the Pierce system and used cemesto panels for the designs of some 2,500 pre-fabricated homes, known by the nickname "cemestos," erected in Oak Ridge, Tennessee, to house Manhattan Project workers and their families. In 1942 the U.S. Farm Security Administration built 400 cemesto homes in Maryland at a site alongside Aero Acres. During the 1940s, the manufacturer of cemesto touted it as a material that would in the future make it possible to mass-produce housing at a low cost. One use of the material during the post-war era was in the late 1940s in Circle Pines, Minnesota, where cemesto panels were used in building the first homes in what was envisioned to be a cooperative housing community for people of color. The use of cemesto in Circle Pines came to be regarded as substandard construction, as the builders failed to adequately seal the joints between cemesto panels.