American Panel Corporation was established in Miami, Florida in January of 1963 with four employees and 5,000 square feet of building space. Marvin L. Duncan, the company's founder and CEO, originally set out to develop and manufacture prefabricated homes constructed with insulated building panels. The unique building panels were made of prepainted metal skins bonded to both sides of an insulating core material. It was soon discovered that walk-in coolers and freezers could be manufactured using similar materials and construction techniques and that their quality and versatility rivaled or exceeded any product already on the market. In 1965, full attention was turned to the prefabrication of coolers and freezers, with a subsidiary being formed to manufacture reliable, high quality refrigeration systems that complemented the walk-ins.
As the business grew, so did the need for larger facilities. By the late 70's, despite the fact that the company had grown to occupy 55,000 square feet of office and manufacturing space, additional expansion was necessary, and in April of 1983, the entire operation was relocated to Ocala, Florida, where a new 65,000 square foot facility was custom built on 15 acres of property. By 1998, a need for further growth of the Ocala facility was identified and an aggressive expansion project begun.