Completed in September of 1935, the Windowless Office Building provided a tightly controlled environment for employees. It featured central air conditioning, “scientifically” planned artificial lighting, glass partitions in place of walls, and outdoor scenes painted on walls in place of windows. Described on postcards of the time as “Science’s latest work to aid workers at Hershey”. The art-deco exterior is made of local limestone accented with Indiana Limestone and granite trim. The roof is perfectly level and designed to hold 2 ½ inches of water. This method of holding water on the roof is intended to help insulate the building in both summer and winter. The large towers placed along the building façade are not mere decoration but are also part of the air-conditioning and ventilation system.