Lucas123 writes: A company in China has used additive manufacturing to print 10 single-room buildings out of recycled construction materials in under a day as offices for a Shanghai industrial park. The cost: about $5,000 each. The company, Suzhou-based Yingchuang New Materials, used four massive 3D printers supplied by the WinSun Decoration Design Engineering Co. Each printer is 20 feet tall, 33 feet wide and 132 feet long. Like their desktop counterparts, the construction-grade 3D printers use fused deposition modeling (FDM), where instead of thermoplastics layer after layer of cement is deposited atop one another. The cement contains hardeners that make each layer firm enough for the next. Yingchuang's technique builds structures off site in a factory one wall at a time. The structures are then assembled onsite. The technique is unlike U.S.-based Contour Crafting, a company whose 3D printing technology to form the entire outer structure of buildings at once, The Yingchuang factory and research center, a 33,000 square foot building, was also constructed using the 3D printing manufacturing technique. It only took one month to construct.