The retail giant has worked with contractors utilizing 3D-printed construction for store walls in Tennessee, Arkansas, Alabama, and Missouri over the past several years. Contractor FMGI, which has partnered with Walmart on these projects, reports that using robots to print walls reduces construction costs by 15% and cuts production times by 33%. For 30 years, I’ve watched the construction industry just do it the same way over and over. FMGI relies on 3D printers manufactured by Alquist, which build walls by spreading successive layers of a concrete composite material on top of each other. The printing process does come with operational constraints, as the machinery requires fine-tuning, cannot function in severe winds, and needs the concrete mix maintained at a high temperature to flow properly.