Around 1300 hrs today, Engine 3-12 responded to Eastgate Plaza for smoke from a building. Engine 3 was out the door right after dispatch. As engine 3 approached the scene, a heavy black column was seen from the building. Contractors were in the process of demo work when a pile of roofing materials caught fire and extended to the roof. Engine 3 arrived first on scene and stretched two lines to the building. Truck 30 arrived next and was supplied by E3-12. Crews remained on scene for over two hours operating.