Builders FirstSource - Salem MA Yard - 33 Mason St [Material Handler / Freight Handler] As a Load Builder at Builders FirstSource, you'll: Perform loading and unloading materials onto or from pallets, trucks or customer vehicles and install strapping; Drive various lifting devices to move products, equipment of materials around the warehouse, shop or yard; Perform load-building, determining the appropriate weight, composition, and placement of load...Hiring Immediately >>