An encapsulated bulkhead for use as a void filler to secure and protect cargo loads during transportation, such as in rail cars or trucks, is described. The encapsulated bulkhead includes a bulkhead member and an encapsulation or coating. In one embodiment, the bulkhead member includes two planar parallel deck sheets, a planar peripheral side member, and a honeycomb cell core, which may be made of corrugated paper or other paper. In another embodiment, the bulkhead member is a uniform expanded polystyrene foam. The coating is a water-resistant material which may be an elastomer, such as a polyurea, polyurethane, or polyurethane/polyurea hybrid. A method for encapsulating a bulkhead member is also provided. The method includes the steps of providing a bulkhead member, spraying the bulkhead member with the components of an elastomer to coat or encapsulate the bulkhead, and allowing the components to cure for a period of time sufficient to form the water-resistant elastomer.