An expandable rack including a plurality of vertical frame members and a plurality of adjustable shelves is disclosed. Each adjustable shelf is at least partially supported by at least some of the vertical frame members. Each adjustable shelf comprises a first portion and a second portion. The first portion includes a lateral beam and at least one first arm extending perpendicularly from the lateral beam. The first arm includes a polygonal cross-section. The second portion includes a lateral beam and at least one second arm extending perpendicularly therefrom. The second arm includes a polygonal cross-section. The first arm is dimensioned to fit within the second arm in a telescoping relationship.