How do you reinforce bookcase shelves that are sagging under heavy loads?

Sagging shelves in a commercial bookcase indicate overloading beyond the rated capacity or shelves that are too long (unsupported span too wide). Solutions: (1) add a center support rail to the shelf if the unit allows it; (2) add a center support leg underneath sagging shelves; (3) redistribute the load to more shelves; (4) replace with thicker shelves if the unit supports different shelf thicknesses; (5) replace the bookcase with a heavier-duty metal unit rated for higher loads. Prevention is better than fixing — never exceed the rated load per shelf. FindOfficeFurniture.com can recommend heavy-duty shelving options — call 888-719-4960.