Floating shelves are a simple but practical addition to any wall. They are more versatile than traditional bookshelves and can easily hold display items as well as practical ones. However, over time a floating shelf may begin to sag. There are numerous causes for a sagging shelf, and fortunately, all of them are easy fixes. Adding support to a sagging shelf can prevent it from falling, breaking or being permanently damaged.
Take everything off the floating shelf to examine the shelf more closely.
Look at the brackets underneath the shelf first; brackets that have been spaced too close to the edges of a shelf can cause it to sag.
Move the brackets 1 to 2 inches in from the edge of the shelf. Remove them from the wall with a screwdriver and replace the screws in the brackets' new position.
Add a third bracket to the centre of the shelf to hold up the sagging middle. Attach the shelf with screws. Make sure it is even with the other brackets.
Replace items on the sagging shelf; put the heaviest items at the ends of the shelf and lighter items in the middle.
Before you add support to a sagging shelf, check to make sure it has not cracked or split; if it has, the shelf needs to be replaced, not supported.