Joist hangers are the best option when hanging a shelf or heavy picture on your wall. Especially in areas where a wall stud is not available, a joist hanger will give the shelf, rack or picture additional support. Joist hangers, sometimes called mollies, expand once they are in the wall so that the hanging has up to three supporting areas.

On the Other: Joist Hangers May Be Too Large

Unless the rack or shelf you're hanging is incredibly heavy, you don't need a joist hanger. A pair of heavy-duty screws works in most cases, especially if you use a stud beam for support. Screws make smaller holes in drywall than joist hangers, and so the cleanup is lessened as well. Screws hold tight over time as long as the load is not too heavy.

Bottom Line

If hanging a heavy shelf, or if the shelf will be used to hold large, heavy objects, such as a stack of books, heavy-duty screws will work. If the load requirements are large, however, a joist hanger is the best option because joists offer additional support. When using joists, the holes are less likely to sag or get larger over time, which can cause the shelf or rack to lean or even fall.

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Handyman USA: Shelving Q's and A's