When to Use a Metal Electrical Box?

A metal electrical box is an enclosure housing electrical connections. Junction boxes protect the electrical connections from the weather, as well as prevent people from accidental electric shocks.

You should use a metal electrical box if:

1. You're using metal-sheathed BX cable. Metal-sheathed cable is designed to be used with a metal junction box to ground the wires.

2. It's extremely important the electrical box is securely attached to a stud. The rigid and warp-resistant nature of metal electrical boxes means they're compatible with the heavy-duty screws you'll need for an extra-secure stud attachment.

3. Your project is in an exposed interior space. Some interior locations, such as unfinished basements, will have non-recessed electrical boxes directly attached to a surface (usually a masonry wall). Since these applications leave wires more exposed, you should use a metal junction box to protect them from damage.

4. You need a more durable type of electrical box. Some plastic electrical enclosures can be damaged if they're placed under pressure. Metal electrical enclosures are generally more resilient.

These aren't the only circumstances in which you should choose a metal junction box, but they're some of the most important. If you've decided a metal junction box is a right call, see our guide to metal electronics enclosure options for some great choices.