Several types of junction boxes

Junction boxes are enclosures that allow access to electrical wiring for connection, distribution, and protection. Several types are used in residential, commercial, and industrial applications:

- Standard – These basic metal or plastic boxes mount to studs or joists and come in round or rectangular shapes. They are available in a range of sizes and depths.

- Weatherproof – Weatherproof boxes feature gaskets and durable covers that keep moisture and dirt out from wet locations like outdoors or bathrooms.

- Fire-rated – Fire-rated junction boxes maintain complete electrical integrity and containment during a fire for a specified duration. They are required in firewalls.

- HVAC – Heating and air conditioning junction boxes are designed for the connection of HVAC equipment like furnaces, air handlers, and ductwork.

- Hazardous – Explosion-proof and intrinsically safe boxes prevent combustion of flammable gases and dusts in hazardous industrial settings.

- Underground – Underground boxes provide access to buried wiring and feature waterproof designs tested to ANSI specifications.

- Utility – These large, outdoor boxes mount on poles or exterior walls to connect utility service wires to the main electrical panel.

Choosing the right type of junction box is important for safety and code compliance. Licensed electricians determine the suitable model based on the application and environment.