A junction box is an electrical enclosure that houses one or more wiring connections. The box protects the connections, which usually contain vulnerable points such as wire splices, from environmental conditions and accidental contact.
Can you splice wire in attic? Open wiring splices in your attic are dangerous. As per the national electrical codes, these splices should be placed inside a covered electrical junction box made of plastic or metal. Wires should be placed inside a covered junction box because if the connecting wires become overloaded or loose, they can get heated and cause sparks.
electrical junction box
Additionally all junction boxes in attic should be under a face plate. Concealing a junction box entirely within the wall is prohibited. However, hidden junction boxes may still be encountered, posing a challenge when attempting to locate them.
Types Of Junction Box
Types Of Junction Box
The National Electrical Manufacturers Association (NEMA) categorizes junction boxes based on their usage. An outdoor junction box have NEMA 3R or 4 labels, while indoor ones are labeled NEMA 1.
How To Install A Junction Box?
When installing junction boxes, avoid placing a metallic box in a nonmetallic raceway (enclosed tube for wire protection) unless you ground the box with a wire.
One-Gang Plastic Nail Box
Commonly used for nonmetallic-sheathed cable with a thick plastic coating.
Guards against damage and accommodates outlets and switches.
Two-gang Plastic Face Nail Box (for outlets and switches)
Ideal for tight spaces with limited nailing room.
Shallow depth provides more room for hammering in nails.
Metal Pancake Box (for lighting fixtures)
Approximately 3 to 5 inches in diameter.
Mounts flush with finished drywall onto the framing surface.
Four-square Metal Box (for receptacles and switches)
Uses raised rings for single, double, triple, and quadruple gangs.
Suitable for surface-mounting with electrical metallic tubing (EMT) or flex conduit.
Can use metal-clad cable, but wrapped in aluminum or steel sheathing for wire protection and minimizing electromagnetic field (EMF) exposure.