Mistake: No electrical box | Never connect wires outside of electrical boxes. Junction boxes (or a J box) protect the connections from accidental damage and contain sparks and heat from a loose connection or short circuit.
When would you use a junction box?
Youll need a junction box if you cant make the connections inside an existing electrical box. You should install the box with the opening facing out from the wall so all the wires inside are accessible. Like any electrical box, it should be installed so that the edge of the opening is flush with the wall.
Are junction boxes acceptable?
A junction box is perfectly okay if you can see it or easily access it. The problem is junction boxes used in inaccessible places, like under floorboards, where they will be hidden. So if you are planning on using them in a loft thats not a problem.
Romex wire and plastic junction boxes are frequently used together, but metal enclosures may be acceptable as well (depending on the project). If youre using metal-sheathed wire, you may be able to use plastic enclosures, but youll always need to take the appropriate steps to ground the wire first.
Can I use an outlet box as a junction box?
During remodeling projects, you may need to convert an existing plug-in outlet into a junction box, perhaps if youre going to build cabinets or closets in the area. You must keep the junction box cover accessible, but its dangerous to simply leave an outlet in a place difficult to reach.
Can a junction box be hidden in a ceiling?
Electrical wires run behind the walls and through the ceiling of your home, meeting at junction boxes. It is a safety hazard to completely bury a junction box in a wall.
Can a junction box be inside a wall?
Junction boxes must be installed where they are always accessible; never install a junction box in a concealed wall or ceiling space where the box cannot be accessed in the future. Junction boxes also must be covered with solid covers with no holes.
Is it OK to splice electrical wire?
Fortunately, no. Savvy electricians can splice wires together, safely adding the length they need to reach their destination.
How many circuits can you put in a junction box?
There are no limits on the number of junction boxes (without devices) in any particular circuit. Each piece of utilization equipment reduces the maximum allowable load by it nameplate rating, 180va for each receptacle, and each light fixture at its maximum labeled lamp wattage.