How To Install A Junction Box In The Ceiling (3 Easy Steps)

Before you decide to install a junction box or do the wiring by yourself you need enough experience for safety. Because electric jobs can be extremely dangerous and life-threatening. How To Install A Junction Box In The Ceiling is pretty straightforward and anyone can do it at home. 

To install a junction box cut a circular hole in the drywall ceiling. The junction box can be hung with a metal bar or screwed down with the joists or even a flush mount with a drywall plate. So use any one type to install the box in place. Run through the wiring into the holes on the box and tighten all the screws to fix it in place. Then you can finish the rest of the installation. 

So the steps are easy and anyone can follow but you never know what problems you might face during the process. Be prepared and read the whole thing to learn more about it in detail. 

How To Install A Junction Box In The Ceiling

If you want to install a junction box in the ceiling it can be done in many ways but here we have discussed the easiest one so anyone can do that on their own. 

Step 1

Before starting any electrical work, first, make sure the power is off at the breaker. If upgrading to an existing fan or light fixture, unfasten the canopy or black plate to disconnect the mounting and wiring connections to remove the old fixture. 

Note: If you find the old box is mounting directly to the joist, then choose one of the other electrical box options designed for the bottom or side of the joist mounting. Unfasten and remove the box to expose the hangar or the splitter bar. For wide spans with a flimsy hanger bar, you can try pushing the bar up until the two channels separate apart. You can also try cutting the bar for an easier approach. 

How To Install A Junction Box In The Ceiling

Step 2

To mount the fixture properly, you can also cut a hole in the ceiling for a proper electrical ceiling box. Use a stud finder to figure out the box placement. To cut a hole in the ceiling using a battery-powered Dremel fitted with the Dremel cutting kit. Take the drywall circle out and put the new junction box in place. 

Step 3

There’s a little flap on the bottom that you have to push and it makes a hole for wires to come through and drill all the screws in place so it remains in place. There will be a mounting place that helps your light or fan to be mounted on the ceiling box. Now you can place the lighting system in place and you’re done. 

How To Install Ceiling Light Mounting Bracket 

Usually, the mounting plate bracket comes with two screws with a long flat plate that will go up against the junction box and will be fastened on with the screws. The threaded piece that hangs down is what the light fixture is going to fit onto and the nut at the bottom will hold that light fixture up. The whole process will start something like this: 

  • Screw one of the screws halfway as a guideline 
  • Then slip the mounting plate onto that screw 
  • Now install your second screw 
  • If you are using a drill, when installing these screws make sure you don’t go too fast that you strip out your box
  • Wiggle that around to make sure everything is secure

How To Install Ceiling Light Without Junction Box 

If you want to install a new ceiling light where you don’t have any previous setup for this job, you have to re-do the whole installation process. But you have to test the new location for an electric connection setup with an outlet tester, a voltage tester, and a multimeter to keep you safe. 

So what you have to do here is, leverage the wiring of the switch, require the outlets, and then use the switch with a new Romeo wire coming up to the ceiling to install that light and control the light. This process will work when you don’t have excess from the bottom. 

Step 1

Use a stud finder, a measuring tape, and a level to measure out the area where your new wiring is going to be placed. Use painter’s tape to do the mapping. This mapping will start from where the light is going to sit and towards the outlet. Make sure not to hit any floor joint while mapping. 

Step 2

You might need to cut some places on the drywall to fish down your wires through the floor joists and the switch box. Cut the drywall with a small hand saw so you can have control. Make a circular cut for the junction box setup as well. 

Step 3

Use a fishing tape to run your Rolex wire through the load-bearing wall and then come back through the cavity going down. This way you can tape on your 12/2 Romeo towards the end cavity. 

Step 4

Now you can install the junction box into the ceiling hole and connect the wiring to see if the connections are working. If the light is working perfectly now you can leverage the switch. 

Step 5

Once you pull all the excess switchable hots out, you can wire all that up and test out the circuit to make sure everything is working. Lastly, fix the drywall with a new piece. 

How To Install A Metal Junction Box In The Ceiling 

When you’re installing a metal junction box you have to use a metal brace to hold the weight of your fan or a light fixture you’re going to hang on it. 

  • Turn off the power supply at the breaker before starting any electrical work. If upgrading an existing fan or light fixture, unfasten the canopy or backplate to disconnect the mounting and wiring connections to remove the old fixture
  • If you find the old fixture is mounted directly to the joist then choose one of the other electrical box options designed for bottom or side joist mounting. Unfasten and remove the box to expose the hanger or splitter bar. Push the hanger bar upwards to remove it
  • Make sure the opening is four and eight inches and expand the opening size if necessary. For new installs, a four and a quarter inch saw works great to cut the drywall ceiling
  • With the brace expanded to the approximate joist’s width insert it into the opening orienting the feet to rest on top of the ceiling panel. Make sure the bar is centered in the opening and then rotate the bar 5 or 6 complete turns to embed the teeth into the joist
  • Next, mount the bracket into the brace and Center within the opening. Prepare the box by removing the appropriate knockout and attaching the ground screw 
  • Pass the cable through the knockout opening and slide the keyholes on the bottom of the box over the two hex heads. Slightly rotate the box counterclockwise to hold it in place and then fasten the other two hex screws 
  • Then finish tightening all four screws. Push the inside connectors up the cable until it snaps into the knockout hole. Now your fan or light is ready for installation 

How To Install Ceiling Electrical Box New Construction 

For this type of installation, the first thing that we need to know is what we are putting on the ceiling for a covering. Usually, you have to put ⅝ inch on the ceiling and ½ inch on the walls. There are different kinds of electrical boxes on the market. So you need to determine which one you would like to go on with. These boxes go flat against a joist where you want to mount your fixture. 

So first you have to pick a center for your box to install. Use a stud finder to get a central place for the fixture.  Now bring the box up to the center of the joist where you will screw all the nuts with the joist. Once the box is fixed in place you can bring all the wirings up and attach them to the fixture. 

How Do You Install An Electrical Box In An Existing Ceiling? 

To install an electric box for a fixture you can go with the kit that will be appropriate to hold the fixture’s weight. Now if there is an old box and hanging bar you need to take it out and adjust the opening so the new one fits perfectly. Now follow the rest of the procedure explained down below:

Step 1

Now adjust the new bar according to the side joist’s width and fix it in place with screws by twisting it. Now mount the bracket in the middle where the box will sit. 

Step 2

Next, on the back of your box, there are holes on the sides where the wiring will go but they will be temporarily closed with a loose cover. So you can push on those to open the hole. 

Step 3

Now run the wires through the holes and make sure the screw holes are in place. Tighten the screws with a drill or screwdriver and your new box will be where you can do the rest of the fixture installation. 

Install Ceiling Box With Hanger Bar

Before installing a ceiling box you need to make sure that you’re installing the correct one which can hold your fixture’s weight. You can attach the droop ceiling bar with screws or clip them on the studs. There will be a clip for the mounting brace that you need to attach in the middle of the bar.

Now take your box and knock out the hole covers. Run through the wires in the holes and screw them in place. Once the box is fixed you can proceed with the rest of the installation. 

Old Work Ceiling Box 

An old work ceiling box is used for remodeling purposes. The thing that’s special about this is it has wings that flip out. The way these boxes work is they hang on the drywall and not with the joists.

After you have it, if you cut a hole there’ll be a template to cut a hole into the drywall and this pushes through the drywall flushed all the way around. Then you’ll take a screwdriver to screw it in and as you turn it the wings will pop out and they end up gripping the drywall. Lastly, tighten the screws and do the wiring as usual. 


How Do You Wire A Ceiling Junction Box? 

To wire a ceiling box you have to cut a circle into the drywall ceiling, hang the box with a bar or flush-fit it onto the drywall or screw it with the joists, then run through the wirings through the holes of that box, and attach it with screws on the sides. Lastly, finish up with your fixture installation. 

Can You Put A Junction Box In The Ceiling?

Yes, you can. If there are existing wires then just place the box through the wires or you can cut a circle according to the box size to install it. 

Can I Install A Light Fixture Without A Junction Box?

To install any kind of fixtures like lights or fans or fire alarms it is always necessary to stay safe with those wires. So that’s why before installing a light fixture installing a junction box is always recommended. But you can install a light fixture without a junction box though. 

How Do You Install A Junction Box In An Existing Ceiling?

Cut a hole into the ceiling, hang or screw the box with the joists, insert the wires through the holes, and tighten the box with screws to fix it in place. 

Does A Junction Box Have To Be Attached To A Stud?

No, it is not always necessary. You can flush mount it or hang it with a hanging bar as well. 

How Do You Install A Junction Box Without A Stud?

You can easily flush mount your junction box with an old work ceiling box where there are wings on the sides that will rest on the drywall once you screw it down. 

How Do You Install A Junction Box On A Light Fixture?

To install a junction box for a light fixture, cut holes in the ceiling. Place a hanging bar with the studs and screw the clip to mount the brace in the middle. Then place the bracket on the hanging bar and attach the box with screws. Run through the wires in the holes and finish the rest of the light fixture installation. 

How Can I Extend My Electrical Wire Without A Junction Box?

According to the code, you can lock up a piece of Romex into the box which will give you better room to work with. To meet the code use non-metallic shearing from Romex extending at least a quarter of an inch through. Then you want to see from the end of the shearing to the end of your wire that is at least six inches with at least three inches extending past the box itself. 

Are Electrical Junction Boxes Legal?

Yes, they are. But you need to find the right kind of box to hold the weight of your fixtures and also install it according to the legal code. 

Are Junction Boxes Safe?

Yes, they are. They protect your loose wires from damaging and unexpected sparks which may cause short circuits. 

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Final Verdict 

No matter what kind of electrical work you are doing, you always need to have enough experience to solve the issue or it can result in dangerous situations. Especially when installing new fixtures and wirings be very cautious and if needed ask for professional help instead. 

I'm Jimmy, the creative mind behind Drawing from extensive expertise in home improvement, I founded this platform to help individuals transform their living spaces. My dedication lies in empowering homeowners with dependable advice, ensuring that every DIY project not only elevates your home but also enhances your lifestyle. Join me as we redefine homes, one project at a time.

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