Our master bedroom has a walk in closet with one of the ugly industrial looking tube style flourescent light fixtures. I bought a much nice looking flush mount LED fixture but I'll have to cut a hole in the ceiling and install a junction box to install it. Right above this ceiling is the unfinished attic and the junction box will be in a joist bay with fiberglass batts in it. What is the proper and safe way to ensure that the fiberglass insulation is protected from the wiring in the junction box? i don't want to create a fire hazard.
Use conduit and make sure you seal up the junction box and those bad wires won't be able to get to the insulation. If you can, though, move the bats and mount the box above them on a rafter support or something. Then put your insulation back in place.
conduit is not necessary but the junction box should be mounted as griz said above on a rafter/joist. Junction boxes can not be buried, must be visible.
Check your local code. In my area any wiring that passes into one floor from another requires conduit and to have the hole sealed around it with a fire-proof substance.
The wires coming from the fixture are onyl about 6 inches so how would I be able to install the junction box above the insulation?
You don't mount above insulation, you mount it under...just have to move insulation to do the install, then put it back. Basically you will just figure out where you want it, find a structure to mount it (or screw a block in between the joist to mount the box) drill through the plaster/drywall to locate, mark the hole, cut it out, mount the box, install the wire into the box using a box connector (assuming romex wire) then seal around the box so to not make an air leak into the attic space, install light. If your wire is too short then you can splice it, but the splice must be put in a junction box, and someplace where it will be permanently accessible incase someone needs to get to it in the future.
I had planned on just cutting a hole in the ceiling and sticking a round metal junction box in it and then running the romex into that and connecting the light fixture to the romex inside of that. I was goign to make sure there was no insulation on top of it or within 3" on any side. The only thing I hadn't figured out was how to secure the junction box.
If the fixture is right near the joist, you can just screw the new junction box into the joist. If it is not right next to a joist, you can use a ceiling fan hanger, which spans from one joist to the other. Another option would be a plastic round ceiling box with the three "wings" on them that will open up as you tighten the screws.
Good point on the firestop, no conduit needed here, As said might want to check locally. If you are just mounting a ceiling box for a fixture, no need to worry about insulation contact. Every house in america has ceiling boxes with insulation on them. If you add a junction box for a wire splice it must remain accessible. Sounds like you are adding the box to mount the fixture , not extend the wire.
Yes basically there is a hole drilled in the ceiling now with a piece of Romex in it that goes into the existing tube style flourescent fixture.. I bought a flush mount LEd fixture that cannot use the existing hole because it is not centered in the closet. So I'll have to drill a new hole and install the junction box in that. Just connecting the existing Romex to the new LED fixture but want to make sure I do it properly so it does not create a safety hazard in any way.
There is no hazard with insulation touching the junction box, wire, or anything else associated with this project. I think you may have read warnings about insulation contact on can lights which some can lights prohibit, the cheap ones. Good can lights are IC rated for Insulation Contact. A normal junction box has no such prohibitions. If you have access from above then this is easy. Pull back the insulation, locate the desired position of the new ceiling box from below, push a nail through the sheetrock and then go back into the attic and make sure that there is room above for the box, then use a ceiling box support system (fan box or the weaker version for lights) and mount the box to the framing so that it is located where you want it. Run the wire. Replace the insulation by trimming it for a tight fit. Put up your new fixture. I do not like old work boxes that mount to just the sheetrock especially in this application where the weight of a future fixture may pull it down! Your new LED fixture isn't a can light is it? I worry about your words "flush mount" but I also know that many of the new LED fixtures are pancake thin.
Those are called old work boxes if you go that route. Knowing the name will help you locate what you need.
I was at Lowe's the other day and they now make old work ceiling boxes that have a plastic hole saw mounted to the box. I wish they had these when I was in the buisness
