Are junction boxes required for flourescent fixtures?

[mnster]

I've been looking at lights recently for the garage. The wraparound lights I was looking at require junction boxes for mounting. However, the basic 8ft T8 strip lights are on sale this week at Menards. In mounting it says you punch a hole in the back for the wires to run thru. Obviously, this would greatly simplify wiring the fixtures for me on my finished drywall ceiling vs. Installing junction boxes in the ceiling. Can I drill a hole in the drywall poke the wires thru to the light fixture or is a junction box still required?

Tried to search but it seems everywhere I could look was either retrofits of existing fixtures or unfinished ceilings. So I wasn't able to get a straight answer.

 

[offroadsteve]

If the instructions say to just punch a hole in the back of the enclosure, then the wire chase in the fixture acts as the junction box. You do need to install a grommet in the hole to protect the wire, but no box is required.

Edit: what I meant by grommet was "clamp", either metallic or non-metallic. I was thinking those non-metallic clamps are kind of like grommets. Sorry for the terminology confusion.

 

[eljefino]

+1 on the grommet, I use these things on romex:

 

[pattenp]

If the fixture has a 1/2" knockout I believe you need to use either a metal or plastic NM clamp, not just a grommet.

 

[Charles (in GA)]

Like the metal one used above, or a plastic one like one of these.

Charles

 

[NUTTSGT]

I used a Romex (NM) clamp when I hung my strip lights. I just drilled a hole in the ceiling larger enough to accommodate the clamp.

Now that I say that, I know I did have a 1/2" spacer between the fixture and ceiling.

 

[BFBOB]

Romex clamp, but put the clamp on the inside of the fixture. Then if you need to rewire, you can get it out without removing the fixture.

 

[NUTTSGT]

Romex clamp, but put the clamp on the inside of the fixture. Then if you need to rewire, you can get it out without removing the fixture.

Now that sounds familiar to what I did, maybe the spacers were to clear the conduit nut.


lol, maybe I need go out and check to see how I did mine tomorrow ?

 

[laser3kw]

Hello Rockford...........

 

[mrjaw14]

No you do not need a seperate box. The fixture is the box as long as a suitable knockout and cable supporting conenctor is used, meaning no grommets, yes to proper clamping style connector that will hold the cable in place where it cannot be tugged out or pushed in once tight as others have mentioned. Just run the romex or conduit to the fixture. You will need to follow standard cable support rules, such as first staple or hanger within 8" I think it is and then 4 1/2' there after.

 

[JoeFin]

I've been looking at lights recently for the garage. The wraparound lights I was looking at require junction boxes for mounting.

Tried to search but it seems everywhere I could look was either retrofits of existing fixtures or unfinished ceilings. So I wasn't able to get a straight answer.

Only when you are breaking a "Fire Wall" aka: "5/8 *** Fire Rock"

 

[shamrock12]

Junction box is not required in just about any fluorescent fixtures unless you have multiple cables coming in. Use cable clamps that is appropriate for the type of cable you are using (romex, metal clad, etc). They should be installed on the OUTSIDE of fixture, not inside. This means the locknut should be installed on the inside. This way the exposed wires will be on the "smooth" side of the clamp. Plus, it will be much easier to replace the fixture in the future.

 

[mnster]

Junction box is not required in just about any fluorescent fixtures unless you have multiple cables coming in.

So with 16 fixtures I'm imagining the only way to run them is with junction boxes as a wire entering and a wire leaving the fixture isn't allowed? Wires would have to be wire nutted in a junction box and a single cable run to each fixture?

 

[rockwithjason]

that is not necessarily true. you can get away with an in cable and an out cable but if you have 3 or 4 cables in a fixture you need to rethink your routing.

 

[shamrock12]

Jason is right, it's fine to have a couple cables going through the fixtures. You actually could double stack two flat romexs (two current carrying conductors in each cable) through a single clamp.

It might not apply to you but they also make a clamp for securing two metal-clad cables together so only one clamp is used instead of two.

 

[roc_on_the_rocks]

So just to confirm... to add LED light fixtures to the finished drywall ceiling in my attached garage, I can just drill holes (1/2in ?) in the drywall (to pass the Romex cable through), no need of adding individual junction boxes for each fixture?

In case it matters, there's loose fiberglass insulation above the drywall ceiling.

Thanks guys!

 

[MattT]

Only when you are breaking a "Fire Wall" aka: "5/8 *** Fire Rock"

Is that just for walls or does it also apply to ceilings? The OP just mentioned the garage is attached so the ceiling may be fire rated.

 

[roc_on_the_rocks]

So just to confirm... to add LED light fixtures to the finished drywall ceiling in my attached garage, I can just drill holes (1/2in ?) in the drywall (to pass the Romex cable through), no need of adding individual junction boxes for each fixture?

In case it matters, there's loose fiberglass insulation above the drywall ceiling.

Thanks guys!

Is that just for walls or does it also apply to ceilings? The OP just mentioned the garage is attached so the ceiling may be fire rated.

I think Matt's right.


Anyone wanna chime in?

 

[Zeke]

Limited penetrations are allowed in a FR wall. No less than 24" from each other and no 2 in the same joist bay. This references boxes, plastic and steel ans should apply to any electrical penetration. Running the cable through the ceiling and securing it with a cable camp as it enters the box is required as stated above. In addition, I believe that the cable hole must be closed up by mudding or using fire rated caulk before raising the fixture to cover the entry.

So, if the fixtures are wired parallel with several on the same circuit, it would seem you must bring the 2 cables through the ceiling together and enter the fixture stacked in a single clamp connector. The typical connector will take 2 cables easily.

If I were inspecting this installation I would be concerned with the lock ring and threads on the top side of the fixture when the fixture is tightened up to the ceiling. Obviously, all of this applies to surface mounted fixtures and they must fit to the ceiling in a way that no 'romex' is exposed outside of the metal fixture housing. So, I would make room in the penetration by making a large enough hole, and a short recess, for the threaded side of the fixture to sit in and then fire caulk it that way.

Pull the fixture up and secure with the clamp loose so that the wire doesn't fold and then tighten the screws after the fixture is mounted. I mean, what more can you do?

Note added as an edit: For those that want to get particular, if a box is used, it must be 16 sq in or less and no more than 100 sq in of penetration permitted in any 100 sq feet. I think you're safe with only the cables coming through.