Lighting upgrade step-by-step

[Uranium235]

Now that I've been a member here for a whole 3 days, I shall begin asking questions in earnest!

One of my upcoming projects is a lighting upgrade. 3-car garage, with a single incandescent bulb per bay. I plan to remove those incandescents and install 2 4 foot T-8 fixtures instead. I am thinking the new fixtures will be attached to the ceiling perpendicular to the garage doors; that way I can put one of them directly over the hole left by the old light. I have access to the attic above the garage, where I can only assume there's a box over each incandescent light. The plan is to tap into that box and run wires to 2 fixtures from each of the 3 light boxes. What's the easiest how-to? And do I need to add 3 boxes, one above each T-8 fixture that isn't going below an existing box?

I do have a little basic homeowner type wiring experience, installing ceiling fans, replacing switches and outlets, adding outlets, etc. But never added additional lighting where there was none.

Matt

 

[DC73]

Yes, you'll need to add ceiling junction boxes for each light fixture. Since you have attic access, it'll be pretty easy to run power to the new boxes from the existing boxes.

DC

 

[Uranium235]

That's what I expected. So is a ceiling junction box different than a wall box? Should I use a new work box and go in from the bottom or old work and go in from above?
And is a ceiling junction box for lighting going to be different than a ceiling box for an outlet? Clearly I need to go to Lowe's and do some looking around tonight.

 

[HotRod68Camaro]

I just did this in my 3 car. I used old work boxes. They slide in from the bottom and tabs get screwed tight to the drywall. Ceiling boxes will be different for lighting and switching/outlet. I didn't attach the light to them so i could choose either. I went with the circular boxes as they allowed me more room for wiring.

 

[DC73]

So is a ceiling junction box different than a wall box?

Yes. Get a round plastic ceiling junction "old work" box. Easy to install from down below. Just trace around it on the drywall, cut the hole, insert and tighten the screws which will swing the ears that holds the box to the drywall into place.

You could also install a "new work" box but you'll need to either cut the hole near a joist so you can attach it or you'll need to install some blocking between the joists if you don't have a joist in the right place.

The box you choose may not handle the weight of the fixtures you want to install so make sure you have a way to securely mount the fixtures. An old work box is only supported by the drywall itself unless you install some blocking above it to carry extra weight.

A ceiling fan rated box can carry much more weight than a standard box but you'll need to attach it to a joist or to blocking between joists.

Since you're installing 4' T8 fixtures, you might be able to attach the fixtures directly to joists. If so, you won't need to worry about the weight carrying capacity of the box you choose.

DC