The answer depends in part on whether it's real portland stucco, or a veneer like Dryvit or eefis.

 

Not really sure what it is. Appearance wise it's not ultra rock-hard, I think it's a thick coating over sheathing/moisture barrier, and about 20 years old.

 

Sure would be nice to know how thick it is until you get to the sheathing. Short answer is, I use a grit hole saw most of the time to get the stucco out of the way, and screw a (generally an octagon) box to the sheathing. If I was doing that work, I'd try to see how thick of a wall fininish material I'm dealing with, then formulate a plan from that.

 

If it's 20 years old it's probably conventional stucco(portland cement), even if it is synthetic the brown coat(base layer) is portland cement.

But in all honesty you don't need a box seeing as the fixture is a junction box in itself.
When stubbing out your romex I like to beat a hole with a screw driver into the stucco just around the circumference of the hole you need to drill through the sheathing. You can use a hole saw if you like but the conventional stucco is usually thick and the synthetic is harder on tools.

 

But in all honesty you don't need a box seeing as the fixture is a junction box in itself..

I'm gonna have to ask you for a code citation on that one, brother.

 

What do you mean by "panic box"?

 

An old work box.

 

No need to panic! I always carry some (both regular and ceiling fan) on the truck.:thumbup:

 

Thanks for all the replies. About that box requirement.......Ok so if the back is open you need one, if the back is closed and has a KO you don't need one.
How about if you have a bathroom light bar, closed back with a little (aprox 3/8"). smooth hole??
(The hole doesn't appear to be a KO that you can fasten a romex connector to.) Pretty common

 

Most decrotive(spelling) light's that are majority in the front of the building do not need a j-box If,If,the point of exiting is directly behind where the light is going to be mounted

Now that been said, Most flood light need a weather proof J-box

 

Now I'm confused--any code reference on this.

 

I could never find the grit hole saw bit in 3.5 inch, so I trace a round 3.5 inch cut inbox on the wall and drill lots of 3/16 th holes with my cordless hammerdrill and then finish it off with my hammer and cold chisel. Ive done a ton of these in socal, mostly adding coach lights onto garages!

 

Coach lights are a future project for me in a number of locations. The house is concrete block, got the hole, got the box, got the wire. What's the best way to fasten the box to the block? Diamond saw the hole and TapCon from the sides?

 

Installing a flush box in concrete block for old work is always a problem. I cut the hole by whatever means and install the box either by grouting it in with mortar or fixing it in place with one of those 2 part epoxy caulking kits. Doing it yourself isn't so bad, but paying an electrician to do it gets a little pricey. It takes two trips. One to cut the hole and fix the box in place, then another to return once the mortar or epoxy is set up to hang the light. I personally don't think you'll have much success Tapconning through the sides of the box into the inch or so thickness of the face of the block. There are no trick old work boxes on the market yet made especially to install flush in concrete block. American ingenuity is still required. :notworthy

 

md, epoxy was my first thought, so was code. I have some that will sustain 480*. NEC doesn't seem to address aero-space tech. TapCons do have the ability to 'blowout' to either side of the block.

 

Since you're interested in the code, it's pretty basic when it comes to mounting boxes in existing finish material:

314.23 Supports
Enclosures within the scope of this article shall be supported in accordance with one or more of the provisions in 314.23(A) through (H).​

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(C) Mounting in Finished Surfaces. An enclosure mounted in a finished surface shall be rigidly secured thereto by clamps, anchors, or fittings identified for the application.
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(G) Enclosures in Concrete or Masonry. An enclosure supported by embedment shall be identified as suitably protected from corrosion and securely embedded in concrete or masonry.

​

It is important to note that epoxy and similar compounds is a chemical anchor.​

 

Sparky, my house was built for the contractors daughter, the block is barely structural. I find more pours than I care to.

 

Then I'd say blow out a big hole(not too big the light won't cover it).......float the box to the fixture, assuming it's large and has seperate mounting holes to the building. If it doesn't then perhaps through bolt it..... or modify a regular box with things(bolts, nuts, washers) thru the back and use morter like MD mentioned.