Mount outdoor outlet to stucco wall

The instructions tell you to mount the box using the tabs in that plastic bag. You might be able to punch out those holes with a drift punch but I would drill them.

There are only 2 tabs in the plastic bag. If I am mounting the box vertically, do i install the tabs diagonally, that is, one at the top left and the other at the bottom right of the box? Would it be strong enough to hold the box securely on the wall?

I drill them and use screws through he back

Two diagonally should do the trick. You could also put a big dab of construction adhesive on the back side to stick it to the wall to back up the screws/tabs, I would think. Going to be hard to get off in the future....

Two screws on a diagonal should work fine as long as they are long enough to find something to bite into behind the stucco.

I'm not sure why you need the tabs. I would drill holes in the back of the box and run my screws through them. Use washers if you want a little more support around the heads.

Construction adhesive might help, but it's only going to be as strong as the stucco's adhesion to the wall since that's what you'll be gluing it to.

No matter using tabs or drill through the back, I am thinking of using plastic anchors in the stucco. Would that work? The cement stucco is about 1/2" thick, and the plywood behind it is another 1/2" thick...

Thanks

Why not just use screws that are long enough to grab the plywood?

I've never dealt with "cement stucco" so I don't know how well a plastic anchor would work in it.

I'd be concerned that the use of the receptacle would loosen the anchors fairly quickly.

Is the interior of the space accessible? *Bolting* it through the plywood would be about as secure as you're going to get.

Of course, mounting it where you could screw into a stud or rim joist would work pretty darn good also.

I wouldst use #10 x 1.25" SS sheet metal screws That gets into the plywood. The stucco might just pop off if that is all you are holding onto.

Or just use wall anchors (plastic plugs) in the stucco.

On 4/13/2010 1:16 PM Robert Neville spake thus:

Nah.

As others have pointed out, that's a weak way to attach anything to stucco. After all, it's at best about 1/2" thick. Just use screws long enough to bite into the wall sheathing (plywood or 3/4" boards).

Use two toggle bolts. Drill 1/8" holes in the back of the box and larger holes into stucco and through the plywood. Mount the box and tighten it up. Finish with a bead of caulk around the box to keep critters and water out.

My pool timer and landscape lighting transformer are mounted with "plastic anchors" in the stucco.

That may be fine for "fixed objects" but I don't think I'd trust (per the OP) an "outdoor outlet box" mounted with plastic anchors in stucco.

I have lot's of different cords that I plug into outdoor receptacles and some of them take quite a lot of force to engage/disengage. By "a lot" I mean more than I would want to subject plastic anchors in 1/2" stucco to.

Agreed, hence my suggestion to use toggle bolts on the box, if he has ply behind the stucco.

Also, I would avoid plastic anchors for the outlet box.

Unfortunately that only works if there is OSB or plywood as sheathing. In a non-stress location, it could likely be fiberboard behind the stucco that won't hold a screw.

Toggle bolts thru the stucco and plywood should hold up fairly well if the outlet users are not gorillas.

The OP has already stated:

"The cement stucco is about 1/2" thick, and the plywood behind it is another 1/2" thick... "

If we can't trust the OP, who can we trust? ;-)

On 4/13/2010 8:20 PM Robert Neville spake thus:

Fiberboard as wall sheathing? Really? Sounds kinda flimsy.

Never seen it but I'll take your word for it if you say so.

I would attach that box using molly bolts, sealing them individually prior to tightening them...

How are you planning on getting the power feed to this outlet box are you going to use a conduit stub through the wall or find moisture rated romex cable and a rain tight connector to fit in the space at the back of the box...

Simpler to use a conduit stub and run the wires that way...

Good advice on sealing the box to the wall with caulking, but you really do want to fill any holes you make around the power feed and the fasteners before you put the box in final position, as the caulk can fail and little bugs can climb up from underneath and enter through any little holes you leave behind the box...

If you are worried about "more support" for that box, you could purchase more of the tabs and screws at an electric supply house and use all four mounting points, but that seems like overkill... Are you planning to stand on this box after it is mounted on the wall or something ?

~~ Evan