I am trying to attach an electrical box to the brick wall behind it because there is no stud nearby. I have tried using the blue masonry screws but they either don't go into the hole I drilled because it the hole is too narrow or else the hole is too wide and the screws are gripping nothing at all. You can pull the box out of the wall by poking it with your pinky finger. The screws say they are 3/16" so first I tried a 1/8" drill bit, too small, next I tried a 5/32" drill bit and it was too big. I attempted using those masonry nails, first the spiral nails and then the kind that comes in a kind of metal sheath, but it's impossible to hammer them into the wall when there's an electrical box in the way of your hammer.

So what are you supposed to use? And are you supposed to be attaching the screw or nail, whichever is recommended, into the mortar or the brick? If you go into the mortar aren't you going to speed up its disintegration and create problems in the future? It tends to crumble when you drill into it, from what I've seen. But what do I know.

 

When I have to mount a box to a brick wall. I have used all kinds. There are some that are drive rivets. They come in a few different sizes. I used the 5/32. With a hole drilled 5/32, they slip in the hole,and you drive the pin down into it, and it flares out the bottom. I use those if I don't plane on removing the box any time soon.

I have used wire. Yes wire, but before anyone say anything. It does work better than some of the more expensive anchors.
I drill a 5/16 hole. Then place a piece of #12 stranded wire all the way to the bottom of the hole. Do not strip the wire. Cut it off flush with the surface. Then use a screw the same size as the wire core. It will not come out.



Travis

 

I don't know if the drive rivets will work because I don't know how I'll drive them in, working around the confined space of the box.
But the stranded wire, unstripped? That sounds like it might work. I'll try it tomorrow and let you know what happens.

 

Got some slightly thicker screws and screwed them in at angles instead of straight. That seems to work.

 

The blue screws you refer to are Tapcons(or similar). They require a drill bit that you have to buy. I tried using standard bits but the had the same problem as you. Buy a bit and they work properly. The problem is that you need a bit for every size. They can't be removed and re-inserted. It is a one time thing.