Ok, here's the problem. I have a coat rack that was installed poorly by the previous owner, who firstly installed it upside down and then secondly didn't use any drywall mounts. It came right out of the wall. I purchased some toggle bolts and some dry wall anchors only to discover what I believe is concrete behind the drywall (the back side of the wall is the elevator shaft).
Given that I cannot damage the concrete (it belongs to the condo's common property), and all of the drywall hangers I've seen are either too long or rely on the backside of the drywall being open, is there any way to mount the coat rack safely?
Any attachment should probably be able to take at least 50 lbs of weight, given I live in Canada and it will be holding up to five winter coats, mitts, hats, scarfs and it has a shelf above it where I occassionally put books and the like. Also the coat rack only has two holes for screws.
Best Answer
To be sure of a sound attachment, you need to attach into the concrete. Anything else will almost surely fail. Plaster does not have the structural strength except where you can spread the load over a large area from behind the plaster, and even then it is iffy.
As suggested by others, to attach to the concrete, you can use tapcons, concrete expansion bolts, or expansion anchors that you put screws into. Any of these will make very small holes in the concrete and not compromise its strength. These holes could easily be filled when you leave.
SUPPLEMENT BASED ON COMMENTS: You need to know what you are drilling into if you go that route.
A very different approach would be to create what is basically a free standing rack and then fixing it lightly to the wall.
The existing rack could be screwed or bolted to the top of the face of 2 upright hardwood boards, maybe 1x3s, as tall as you need the rack to be. The bottom of those uprights would be attached to a foot extending out from the wall about 12 to 15 inches. A brace would be attached on a 45 degree angle from the far end of the foot to a spot on the upright about 12 inches up.
The braced feet will counteract the downward pull of the coats. You could even attach a flat board to the tops of the feet to make a shelf for shoes, etc.
This whole unit could then be screwed into the wall through the uprights into plastic anchors in the drywall. This is just meant to keep it from shifting, not supporting the weight of the coats.