Here's that shelf, since I can't put a link in my first post. And the WallClaws are at www.wallclaw.com.

Here is a link that might be useful: IKEA Varde

Which Varde product do you have? There are several wall-mounted shelf units and cabinets on that page.

In any case, very heavy shelf + vintage glassware = you MUST find studs to anchor to. If there are no studs, cut out a section of drywall and install some blocking to screw into. Don't take shortcuts here unless you're willing to see a whole shelving unit full of glassware hit the floor.

Sorry, I thought I copied the link to the specfic shelf.

So if the wall is about 5' wide, a single piece of blocking from stud to stud on either side should be okay? And I can just use 2x4 and nail them in at an angle, like toe-nailing?

I wonder if there is a way to modify the French cleat for this shelf. That way I wouldn't have to rip into drywall ...

Here is a link that might be useful: Varde wall shelf

I don't know what I was thinking. I know perfectly well that wall is exactly 30" long, nowhere near 5'.

First, I can't quite see how that shelf is designed, but the shelves don't look well supported on the back uprights to me. Not sure I would load those shelves heavily no matter how the unit was hung.

Second, how are you hunting for studs?

Finally, is this a place you rent or own? If you own, and there is no stud there, this might be a situation worth remedying properly rather than patchily (might serve you from both sides in the longer term), plus you might even be able to do something quite different there... for example, open wall and install studs and build a cavity-shelf between them.

KarinL

The shelves are actually really well-supported -- it's hard to describe but a long bolt goes through the back of each upright and about 6" into the shelf, where it screws into a sort of metal nut that gets slid up into the shelf from the bottom side.

I used a cheap stud finder and my guy and I both thought it must be broken because it kept giving us inconsistent readings. When I opened up the wall last night I found out why -- there's a conduit or pipe in there in one spot, and for some reason whoever built the wall offset the studs so they're in one place at the top of the wall, another place at the bottom of the wall and there's also a short horizontal stud (not where I need it, alas).

Tonight I'm going to add the blocking and close it back up. I'm still not clear on whether I should use nails or long wood screws, but in the absence of definite information I'll use screws to be on the safe side.

I've been wanting to repaint the kitchen so having to paint over the new drywall will be a good excuse to start that.

OK if you've actually been IN the wall I'm not going to argue with you :-)
To put a brace in I'd definitely use screws, possibly just because I hate whacking my house with a hammer, but there are other advantages. By the way you might like to take a picture of what's in the wall while it's open, with a ruler in the picture, to help assess where everything is for future reference.

As far as assessing the strength of your shelves, they may still have limitations, especially if they are built of softwood. The article below might be of interest.

Good luck!

KarinL

Here is a link that might be useful: Joint strength assessment

Interesting. Also reassuring, because the weakest joint in those tests failed at 135 lbs IIRC and there's no way I'm going to be loading anywhere near 135 lbs on each shelf. (They're pretty small shelves. A dozen mugs size maybe. I couldn't fit a stack of dinner plates on them if I wanted to.)

I put in the blocking, closed it up, and did the first coat of mud last night. This is my first time mudding, so we'll see how it turns out. The walls in this house are generally bumpy and full of poorly done patches/repairs under the paint anyway, so I have some leeway if the job turns out a little clumsy.

"...no way I'm going to be loading anywhere near 135 lbs on each shelf."

How you attach the case the the wall will determine the joint loading.

If the top of the case is used to hang it from the wall its joints bear ALL the weight of the entire unit plus items placed there.

If the sides are attached the weight is spread over multiple joints.

"If the top of the case is used to hang it from the wall its joints bear ALL the weight of the entire unit plus items placed there. "

I have a hard time visualizing how that could be true for this particular shelf -- have you looked at the pic? It's not a shelf with sides and a top like a cabinet or bookcase. The uprights are fastened to the wall, and each shelf depends on the uprights without being otherwise connected to the other shelves.

I'm not an engineer so I might be missing something here (and if I am, please explain it very specifically and in short words because I do want to know), but it seems to me like the uprights bear the weight of the entire set of shelves, and the only risk to an individual shelf really would be overloading it enough that its individual joint fails.

The uprights are fastened to the wall and each shelf depends on the uprights without being otherwise connected to the other shelves.

That's what Brick meant when he wrote "If the sides are attached the weight is spread over multiple joints."

The problem situation would've been if the shelf had been hung by one of the shelves instead of by the uprights. In that case, the weight of the whole unit would've been borne by the joints between the uprights and the shelf that was attached to the wall.

OK, that makes complete sense. I imagine if the whole thing were held up by one of the shelves, that shelf probably *would* just snap off. But as it is, the load should be fine.

You should have asked this question in Home Repair or Remodeling, but the correct way to attach a crossmember( I believe>to studs is by nailing. You could also use metal hangers in conjuction. Since you have used screws already, I think you would be OK. Next, you decide how high the bottom of your shelf will be and using a level make a horizontal line across your new drywall even with the bottom of the shelf. Next, decide how long a screw you will need to hang the shelf (thickness of the shelf plus the drywall plus depth into the crossmember you installed. Next, drill a 3/8" countersink hole on each side member, about 1/2" deep, in the shelf where you want to screw it to the crossmember you installed. Predrill the screw holes in the center of the countersink holes you just drilled (slightly less thick than the thickness of the screw) clear through the frame of the shelf. Now screw the screws in the shelf so about 1/8" protrudes. Line up the bottom of your shelf with the level line you marked on the wall, hold it against the wall and push it so the screws make a mark in the drywall. Remove the shelf and at those marks, predrill the screw holes through the drywall and into your crossmember. Now put the shelf against the wall again and drive in the screws so they are countersunk about 1/8" or more. Check for level. Now plug the screw holes with pieces of 3/8" dowel or some decorative plugs. As for the finishing work on the drywall, you can get a book at any homecenter that tells how to do that.