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I'm planning on installing Ikea shelves mounted on wall brackets (using the Antonius system). Until recently there were Antonius shelves 14 3/8 inches deep, but now they've disappeared, leaving only 11 inches deep shelves. There is a 14 3/8 deep shelf (a Broder shelf), but to attached to the wall mount I need brackets. There are only brackets for 11 inch shelves. The shelves are planned to store dry food stuff mostly (cans, pasta, rice, potatoes, etc.), so it might be quite heavy.

What is the harm in using shorter brackets with a deeper shelf? The only things I can think of are a reduced carrying capacity for the bracket and since the out edge of the shelf is not supported, it might be break. But how realistic is that the 3 3/8 edge will break from a static load? The deeper shelf is wood (as opposed to particle board for the Antonius shelves).

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5 Answers 5

up vote 6 down vote accepted

A wooden shelf that is cantilevered 3 inches or so out from the end of a bracket will probably survive some load. But stack too much of a load on it (a pantry, canned food is heavy!) and even wood will crack. Particle board is very likely to fail of course as it has very little real strength.

A shorter bracket will often be designed for a smaller load. (Long brackets may be wider at the base, to support a larger load. They may be more robust to prevent buckling.) The issue is not just will it support the entire width of the board, but is the bracket adequate to support a greater load since a wide shelf will have more items stored on it. Those extra items stored are hanging a significant distance away from the wall.

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This all confirms my suspicion that it will probably be okay, but it would be better to look for a more adequate hanging system. I think this answers my question best. –  Eli Iser Sep 4 '12 at 13:27

The product you are looking for are brackets for what is called "standards". They come in many different sizes. Ikea likes to put fancy names on things so they can charge more. Just goto your local home improvement store/hardware store and tell the person there that you are looking for brackets to fit standards.

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This might be true in the US, but here the large home improvement stores are notoriously expensive. The idea behind using Ikea is to have everything in one place, but I'll look around, thanks. –  Eli Iser Sep 4 '12 at 5:38

If the shelf you're putting up is a solid wood shelf and not particle board, an 11" bracket will be fine (assuming it's a metal bracket). Certainly it's not ideal, but I don't know what you have for hardware stores in Israel. The grain of the wood will be perpendicular to the brackets, which would give you a chance to break the wood out at the end, but how much weight can you really put on the last 3 3/8"?

However, you have one big unanswered question. You haven't mentioned what you're attaching the brackets to. Are your walls drywall? If so, can you sink both brackets into studs behind the drywall? If you can, no worries about weight, if you can't hit then most anchor systems are going to be rated for 75-125 lbs(about 34-57 kilograms) for 5/8" drywall (1.5cm). If you put several anchors into the wall for each rail, you'll have plenty of weight bearing capability.

If your walls are a concrete block (like many student dormitories here in the U.S.) you'll be fine. Same with a wood finished wall (such as v-match pine). If you have some kind of paneling, you'll want to anchor directly to studs behind. Good luck!

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Walls in Israel are most often masonry, and that's the case for me - both walls I'm planning on using are concrete, so no worries about weight capacity. –  Eli Iser Sep 4 '12 at 5:35

Use the Broder brackets. They were designed for the Broder shelves.

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Hmm... it looks like Ikea Israel doesn't carry Broder wall uprights, and the Broder fittings are much more expensive than Antonius (although in the US they cost less...). From the pictures it is difficult to say if a Broder bracket will fit an Antonius wall upright... –  Eli Iser Sep 3 '12 at 11:07
    
If you are going in person, you can always try them out. I've mixed and matched uprights and brackets from Lowes before. I ended up using name brand uprights and generic brackets I believe, or vice versa. –  Zach Sep 17 '12 at 15:55

The links you provide no longer work. To answer your question though, "yes and no" the brackets for the 11" shelves would work up to a point. I am assuming that since you said brackets for 11" shelves, that means the brackets are "designed" for 11" shelves and that they in themselves are not 11" long. Using the brackets would change the load they could carry. Also where the load is place will be become a more important factor at play.

There are two basic forces at play in a bracket system. There is the straight downward force that is normally called the shear force. Then there is the moment forces, which is more of turning/twisting force. When a bracket extends to edge of the shelf then the shelf itself and it's load can be treated as having a well established load limit. The max load for bending moment would be as if all the weight it focused on the tip of the bracket. The maximum shear force would be at the bracket base (thus why brackets are larger at the base). Things become more complicated as the shelf extends beyond the end of the bracket. A second bending moment/point is created between the shelf and the bracket. So it is important to know if the bracket is attached to the shelf as this will cause it to act in many respects as one unit. Even if it acts as one unit, as correctly mentioned above a second shear point is created at the edge of the bracket and the shelf.

Since I don't know the exact numbers (such as load metal thickness etc) the best i can do is point you to some sources that can help you solve the matter.

Here is the technical consideration of MDF and composite shelf.

I have listed a few tools that can help you determine the width span and sizing of the shelves:

  1. The Sagulator Even with correct brackets make sure it doesn't sag! Remember edgeband (or using a strip of wood on the edge of the shelf) can have a large impact on the load capability.

  2. Beam Formulas (PDF, page 9)

  3. Bending Moment Diagrams

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