Which way do shelf brackets go?

[Wade Lippman]

I am putting up 15.5" shelves. I am planning on using 15"x12" shelf brackets. Which part goes under the shelf and which on the wall. For 45 years I have done half one way and half the other, so at least I am half right. Thought it might be time to ask. Anyone?

The shelves are replacing a recycled kitchen cabinet that has been on the wall for 16 years. Today the particleboard on the back disintegrated and the cabinet fell. Go figure.

[Jim Koepke]

My opinion might be wrong but it has always been to put the long arm down.

jtk

[Bill Dufour]

My opinion might be wrong but it has always been to put the long arm down.

jtk


Correct. It is simple physics.
Bill D

[Roger Feeley]

I don’t think the length of the arm going down is important. All of the stress on a shelf bracket are on the two upper screws driven into the wall. The shelf wants to fall down but can’t so it tries to pull away from the wall. The screws into the shelf don’t have much to do other than keeping the shelf from shifting. The bottom screw into the wall doesn’t much to do other than keep the bracket from rotating. Those two top screws are the workhorses. Make them long and drive them into studs.

[roger wiegand]

Whichever way they fit/look best. I suspect they come with different length arms to accommodate different shelf widths.

There are plenty of symmetrical brackets available that eliminate the issue.

[Jim Koepke]

This is where Dr. Google is your friend:

479593

If my understanding the "three quarters rule" is correct this means the 12" length of "the actual bracket under the shelf" means it would be good for a 16" deep shelf.

jtk

[Kev Williams]

When I put shelves up, while I do put the long side down I never put in the bottom screws, just 2 more screws to remove and holes to fix later if/when the shelf goes away.

And 'floating' glass shelves seem to work fine without much in the way of legs--
479594

[Charlie Velasquez]

This question was asked by a Home Depot customer who wanted to use a 12”x 8” shelf bracket.
This is the reply by the manufacturer.

The other thumbnail is of a closet rod/shelf bracket that will support up to 500 lbs. of clothing and stuff.
The shelf leg is 14”, the wall leg is 9”.

[andy bessette]

Shelf brackets can be installed either way; depends on the application.

https://i.postimg.cc/mrLzkjmd/shopping.webp (https://postimages.org/)

[Jim Becker]

I agree with Andy...I'd choose the long leg vertical for more weight under a narrower shelf and short leg vertical for a wider shelf for bigger bulk understanding the weight to be supported might be a little less. Those brackets he shows as an example are pretty darn good, too. I've used a bunch of those for shop purposes.

[Anuj Prateek]

I have always installed them both ways based on shelf width. I don't think it really matters for practical purposes which side is down.