I have them all over my shop, well on three walls anyway. Four of them are
9' long and 1 is 10' long. The uprights are 24" deep and the Galvanized tops are 26" deep. There are also some galvanized lower shelves.
They don't go all the way up against the wall due to the one row of blocks, but that's fine with me. It allowed me to use the 28" deep blueprint file cabinets under one of them without sticking out past the front. Of course you can get them whatever height you want, and then if you don't like it you could cut them down, or raise them. I have 4x4's under the uprights of mine, but I'm wanting to put 4x6's to raise them slightly plus it will give me a bit more room under the bottom.
I've had them in many different configurations over the years until I got them where they're at right now. Seems every time I drug something in I was rearranging trying to make more room or better use of my space anyway.
I'm really to the point now where I can't get much else in, in fact the last time I tried to re-arrange I ended up putting it back the way I had it before. It's past time to move and build a bigger/better shop.
Sorry for a couple of the pictures, but if you look past the press, and past the mill to the walls you can see the other racks full of stuff and in different configurations.
Welcome to the forum BTW.