shelf brackets and steel girder strip

OK metal shelf brackets are gaining popularity for around-the walls layouts, but I combined them with long steel girders to span one wall that was all window.

I use adjustable wall-mounted Bohnacker shelf brackets, the kind with a double-row of mounting holes on the wall-strip. One wall was all window, so on the walls each side of it, the brackets point at each other and have two steel L-girder strips bolted to them to support the layout. the lower deck has a central leg midway, part of a shelving system below it. the upper deck has no support. I wouldn't walk on it but I've sprawled across it to work at the back.