Urban Gardens. What a cool ideal. I love the efficient use of space. Don't know if I would have enough space to build this, (due to my small yard and other future plans) but if I do I would probably partial enclose it with plexi-glass windows with a frosted treatment. So I could choose to have the windows closed or open (we get lots of mosquitoes here in MN). I like the railing around the top. I would feel scared that people would fall otherwise. I would probably make them even higher just in case. I would also use cedar for the wood and paint it with an outdoor paint to make sure it would last for a long time. I would also put pavers down for the floor and add an outdoor rug. A girl can dream huh?