I'm a contractor who builds commercial legal grows in California. My personal opinion is that if your going commercial you really should be running Gavita pros, redundant air conditioning systems and CO2 supplementation. Introducing outside air in something this big is a big no-no and air cooled lights should be avoided, even if it is just for the lights housings leak eventually ducting breaks down eventually and leaks can and will happen. Its a cool idea, but they should switch to more efficient lights and a better controlled system. Also anything that large should be on some kind of remote control/dosing system like and Agrowtek or a custom made PLC for the purpose. There are some other benefits to using a larger room, 19'x19' is the most efficient I have worked with. If the room is only 8' wide then you either have a 2' wide walkway in there so you are losing 1/4 of your total square footage to walkways. Or you have some very thin walkway and you make pruning and other work a nightmare for whoever you have doing that work. In a larger room with properly built caster trays you only need a 2' walkway in the entire room and you can just roll your trays out of the way so you can get to any side of any tray you need to.