I think the question is how you get 8 square feet of space out of one plant. Even screened, you shouldn't be taking up that much room. If it were me, and I had only one plant and--I'm guessing here--you have some sort of height issue in your cabinet, I'd LST. For one plant, 12 26 watt bulbs is overkill unless it's a monster plant for an indoor grow (as in 5 ft. +). A "normal" indoor plant that's 2.5 to 3.5 feet high can be flowered quite well with 4 or 5 26 watt CFLs. A plant that size usually takes up about 15" x 15" of space...that's about 1.5 sq. ft., more or less.

Anyway, I'd like to hear some more details. How long has you plant been in veg? How tall is it now? I'm just trying to picture a single indoor plant taking up eight square feet of space....