Wow.
Mine is only 8' x 9', but that's still bigger than any non-shared darkroom space I've ever been able to use. Wet side is a 42 inch (I think) standard countertop installed on a 36" base cabinet, with a half inch of slope down to the 24" laundry tub sink, and the joint caulked up with RTV silicone (couldn't get standard counter with a raised lip on the edge, but I'll run a bead of silicone along there if I find it's needed). Dry side will have a pair of kitchen carts, one for each enlarger, that I can roll out to access the doors (paper safes, lenses, negative holders, etc. will be stored beneath each). I may have to get creative mounting the power supply and controller for the color head, but I haven't even unboxed that enlarger yet (arrived last week, 30th). Between the enlargers, I'll have either a counter-top cabinet, or a counter-top cart for dry side counter space, and storage underneath, and I've reserved space with an outlet for a print drying cabinet (which I'll probably have to build, even $700 for a bottom end commercial one is a bit much after paying for the construction work). Meantime, film and prints will hang on a "clothesline".