manufacturers will recommend 10x10' per 1000watts, but I'd cut that back. I prefer to run 1000w per 10x7 with a 6' light mover + or - depending on variables. Larger reflectors (like the sulight supply 'Vertizontal') will allow you to inncrease your footprint. Stationary lighting for me would be about 8x8' absolute max. I'd rather have them too close than too far as long as adequate ventilation is available.
That big of a flowering room is kind of crazy unless you're commercial. With the right method a 10x10 flowering area could produce a pound every couple of weeks. I don't know any smoker who needs more than that.
When they make it legal in my state I would like to become a producer for the dispensaries. Each 14X14 room will be broken up into 3 rooms. 10X14 for flowering and a 4X7 for Cloning and Veg. The left over space will be used for Spare Parts and Nutes.