Fermentation Room Vs Walking Space

I am setting up a new bakery and I am trying to calculate the ferm room space vs walk in space?
this is an impossibly hard question to answer as I do not know about the production schedule or number of people that I am going to hire initally and if I want to have night shifts. So Retarter is important but so does a fermentation room specially for laminated and enriched doughs. Sourdough bread, i can easly controll buy moving it by the decks and stuff but croissants are a different ball game

I can not really guess how much retarting I am going to do and how much I am going to ferment and bake the same day. 

Would you have the same size of walk-ins as fermentation room or would you have bigger fermentation room than walk-in or other way around 

I am going to produce laminated stuff as bread. 

PS: Fermentation room is an actuall room with humidity and temp control and not proofer/retarder closet. 

Right now I can put int 12 fullsheet racks in each. Quesition is basically should I make 16-8 instead of 12-12 in each room. 

12-12 rack in reach just seams better in terms of flexability. 

Thanks