I am enclosing my 25x25 garage and making it into my masterbedroom. I need to make a subfloor and need some direction there. Also, there will be a master bath with garden tub and shower and all amenities. Also, there will be a small study for my computer and stuff. My house is one story brick and there is brick 15" above the concrete foundation. Would an 8" sub floor be sufficient and how is that done. How would I join the sub floor from the bedroom to the bath and study? Help is needed, I do have some construction experience but it has been awhile.