We have a project that is going to use a combined approach due to overhangs and the prescriptive calcs not providing enough SF. I have casually measured the spaces and we exceed 20fc. We have one large room that I can easily do a 10 ft grid on, but we also have 10 small offices that are probably narrower than 10ft. How is it recommended that I measure this space? Can I make a smaller grid, so we can include an adequate portion of these offices? Or do I just measure in the corners? (or a set distance off the corners?)