I am trying to get plans approved for the city of San Diego and I have two, 3 story buildings. Each building is a duplex with the bottom 2 floors being site built and the top (3rd) floor is a factory built modular. I think we should be able to install fire suppression under NFPA 13D and the city is trying to make me install under 13R which is much more expensive . I believe we meet the criteria of 13D as a duplex with manufactured unit. Can anybody help me?