Fire Supression for 2F to 3F conversion

[Mike St. Jean]

I purchased an existing 2 family in an MBTA community under the 3A Zoning Act. The zone I'm in allows for me to file for a special permit to convert to a 3 family. (Finishing out an unfinished basement)

The town has a brand new building commissioner I met with. He told me that under the IBC, I'd be required to add sprinklers throughout the whole house. (I'd likely need to displace the tenants in the existing 2 units)

He said I could file an appeal with the state to just add the necessary fire suppression systems to the basement since the existing 2-family just had its smoke alarm system re-wired. 

I'm trying to do the research and interpret the code on my own, but I'm getting conflicting feedback on the sprinkler issue. I'm wondering if anyone knows of a good architect in Swampscott who understands the current code and zoning and can advise accordingly before I spend a bunch of money on sprinkler systems. TIA