Here is what I found for Massachusetts. This appears to be in the R-2 use group.From the Mass Building code. " 918.4.7 Use group R-2: An automatic fire detection system shall be installed and maintained throught all occupancies in use group R-2 and in accordance with table 918.
Exceptions: 1. an automatic fire detection system is not required in buildings that do not have interior corridors serving guest rooms or dwelling units and where all guest rooms or dwelling units have a means of egress door opening directly to an exterior exit access which leads directly to the exits. 2. System smoke detectors are not required in guestrooms or dwelling units. 3. A system heat detector shall be required within each guest room or dwelling unit located not more than six feet from each door way that leads to an interioir corridor or exit. System heat detectors shall not be required where the guestroom or dwelling unit is equipped with residantial sprinklers that, when activated will activate the fire protective signaling system."
This is what I thought the rules were and looking it up confirmed. Sounds like the town is mixing up their multi unit dwelling code witht the single and two family code.
Even in a two family each apartments smokes are not interconnected with each other.
