(A) Fire-warning equipment for dwelling units shall provide a sound that is audible in all occupiable dwelling areas.
(B) Where more than one smoke or heat alarm is installed for new construction, they shall be arranged so that the operation of any smoke or heat alarm causes the alarm in all smoke and heat alarms within the dwelling unit to sound.
However, note that it doesn't specificaly say wired together, could be the use of a relay(s) and multiple circuits.
My local building code requires multi station smokes 120V with 9V battery backup and installed at each living level and in each bedroom. These detectors are further required to be interconnected as Roger mentioned from NFPA 72. We adopted this current Code in 97 (I think)and the NFPA 72 requirement for interconnected Detectors was applicable for new construction for a considerable time before that
Here in VA there is a statewide code that all levels have a smoke detector and that there be a smoke detector in every sleeping room and one outside the sleeping rooms and that they all be powered from the house power and all have battery backup and they all be inter-connected. Except, the state code also says we don't have to interconnect them on remodeling projects where the drywall is not removed and there is no path to inter-connect them. In that case, we are supposed to install them, but not interconnect the ones that can't be wired.
To add to cpals statement, in MA "All power for AC powered smoke detectors shall be taken from a single branch circuit which also provides other electrical service to habitable occupiable spaces." The smoke detector installation requirements apply to new construction, substantial renovations, or if you add a bedroom. Greg you should do some reasearch as to what is required in your area.
Re: Smoke Detectors#154312 02/06/0509:49 AM02/06/0509:49 AM