Single Family Homes are 'R-3'.
Condo's, Townhouses are considered 'R-3'
and Highrise Condo's are typically 'R-2'
[F] 907.2.10.1.2 Groups R-2, R-3, R-4 and I-1.
Single-or multiple-station smoke alarms shall be
installed and maintained in Groups R-2, R-3, R-4 and
I-1, regardless of occupant load at all of the following
1. On the ceiling or wall outside of each separate
sleeping area in the immediate vicinity of bed
2. In each room used for sleeping purposes.
3. In each story within a dwelling unit, including
basements but not including crawl spaces and
uninhabitable attics. In dwellings or dwelling
units with split levels and without an intervening
door between the adjacent levels, a smoke alarm
installed on the upper level shall suffice for the
adjacent lower level provided that the lower
level is less than one full story below the upper
[F] 907.2.10.3 Interconnection. Where more than one
smoke alarm is required to be installed within an individ ual
dwelling unit in Group R-2, R-3 or R-4, or within an
individual dwelling unit or sleeping unit in Group R-1,
the smoke alarms shall be interconnected in such a man
ner that the activation of one alarm will activate all of the
alarms in the individual unit. The alarm shall be clearly
audible in all bedrooms over background noise levels
with all intervening doors closed.