NFPA 72, Fire Alarm Code
11.5.1.1 Smoke Detection. Where required by applicable laws, codes, or standards for the
specified occupancy, approved single- and multiple-station smoke alarms shall be installed as follows:
(1) In all sleeping rooms
Exception: Smoke alarms shall not be required in sleeping rooms in existing one- and two family dwelling units.
(2) Outside of each separate sleeping area, in the immediate vicinity of the sleeping rooms
(3) On each level of the dwelling unit, including basements
Exception: In existing one- and two-family dwelling units, approved smoke alarms powered
by batteries shall be permitted.
Commentary:
Although not required for existing construction, it is recommended that smoke alarms be located in all bedrooms, whether new or existing construction. The minimum siting requirement for existing construction is for a smoke alarm outside each separate sleeping area and on every level of the dwelling. This requirement can be met using multiple-station smoke alarms. In new construction, smoke alarms are required in each sleeping room as well as outside each separate sleeping area and on every level of the dwelling.
See Exhibit 11.3 for a typical multiple-station smoke alarm arrangement.