10
7. Recommended Locations for Smoke Alarms
 • Locate smoke alarms in all sleeping areas. Try to monitor the exit path as the bedrooms are usually farthest 
from the exit. If more than one sleeping area exists, locate additional alarms in each sleeping area.
 • Locate additional alarms to monitor any stairway as stairways act like chimneys for smoke and heat.
 • Locate at least one alarm on every floor level.
 • Locate an alarm in every bedroom.
 • Locate an alarm in every room where electrical appliances are operated (i.e. portable heaters or humidifiers).
 • Locate an alarm in every room where someone sleeps with the door closed. The closed door may 
prevent an alarm not located in that room from waking the sleeper.
 • Smoke, heat, and combustion products rise to the ceiling and spread horizontally. Mounting the 
smoke alarm on the ceiling in the center of the room places it closest to all points in the room. Ceiling 
mounting is preferred in ordinary residential construction.
ANYWHERE ALONG 
THIS BOLD SURFACE
Locations permitted for smoke
alarms and smoke detectors
on tray-shaped ceilings.
(4")
(4")
10 cm
(12")
30.5 
cm
(12")
30.5 cm
(3')
0.9 m
(3')
0.9 m
(3')
0.9 m
ANYWHERE ALONG 
THIS BOLD SURFACE
Locations permitted for smoke
alarms and smoke detectors
on tray-shaped ceilings.
(4")
10 cm
(4")
10 cm
(12")
30.5 cm
(12")
30.5 cm
(3')
0.9 m
(3')
0.9 m
(3')
0.9 m
ANYWHERE ALONG 
THIS BOLD SURFACE
Locations permitted for smoke
alarms and smoke detectors
on tray-shaped ceilings.
(4")
10 cm
(4")
10 cm
(12")
30.5 cm
(12")
30.5 cm
(3')
0.9 m
(3')
0.9 m
ANYWHERE ALONG 
THIS BOLD SURFACE
Locations permitted for smoke
alarms and smoke detectors
on tray-shaped ceilings.
(4")
10 cm
(4")
10 cm
(12")
30.5 cm
(12")
30.5 cm
(3')
0.9 m
(3')
0.9 m
(3')
0.9 m
ANYWHERE ALONG 
THIS BOLD SURFACE
Locations permitted for smoke
alarms and smoke detectors
on tray-shaped ceilings.
(4")
10 cm
(4")
10 cm
(12")
30.5 cm
(12")
30.5 cm
(3')
0.9 m
(3')
0.9 m
(3')
0.9 m
ANYWHERE ALONG 
THIS BOLD SURFACE
Locations permitted for smoke
alarms and smoke detectors
on tray-shaped ceilings.
(4")
10 cm
(4")
10 cm
(12")
30.5 cm
(12")
30.5 cm
(3')
0.9 m
(3')
0.9 m
(3')
0.9 m
NFPA 72 states: “Smoke alarms in rooms with 
ceiling slopes greater than 0.3 m in 2.4 m (1 ft in 
8 ft) horizontally shall be located on the high side 
of the room.” NFPA 72 states: “A row of detectors 
shall be spaced and located within 0.9 m (3 ft) of 
the peak of the ceiling measured horizontally.”
Figure 7-A
Figure 7-B Figure 7-C