Highlights
Put smoke detectors inside and right outside all bedrooms.
You should also put smoke detectors on every level, including the basement.
Smoke detectors should be placed high on the wall or on the ceiling.
Place them away from drafts and cooking appliances.
Smoke detectors sniff out fires, giving you time to escape and call 911. However, they can’t do their jobs unless they’re installed in the right locations.
To make sure your local electrician properly places these crucial safety devices, check your local building codes and follow these tips.
Pro Tip: Make sure to buy interlinking smoke detectors, which all sound when one identifies smoke or fire. According to HomeAdvisor, an interconnected fire system usually runs $2 to $3 per square foot for new construction and $4 to $12 per square foot for retrofitting an existing building.
Where to Place Smoke Detectors
Ask your local building department for rules specific to your area. At a minimum, though, to comply with NFPA 72, National Fire Alarm and Signaling Code, you need to install smoke detectors:
On each level of your home, including the attic and basement
Inside every bedroom
In all hallways or areas outside bedrooms
In the living room, den, or family room, or near the staircase to the upper level
So, for a three-bedroom ranch house with a basement but no attic, you would need at least five or six smoke alarms. If you have a two-story house with four bedrooms and a basement but no attic, go for at least seven or eight.
Places to Avoid Installing Smoke Detectors
We’ve all broiled steak or baked a pizza just a minute too long, then had to contend with a beeping smoke alarm. Cue the frantic opening of doors and windows.
To avoid false alarms and keep your detectors functioning well, do not install your detector:
Fewer than 20 feet from fuel-burning sources, like stoves, furnaces, water heaters, and space heaters
Fewer than 10 feet from damp, humid places, like bathrooms with showers, saunas, and dishwashers
In areas with temperatures below 40 degrees Fahrenheit or above 100 degrees Fahrenheit, like unfinished attics or basements and outdoor rooms
In very dusty or dirty places, like laundry rooms
In places infested by insects (bugs can clog openings to detector sensing chambers, triggering alarms)
Within 12 inches of fluorescent lights, whose noise can interfere with sensors
Smoke Detector Placement Tips
When installing your smoke detectors, keep these suggestions in mind:
Mount Away from Drafts
Avoid placement near fresh air vents, ceiling fans, heating ducts, doors, or windows. Wind can blow smoke away from smoke detectors, allowing fires to go undetected.
Place High Up
Install on the ceiling or walls within 12 inches of the ceiling (if you have a pitched ceiling, place four inches below the peak). Because smoke rises, you’ll increase the chances that your devices will detect fires, giving you and your family more time to escape in case of emergency. The benefit of avoiding the ceiling is your detectors will be easier to access, if you need to swap them out or replace their batteries.
