How To Install a Smoke Detector

1-2 hours

Learn how to install smoke detectors to keep your home and family safe

A smoke detector should be installed on every level of your home, including basements and one in each bedroom.

If you need to install new smoke detectors in your home, this guide provides easy step-by-step instructions.

For a carbon monoxide alarm installation, see our How To Install a Carbon Monoxide Detector project guide.

WHAT YOU NEED FOR THIS PROJECT

1
Select a location

It’s important that smoke alarms be installed in the proper locations in your home.

Safety: Don’t place smoke detectors over stoves, ovens, clothes dryers or in areas where there is the potential for significant heat or steam generation. Also check with local codes for the number of alarms required for your home and their placement.

2
Choose room-specific alarms

• You can purchase smoke alarms that are specifically designed for different areas of your home.
• Bedroom alarms feature a 10-year lithium ion battery, so you’ll never be awakened by a low-battery chirping sound in the middle of the night. Some units also feature a voice alarm to help raise you from your sleep.
• Kitchen-specific alarms can detect both smoke and carbon monoxide, detect real fires faster, and trigger fewer nuisance alarms.

3
Choose the right placement for detectors

• Smoke rises, so the ideal location for a detector is on the ceiling. Mounting it in the center of the ceiling is best. If it needs to be mounted elsewhere on the ceiling, it must be at least 4 inches from a wall.
• Avoid corners where the walls meet the ceiling and where pockets of dead air sometimes form, preventing rising smoke from reaching the detector.
• Wall-mounted detectors must be installed at least 4 inches from the ceiling to avoid this dead air zone.
• If you have vaulted ceilings, dead air can also form at the apex. Install the alarm at least 4 inches from the peak.

4
Smoke detector installation

• Most smoke alarms come with a mounting base that separates from the alarm itself. This base will have key-shaped screw holes to allow you to fasten the base to a wall or ceiling. Once you’ve determined the location for your alarm:
• Select a drill bit slightly smaller than the size of the supplied wall anchors to ensure a snug fit.
• Use the mounting base to mark the screw holes on the ceiling or wall and drill holes where marked.
• Tap the plastic screw anchors provided into the drilled holes with a hammer.
• Drive the supplied screws partially into the ceiling or wall and line up the mounting base with these screws.
• Place and twist the smoke detector into position under the screws, tighten with a screwdriver, and mount the smoke alarm onto the base.

5
Maintaining your smoke detectors

• Test your smoke alarms at least once a month. On most units, this only requires the push of a button to test that the alarm sounds and the batteries are still working.
• Change the batteries twice a year, even if you’re not hearing warning beeps. If you have a lithium ion battery model, change the batteries every 10 years or so.
• Clean each alarm with a vacuum once a year to remove any dust or particles that may have accumulated in the unit.
• Check the manufacture date on each unit periodically and replace them once they reach their expiration date.