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Guide to Smoke Detector Installation and Placement

Dec 28, 2022|

As a homeowner, fire safety should be at the top of your home security list. Hopefully, a home fire never happens, but it’s important to make sure you have all the right equipment to keep you and your family safe if it does.

Every second counts when there’s a fire in your home. The best smoke detector will help you and your family react quickly to the emergency and give you the best chance of getting out unharmed.

Your smoke detector needs to be placed and installed properly to be effective. In this guide, we explain how a professional goes about the smoke alarm installation process and where they’ll suggest placing detectors in your home.

Vivint Smoke and CO Detector.

Can you install smoke detectors yourself?

If you’re not an expert with electrical wiring systems, you’re better off getting an electrician to install your fire alarm system. An installation specialist will make sure your smoke detector is installed correctly and follows the manufacturer’s instructions, giving you the maximum protection possible.

That’s why Vivint offers professional installation for our combo smoke and carbon monoxide detector and other smart devices. Your installation professional will be able to connect your smart smoke detectors to your Wi-Fi network so they work with your other smart devices.

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How a professional installs a hardwired smoke detector

There are different types of smoke alarms, and they can either be battery-powered or hardwired.

There are a few advantages to having hardwired detectors. They connect to the rest of the smoke alarms in your home — if one senses smoke, they all ring out — and they use your home’s electrical network as a power source. You don’t have to worry about changing their batteries or hear the chirping alarm sound that battery-powered models give off when they’re running out of energy.

The downside is that hardwired detectors won’t work during a power outage. However, some models have a battery backup system that allows them to function during a power surge. Hardwired units are also more difficult to install than battery-powered smoke detectors. Your installer will have to connect them to your home’s electrical system.

Installing hardwired smoke detectors is pretty complicated. Here’s the process an expert will follow to install your detectors.

Important: The first thing an installer should do is turn off power to the breaker panel before getting started and double-check that it’s off with a circuit tester!

Step 1: Place and install remodeling boxes

Your expert will need to place a remodeling box where your smoke detector will be. A remodeling box is simply an electrical box that’s inserted into drywall. Generally, your detector should be situated on your ceiling or about a foot down from your ceiling on your wall.

Your installer will use a stud finder to find out where the studs in the drywall are. Using a level and a marking tool, they’ll trace a straight outline of your remodeling box on the drywall and drill a pilot hole in the corner.

With a drywall saw, they’ll cut out the outline using the pilot hole as a starting point and place the remodeling box in the hole to see if it fits. The fit should be snug, but not to the point where the box needs to be jammed in for it to fit. If multiple detectors are being installed, similar holes will need to be cut for each detector location.

Next, your installer will set up your wiring, but they won’t configure it just yet. They’ll use some 14/2 NM wire (a 14/2 cable has a sheath, two wires, and a ground wire). They’ll run the wire from your home’s breaker box to the nearest smoke alarm location without connecting the cable to the breaker box and tug around 10 inches of wire through the hole.

If they’re setting up multiple detectors, they’ll run wiring from the first alarm location to the second and the second to the third, pulling out roughly 10 inches of cable through each hole. They’ll keep going until they’ve reached every smoke alarm site. When they’re done, all your smoke alarm locations should be connected by wire.

With wire strippers, they’ll remove the shearing from the NM wire, position the hanging wire into the back of the remodeling box, and place the box into the hole in your wall. They’ll tighten the clamping tabs to tighten the box to the wall, locate the copper ground wires and secure them to the remodeling box using a ground screw. Some boxes have clamps to use instead of a ground screw.

Step 2: Wire the remodeling boxes

It’s time to connect your wiring. Your installer will remove about three-fourths of an inch of insulation from the ends of the wires with wire strippers and attach the wires to a 120-volt wire harness. Many smoke detector models have their own harnesses.

They’ll fasten the NM wire (that has just been stripped) to the harness wires (with matching colors) using wire nuts. White wires connect to white wires and red wires connect to red wires. Wires of different colors should never be connected.

Each smoke detector location should have a wire harness. The harness should connect the wires from the breaker box to the smoke detector, and the wires that run from smoke detector to smoke detector. For safety, your installer will tie some electrical tape around the wire connectors.

Any extra wire and the wire connectors will be slipped into the remodeling box, but the plug end of the wire harness should be left hanging out.

Step 3: Connect the smoke detector

Now, your installer can install your smoke detector. They’ll pull the wire harness through the alarm’s mounting plate and line up the mounting plate’s screw holes with the remodel box’s screw holes.

The wire connection should still be hanging out of the mounting plate. They’ll screw the mounting plate to the remodeling box (screws should be included with the system) and attach the wire harness plug to the back of your smoke detector.

If your hardwired detector has a battery backup, they’ll open the battery compartment, place the battery inside, and secure the battery compartment. Most systems use 9-volt batteries. Then, they’ll attach the front of your smoke alarm to the mounting plate (it should twist into place) and make sure the smoke alarm fits snugly.

The only thing left to do is to connect the NM wires to the actual breaker box. Your installer will make sure the circuit power is off before attempting this step.

Step 4: Test the smoke detector

When your smoke detectors are wired to the breaker panel and each other, your installer can activate the power to the circuit on your breaker box. If your alarm has a power light, it should be lit up.

They’ll hold down the test button on each alarm. A loud siren should be heard when the tester is pressed. If the alarm doesn’t sound, they’ll shut off the power to the circuit on your breaker box and make sure all the cables are properly attached. If there are no wiring issues, the alarm is likely defective and needs to be replaced.

Where to place smoke detectors in your home

If you’re curious about where your smoke alarms should be placed, follow the National Fire Protection Association (NFPA) guidelines. Here are some of their recommendations:

  • Homes with multiple floors should have at least one smoke detector on every level, including the basement. If there are no bedrooms on a level, the detector should be near the stairwell.
  • Every bedroom should contain a smoke detector, and there should be another smoke detector right outside each sleeping area.
  • For maximum safety, all your smoke detectors must interconnect.
  • Smoke detectors should be on the ceiling or high on walls. Basement detectors should always be on the ceiling.
  • Alarms should be at least 10 feet away from the kitchen to reduce false alarms.
  • Don’t place alarms close to windows or ducts. Wind can affect their sensors.
  • People with hearing impairments should use smoke alarms with visual cues, like strobe lights. They should also use alarms that shake their bed to ensure they wake up during an emergency.

Correct height placement of smoke detectors

Smoke rises, so smoke detectors must be mounted high (either on the ceiling or on the wall no more than a foot below the ceiling). Smoke alarms in basements always need to be on the ceiling. Homes with pitched roofs should place their detectors in the slope of the roof no more than 3 feet away from the top, but not in the actual peak.

Vivint smoke and CO detector in kitchen.

Keep your home safe with Vivint safety alarms

If you’re looking for the most reliable smoke alarms for your home, consider smart detectors like Vivint’s combination smoke and carbon monoxide detector.

Vivint’s safety alarms work with the rest of your smart home security system, so you can do things like program your smart locks to unlock when your alarm goes off so your family can get out of the house.

Our smart detector will notify you immediately whenever it senses smoke or poisonous gas in your home so you can call 911. Or you can sign up for professional monitoring, and our team will keep an eye on your system and call the fire department if things go wrong.

And with a five-year battery plus backup, you get peace of mind that your smoke alarm is on when you need it most.

See how our experts can professionally install and help you get the most out of your home security system today. Give us a call at 855.822.1220 today.

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