Smoke Detectors Installation

Smoke detectors are a critical component of keeping your family safe. They should be installed on each level of your home and outside sleeping areas. Hardwired detectors require creating a new circuit in your electrical service panel, so homeowners who aren’t comfortable doing this work should have an electrician perform the project.Smoke Detectors

Smoke detectors are usually located on the ceiling and outside bedrooms, but they should also be in some hallways and rooms used for cooking or smoking. A smoke detector is especially important in the kitchen because a fire can spread much faster than a bedroom fire. For professional installation services, call Electrician West Palm Beach now!

Occupants are often unaware of a fire in the bedroom while asleep, but a smoke detector can warn them to escape. The NFPA recommends installing one alarm in every bedroom and inside any room used for sleeping purposes. Smoke detectors are also required in most jurisdictions on every floor of a dwelling, including basements and habitable attics (but not crawl spaces or uninhabitable attics).

When mounting smoke detectors on the ceiling, they should be placed four to twelve inches away from corners and near the center of the room. This is because smoke rises, and it may not reach a wall-mounted detector that is too far from the ceiling.

The NFPA advises homeowners to choose between ionization or photoelectric detectors, both of which are effective at detecting slow-burning “smoldering” and fast-burning “flaming” fires. However, ionization detectors are less sensitive to dust particles and other contaminants that can trigger false alarms. In order to address this concern, some people opt to install dual-sensor smoke detectors that can sense both ionization and photoelectric emissions.

It is recommended that a smoke detector be installed in each hallway that contains a bedroom and at the end of long hallways. Additionally, a smoke detector should be placed at the top of stairwells so that smoke rising from a stairway cannot be blocked by a closed door or another obstruction.

Smoke detectors should not be located in bathrooms or steamy areas because they will often trigger false alarms due to steam. In addition, they should not be located too close to fans and air vents because they may be unable to detect the presence of smoke that is being blown away from the detector by the strong draft. Instead, smoke detectors should be installed a minimum of six feet from stoves and ovens and three feet from bathroom doors.

Electrical Boxes

The electrician first locates the wall or ceiling openings where each smoke detector will be installed. Then he determines which existing circuit the smoke detectors will plug into and switches off that circuit’s power supply.

He then uses a stud finder to locate the ceiling joist or wall stud at each installation location and creates a cutout in the drywall for each electrical box using that stud finder as a template. Each electrical box is then fastened to the drywall with screws, which draw the retaining tabs up tight against the back of the drywall and secure it in place.

Next, he runs a two-wire NM cable (with ground) from the existing circuit to the first smoke detector box. He also identifies and shuts off the circuit that this smoke detector will be piggybacked onto, which is typically a circuit with lighting.

At each of the other smoke detector locations, he inserts the corresponding old-work electrical boxes into their drywall openings. He feeds the circuit wires through the smoke detector’s mounting plate, aligning the screw holes on the plate with those of the electrical box, and then using the included screws to fasten the plate to the box. He then cuts off the extra cable insulation that protruded through the drywall opening and strips away the outer sheathing with a wire stripper. Approximately 8 inches of wire extends from the cable into each of these electrical boxes, and the installer tucks the excess inside each box.

After the circuit feed wire has been connected to the first smoke detector, the electrician connects the bare copper ground wire to the detector’s mounting bracket and then runs that same cable (with ground) to each of the other smoke detector locations. At each of these locations, the electrician connects the circuit wires to the smoke detector’s mounting plate by feeding them through the hole in the electrical box and then aligning the screw holes on the plate with those of the electrical box. He then cuts off any excess cable and strips away the outer sheathing on each of the remaining circuit wires.


A good number of electrical wiring projects require a professional, but with standard safety precautions and instructions followed, you can wire smoke detectors yourself. The best way to ensure that your hardwired smoke detectors are properly connected is by following the guidelines set forth by the International Residential Code (IRC). This comprehensive compilation of safe building standards requires all homes to have an interconnected fire alarm system in place. It is generally required that the system be upgraded during any major remodeling or additions to a home.

Your electrician will begin by making sure that old electrical ceiling boxes are in the right locations for new smoke detectors. They will also ensure that the electrical box that holds the first smoke detector has a 2-wire cable running into it from its power source. From there, a 3-wire cable will run to the next detector, and so on.

The electrician will then set up the first electrical box by pulling 14/2 NM (a sheathed electrical cable that has two wires and a ground) from its power source to the nearest smoke detector location. They will then draw the wire into the first box, leaving a few inches of extra cable hanging out of the back of the box.

For the remainder of the wire runs, your electrician will follow the same procedure for each of the remaining smoke detectors. They will continue to run the sheathed cable from its power source to the first smoke detector and then, with each additional detector, to the next one, continuing the daisy-chain process until all smoke detectors have been interconnected.

For hardwired smoke detectors, you will want to use sheathed electrical cable that has three wires (hot, neutral, and interconnect). These types of cables are available at most hardware or electrical supply stores. If you are planning to install smoke detectors yourself, it is important that you purchase all the necessary materials before starting so that you don’t get stuck halfway through the project without any needed supplies. It is also a good idea to have all your tools lined up before you start working so that you don’t have to keep stopping to pick up more screws or drill bits.


For safety reasons, it’s a good idea to have smoke detectors that are hardwired rather than battery-powered. These types of devices have an electrical cable that runs unseen behind the ceiling or wall directly into a connection box on the device. This provides continuous power to the device, and if the power fails, an onboard battery takes over and continues to operate the alarms.

To install these types of detectors, first use a stud finder to locate the joists or wall studs where you plan to mount the box. Then cut a hole using a drywall saw and set the remodeling box in the opening to check for a snug fit. If you’re installing multiple boxes, be sure to have a number of similar holes lined up before starting. Then, carefully strip the insulation off the ends of each wire and make a good connection with a screw-in electrical connector. Be careful not to damage the stranded wires, as this can prevent the detectors from operating properly.

When connecting the detectors to their wiring, it’s important to follow the manufacturer’s instructions. Some smoke detectors require a dedicated circuit, while others can be connected to an existing lighting or outlet circuit. If you’re unsure about the installation process, it’s usually best to have a professional electrician complete the work.

The National Fire Protection Association recommends having at least one smoke detector in every sleeping area of your home, as well as outside each bedroom and on each floor of the house, including the basement. In addition, special smoke detectors for the hearing-impaired are available that emit a light instead of an audible alarm.

Despite being a fairly simple project, installing smoke detectors is not something that most homeowners should attempt on their own. This is a task that has the potential to have serious consequences if it’s done incorrectly, so hire a professional electrician if you’re not comfortable with the advanced electrical work involved. Look for a qualified professional who has good ratings on reputable sites and is licensed in your state. Also, ask about a guarantee or warranty that shows they stand behind their work.

Michelle Alphin