Safety Tools

Interconnected Or Stand Alone Smoke detectors?

Are you having problems deciding whether to install an interconnected smoke detector or a stand-alone smoke detector? Look no further. This guide aims to show you which you should go for. So seat down, and read through this review keenly.


A smoke detector is a device that senses smoke, typically as an indicator of fire. Commercial smoke detectors issue a signal to a fire alarm control panel as part of a fire alarm system, while household smoke detectors, also known as smoke alarms, generally issue an audible or visual alarm from the detector itself or several detectors if there are multiple smoke detectors interlinked.

Smoke detectors are housed in plastic enclosures, typically shaped like a disk about 150 millimeters (6 in) in diameter and 25 millimeters (1 in) thick, but shape and size vary. Smoke can be detected either optically (photoelectric) or by physical process (ionization). Detectors may use one of the two or both sensing methods.

Sensitive alarms can be used to detect, and deter, people smoking in areas where smoking is banned. Smoke detectors in large commercial and industrial buildings are usually connected to a central fire alarm system.

Domestic smoke detectors range from individual battery-powered units to several interlinked units with battery backup. With interlinked units, if any of them detects smoke, all of the alarms will trigger even if household power has gone out.

The risk of dying in a home fire is cut in half in homes with working smoke alarms. The US National Fire Protection Association reports 0.53 deaths per 100 fires in homes with working smoke alarms compared to 1.18 deaths without (2009–2013). Some homes do not have any smoke alarms and some homes do not have any working batteries in their smoke alarms.

Installation and placement of smoke detectors

In the United States, most state and local laws regarding the required number and placement of smoke detectors are based upon standards established in NFPA 72, National Fire Alarm and Signaling Code. Laws governing the installation of smoke detectors vary depending on the locality.

However, some rules and guidelines for existing homes are relatively consistent throughout the developed world. For example, Canada and Australia require a building to have a working smoke detector on every level.

The United States NFPA code cited in the previous paragraph requires smoke detectors on every habitable level and within the vicinity of all bedrooms. Habitable levels include attics that are tall enough to allow access. Many other countries have comparable requirements.

In new construction, minimum requirements are typically more stringent. All smoke detectors must be hooked directly to the electrical wiring, be interconnected, and have a battery backup. In addition, smoke detectors are required either inside or outside every bedroom, depending on local codes.

Smoke detectors on the outside will detect fires more quickly, assuming the fire does not begin in the bedroom, but the sound of the alarm will be reduced and may not wake some people. Some areas also require smoke detectors in stairways, main hallways, and garages.

A dozen or more detectors may be connected via wiring or wirelessly such that if one detects smoke, the alarms will sound on all the detectors in the network, improving the likelihood that occupants will be alerted even if smoke is detected far from their location. Wired interconnection is more practical in new construction than for existing buildings.

In the UK the installation of smoke alarms in new builds must comply with British Standard BS5839 pt6. BS 5839: Pt.6: 2004 recommends that a new-build property consisting of no more than 3 floors (less than 200 square meters per floor) should be fitted with a Grade D, LD2 system.

Building Regulations in England, Wales, and Scotland recommend that BS 5839: Pt.6 should be followed, but as a minimum a Grade D, LD3 system should be installed. Building Regulations in Northern Ireland require a Grade D, LD2 system to be installed, with smoke alarms fitted in the escape routes and the main living room and a heat alarm in the kitchen; this standard also requires all detectors to have a mains supply and a battery back up.

Keep Smoke Detectors Working Properly

Find important information and tips for keeping your smoke detectors working properly below:

  • Test your smoke detectors at least once a month by using the detectors’ test button.
  • Replace the batteries in your smoke detectors regularly, or as soon as it chirps, warning that the battery is low (Reminder: “Change your clocks, change your batteries!”).
  • Regularly vacuuming or dusting your smoke detectors and following manufacturer instructions can help keep them working properly.
  • Replace your smoke detectors every 10 years.
  • Never borrow a battery from a smoke detector.
  • Make sure that everyone in your home can hear and recognize the alarm sound your detector(s) makes and how to react immediately.

You should note that smoke detectors can be further divided into two:


These detectors can easily have defective or worn-out batteries and need to be checked monthly. You never want to put old batteries into your fire alarms or smoke detectors.

You will want to frequently check that the batteries are working properly.


These detectors are powered by your home’s electrical system but tend to also have backup batteries so they still work if there is a power outage. Even though this device mainly uses your home’s electricity, you still need to check the batteries.

Hardwired smoke detectors still need to be tested monthly. This helps ensure that both the parts and batteries are working properly

What is an Interconnected Smoke Detector?

A hardwired smoke detector can communicate wirelessly with other compatible alarms to create a fire alarm system (additional alarms sold separately). When one alarm is triggered, all connected alarms will sound

Integrated battery backup allows continuous detection during power outages.

Benefits of Interconnected Smoke Detectors

When smoke and carbon monoxide (CO) alarms are interconnected, each alarm can now tell you when there’s smoke or carbon monoxide in any room that has a smoke/CO alarm. A traditional alarm can alert you to the presence of smoke, fire, or carbon monoxide, but it can only detect the area around it.

  • Interconnected alarms are safer

Interconnected smoke alarms are safer than standalone smoke alarms because they let you know about an emergency sooner. Even if you’re in the house, you may not be close to the area where the fire started. If you’re in the basement, you may not hear an alarm in the bedroom. According to the National Fire Protection Association (NFPA), the majority of fatalities from US home fires were located in a different room than where the fire started.

  • Required for new home constructions

Because of their many benefits, including safety and early warning, many states now require interconnected smoke alarms for new home construction.

  • Wireless Interconnect

In the past, interconnection had to be hard-wired between smoke/carbon monoxide alarms. Now smoke/CO alarms can be interconnected wirelessly, without requiring expensive retrofits. With wireless interconnect, you can easily retrofit existing homes and get them up to code.

  • Full Home Coverage

When it comes to staying safe from home fires, time is of the essence, with only a couple of minutes to escape from a house fire. If a fire starts on the top floor of your home and you are in the basement, there’s a chance you may not be able to hear the alarm going off.

If you have an interlinked smoke alarm system in your home, the basement smoke alarm will sound when the top floor alarm goes off.

You will be able to hear the alarm regardless of where you are, compared to where the initial alarm is. In fact, according to the National Fire Protection Association (NFPA), the majority of fatalities stemming from home fires in the United States were located in a different room than where the fire started.

An interconnected smoke alarm system will help give you and your family peace of mind knowing your entire house is fully protected.

A survey was carried out, on whether smoke detectors improve safety:

Interconnected smoke alarms increase safety;

In a Consumer Product Safety Commission (CPSC) survey of households with any fires, including fires in which the fire department was not called, interconnected smoke alarms were more likely to operate and alert occupants to a fire.1 People may know about a fire without hearing a smoke alarm.

  • When smoke alarms (interconnected or not) were on all floors, they sounded in 37% of fires and alerted occupants in 15%.
  • When smoke alarms were not on all floors, they sounded in only 4% of the fires and alerted occupants in only 2%.
  • In homes that had interconnected smoke alarms, the alarms sounded in half (53%) of the fires and alerted people in one-quarter (26%) of the fires.


Above all, you should own at least one smoke detector in your home. However, to be more on the safer side, install an interconnected smoke detector. This will help to inform all the persons in the building when there is smoke. Protect what matters most by installing reliable protection in your home today.