Selecting a Smoke Alarm

Having the right smoke alarm installed in your home is an essential part of keeping your family safe. Selecting a smoke alarm can be a daunting task, as there are many models with unique features and price points to consider. It's important to understand the differences between each model so you can make an informed decision that meets the needs of your home.

When choosing a smoke alarm for your home, there are a few factors to consider in order to ensure you have the best possible protection. First and foremost, it is important to determine what type of smoke detector is best suited for your needs; ionization or photoelectric alarms each have their own benefits. Secondly, the placement of the smoke detector can be an important factor when it comes to its effectiveness. Finally, one should take into account any special features they might want in their alarm such as voice alerts or wireless connectivity with other alarms in the house.

Ionization detectors tend to respond more quickly to fast-flaming fires while photoelectric ones are better at detecting smoldering fires. Ionization detectors also require battery replacement more frequently than photoelectric ones which may prove costly over time.

Types of Smoke Alarms

Smoke alarms are a must-have in any home as they provide early warning of a potential fire. There are several types of smoke alarms available, each with its own unique features and benefits. Ionisation, optical, combined, and heat alarms are the four main types that homeowners should be aware of when choosing the right one for their property.

Ionisation smoke alarms use radiation to detect small particles generated by smouldering fires. This type is usually the most sensitive to slow-burning materials such as mattresses or upholstery. Optical smoke detectors use photoelectric sensors which respond to larger particles produced by fast-burning fires such as paper or wood. Combined ionisation and optical detectors combine both technologies for greater accuracy when it comes to detecting different types of fire at an earlier stage.

Ionisation Smoke Alarms

The cheapest to purchase, they work by detecting the small particles of smoke produced by flaming fires such as chip pans. They detect this type of fire very quickly before any smoke gets too thick. When faced with a slow-burning or smouldering fire, which will give off larger quantities of smoke before bursting into flame, these units can take marginally longer to activate and can be prone to false alarms when cooking.

Optical Smoke Alarms

A slightly more expensive option but this type of alarm can detect larger particles of smoke which would be produced by such things as a smouldering foam-filled sofa, or overheated electrical cable. They are marginally less sensitive to free-burning flaming fires. These units are less prone to false alarms from cooking fumes.

Combined Smoke Alarms

These detectors are effective at detecting slow-burning as well as flaming fires - which are both common types of fire. Combined smoke alarms are the wave of the future for home safety and security. These combined devices have a number of features that make them more effective than traditional smoke alarms. The combination alarm can detect both heat and smoke, making it more reliable in detecting a fire. It also has a louder siren than other types of smoke alarms, which helps ensure everyone in the house is alerted to danger quickly. In addition to their enhanced detection capabilities, these combined alarms come equipped with other important safety features such as carbon monoxide detectors or voice notifications. This helps homeowners stay informed and alert in case of an emergency situation. Furthermore, many of these newer models come with built-in wireless capability that allows users to monitor their homes remotely via their smartphones or tablets. Combined smoke alarms provide users with greater peace of mind by providing multiple layers of protection against fire danger and other hazards in the home.

Heat Alarms

These alarms are not as likely to cause problems with false alarms as they are not responsive to smoke, fumes, or mist. They are sensitive to heat only and are recommended to be used in conjunction with smoke alarms and should be interconnected. It is recommended that heat alarms be used in kitchens and may also be used in garages or living areas but should not be installed where a fast response to a fire is required.

Should any member of your family suffer from hearing impairment it is possible to obtain an adapted unit suitable for their needs.

How Many Do I need?

Calculating how many smoke alarms you need In an ideal situation, you should install an alarm on each floor. Always ensure your alarms are tested weekly and fully operational and the more alarms you have the safer you will be. If you are only able to site one alarm to serve two floors ensure you are able to hear the audible warning, even when asleep. If you have a computer or TV in a bedroom it would be beneficial to install an additional smoke alarm in that room. Again, ensure it is tested weekly.


Please check our blog post about siting smoke alarms to ensure the best results. Always use a fully qualified electrician.


Choosing the correct battery to use is important. Alkaline This is the cheapest option initially, but these batteries need changing regularly throughout the life of the smoke alarm increasing the overall cost. They can be removed too easily. Lithium Although more expensive the life of a lithium battery is the same as the life of a smoke alarm and, therefore, will not need to be renewed. It cannot be removed from the unit. Once installed, to keep your smoke alarm in good working order, you should:

  • test it once a week, by pressing the test button until the alarm sounds
  • if using an alkaline battery - change it as necessary or at least once a year (unless it's a ten-year lithium battery)
  • replace the whole unit every ten years


When it comes to smoke alarms, their location is just as important as their functionality. In order to maximize safety and ensure that every corner of the home is protected from danger, it is essential to place smoke alarms in the right areas.

First and foremost, all levels of a house should have at least one alarm installed. This means placing them on ceilings or high walls in hallways or other common areas where they can be easily heard. It’s also important to place smoke detectors near sleeping areas so they will wake people up in case of a fire emergency. Additionally, kitchen smoke alarms should be placed at least 10 feet away from cooking appliances like stoves so that nuisance false alarms are avoided due to grease buildup or steam from cooking activities.

Kitchen - Heat detector
Downstairs Hall - Optical
Living Room - Optical
Bedroom - Ionisation
Upstairs Landing - Optical

Linking Smoke Alarms

Smoke alarms can and should be linked together so that when one is activated they all sound. This can be done by cabling or by the use of radio-link bases such as the one below


Smoke alarms are a critical component of home safety, and an essential part of protecting your family from fire. The conclusion is that smoke alarms should be installed in every home, tested regularly, and replaced on a regular basis. It’s also important to have an escape plan in place that all household members are aware of so they can evacuate quickly if needed.

To ensure the maximum protection for your family, it’s recommended to install interconnected smoke detectors on each level of your home, as well as inside bedrooms and other areas where people sleep. Interconnected alarms enhance protection by sending out a loud sound when one detector senses smoke or heat. It’s also important to test the units monthly to make sure they’re working properly.