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Within the domestic environment, smoke alarm installations are one of the most important.

We have intensive knowledge of all types of smoke alarms and heat alarms and can offer advice as to which heat or smoke alarm is best for your property. Red Electrical can install various brands, however as a part of our product criteria of high quality, proven products, we have preferred suppliers for heat and smoke alarms.

The most commonly used smoke or heat alarms in domestic properties are long-life battery powered mains powered. Another option is to provide a constant 230v supply, which can be from its own designated circuit or from a nearby lighting circuit. Mains powered smoke/heat alarms should be installed by a qualified electrician, with a Certificate of Compliance being issued. This ensures that your smoke alarm installation is safe and effective.

choosing your smoke alarm

Which alarm sensor goes where?

There are many types of fire alarms, some with sensors reacting to heat and others react to smoke. We have listed a guide below on the different types of alarm sensors available and which alarm is best suited to each application, helping you to avoid nuisance false alarms and to give you the best possible protection.

Here’s our guide to choosing the right alarm for installation in each area within a property. 


Multi-sensor alarms contain optical and heat sensors to detect both smoke and heat. They typically have the best response to all fire types from fast flaming to slow smouldering. Multi Sensor Alarms also intelligently monitors both sensors, the risk of nuisance alarms is virtually eliminated.

Multi-Sensor smoke alarm installations are most suitable for: Hallway, Landing, Living Room, Dining Room, Bedrooms.

Optical Sensors

Optical Smoke Alarms use an infra-red beam to detect smoke. They detect smoke from slow, smouldering fires such as electrical fires.

Optical smoke alarm installations are most suitable for: Hallway, Landing, Living Room, Dining Room.

Heat Sensors

Ideal for kitchens as they won’t cause nuisance alarms from cooking fumes, heat alarms sensors only detect changes in temperature using a thermistor. Heat Alarms have a trigger level is set to 58°C degrees. Heat Alarms are not recommended to be used in any other areas of a domestic property as they will not provide the speed of response required, as above Smoke alarms should be used.

Fit Heat Alarms in: Kitchen, Garage.

Ionisation Sensors

Smoke alarms containing ionisation sensors use a small radioactive source to detect the invisible smoke particles given off by fast-flaming, clean burning fires such as bedding and clothing. Ionisation alarms shouldn’t be used in or near kitchens as they can be prone to false alarms from cooking fumes.

Fit Ionisation Sensors in: Bedrooms.

Regardless of the sensor type, alarms should be interconnected throughout a property to ensure all alarms sound in the event of an activation, providing audibility for the occupants. 

Linked or interconnecting alarms

With today’s ability to link devices via the Internet of Things, many domestic smoke and heat alarm installations are interlinked, meaning if one alarm is activated then all the alarms installed on the same circuit are also sounded.

There are many reasons for using wireless interconnection:

  • Eliminates tricky wiring runs
  • Saves time at installation
  • Reduces mess and disruption during installation
  • Saves money
  • Makes it easier to add in new alarms and accessories

Which smoke alarms should I choose and where should they be fitted?

There is a general rule for smoke alarm positioning please see below:

Bedrooms – Optical smoke detectors OR combined optical smoke and heat detector.

Landings – Ionisation smoke alarms OR Combined optical smoke and heat detector.

Kitchen and Garage – Heat alarms

Get in touch to find out more about Red Electrical’s electrical maintenance services or call us on 0800 RED ELEC.

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