Addressable or Conventional Fire Alarm System?

If you’re planning a new fire alarm system (or replacing an old one), one question comes up every time: should you choose a conventional system or an addressable system?

Both can be compliant and both can protect people effectively — but they work very differently, and the right choice depends on building layout, risk, future changes, and how quickly you need to identify the source of an alarm or fault.

If you’d like us to recommend the right option for your site, see our Fire Alarm Systems page, or jump straight to Fire Alarm Installation or Fire Alarm Maintenance.

Choose conventional if:

• The building is small and simple (small shop, small office, single-block premises)

• You’re happy with alarms showing a zone rather than an exact device location

• You want a lower equipment cost

• The building is unlikely to change much over time

Choose addressable if:

• The building is larger, has multiple floors/areas, or a complex layout

• You want the panel to show the exact detector/call point in alarm or fault

• You need cause & effect (AOV, door release, plant shutdown, etc.)

• You want a system that’s usually easier to expand and adapt

Not sure? A quick survey and design review will confirm what’s appropriate for your building and use case — and it should be aligned with BS 5839 guidance.

A conventional fire alarm system is the simpler of the two. Devices are wired on radial circuits, typically split into:

• Detection zones (detectors and manual call points grouped together)

• Sounder circuits (sounders and visual alarm devices)

When a device triggers, the panel identifies the zone in alarm (for example “Zone 2 – First Floor Offices”), rather than the exact device.

• Smaller premises where “zone location” is enough

• Straightforward layouts with short cable routes

• Projects where the specification is simple and cost sensitive

• Often lower equipment cost

• Simple to use and straightforward for occupants

• A good option for small buildings where detailed location isn’t essential

• An alarm or fault usually shows only the zone, not the exact device

• Fault finding can take longer on larger sites (more engineer time)

• More circuits can mean more cabling in some layouts

• Less flexibility for complex cause & effect requirements

An addressable fire alarm system uses a loop (or multiple loops) where each device has a unique address. That means the panel can identify:

• Exactly which device is in alarm (not just the zone)

• Exactly which device has a fault or needs attention

• The system status more precisely during testing and maintenance

When the system is commissioned, each device address is linked to a location (for example “Smoke detector – 2nd floor corridor outside Flat 6”).

• Medium and larger buildings

• Multi-area sites where fast location info matters

• Buildings with integrations (AOVs, door release, plant shutdown)

• Sites likely to expand or change use over time

• Exact device location for alarms and faults

• Faster investigation and less disruption during alarms

• More flexibility for zoning and cause & effect

• Often less cabling than conventional in many layouts

• Usually easier to add devices later (when designed properly)

• Higher initial equipment cost in many cases

• Requires competent commissioning/programming

• If poorly designed or maintained, nuisance alarms can still happen (same as any system)

This is where people get surprised.

Equipment cost: Conventional devices are often cheaper per unit.
Installation cost: Addressable can be cheaper to install in many buildings because loop wiring can reduce cabling — but it depends on the layout.
Lifetime cost: Addressable can be cheaper over time because fault finding is faster, the panel gives clearer information, and modifications/extensions are often simpler.

The “cheapest” system isn’t always the best value. If a system saves money on day one but costs more in repeated callouts and downtime, it’s a false economy.

In real life, this is one of the biggest reasons sites move to addressable.

• With conventional, you might know “Zone 3” is in alarm — but Zone 3 could contain several detectors and call points.

• With addressable, the panel shows the exact device (for example “Heat detector – Kitchen – Rear”).

That difference can mean:

• Faster investigation

• Faster reset

• Less disruption to staff/residents

• Better control of repeat false alarms

If you need the fire alarm to control anything else, addressable is often the sensible choice.

Common examples:

• Automatic opening vents (AOV / smoke ventilation)

• Door release (magnetic locks / hold-open devices)

• Plant shutdown (extract systems, gas shut-off, etc.)

• Lift controls

• Paging/voice systems in larger premises

These functions typically require cause & effect programming and clear device identification — which addressable systems handle more naturally.

The correct system type should be suitable for the building and how it’s used — and the design should follow the relevant guidance in BS 5839 (including documentation, zoning, device selection, commissioning and ongoing maintenance).

If you want a simple overview of what BS 5839 is and why it matters,
https://cobrafireandsecurity.co.uk/what-is-bs-5839/

For HMOs and multi-occupancy buildings, the challenges are usually:

• Faster location of alarms (so you can respond quickly)

• Reducing unwanted alarms that disrupt residents

• Managing maintenance and callouts efficiently

In many conversions and multi-let blocks, addressable systems are often the practical option because they make investigation, maintenance, and future changes easier — especially where the building layout is complex.

1. How big is the building and how complex is the layout?

2. Do we need exact location info or is “zone” enough?

3. Are there any integrations required? (AOV/doors/plant etc.)

4. Will the building change in the next 1–5 years?

5. How important is fast fault finding and minimising disruption?

6. What does the fire risk assessment / fire strategy require?

If you’re unsure, a quick site survey and design review prevents expensive mistakes.

• Choosing conventional purely on price for a building that’s already too complex

• Poor zoning (zones that are too large or don’t match the building layout)

• “Copy and paste” device selection without considering nuisance alarm risk

• No proper commissioning, documentation, or user training

• No maintenance plan (this is where issues start)

If you’re deciding between addressable vs conventional, we can recommend the right option based on:

• building layout and use

• likely system category requirement

• integrations needed (AOV/doors/plant)

• future expansion plans

• budget vs lifetime value

For design, install and commissioning, see:
https://cobrafireandsecurity.co.uk/fire-alarm-installation/

For ongoing servicing and compliance support, see:
https://cobrafireandsecurity.co.uk/fire-alarm-maintenance/

Reviewed: 21/01/2026 Our articles are reviewed regularly. However, any changes made to standards or legislation following the review date will not have been considered. Please note that we provide abridged, easy-to-understand guidance. To make detailed decisions about your fire safety provisions, you might require further advice or need to consult the full standards and legislation.