Smoke and CO Alarm Regulations for Landlords: 2026 Requirements

The legal framework for smoke and carbon monoxide alarms in rental properties is set out in the Smoke and Carbon Monoxide Alarm (England) Regulations 2015, as significantly amended by the Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022. These regulations apply to all private rented sector properties in England.

The original 2015 regulations required smoke alarms on every storey and CO alarms only in rooms with solid fuel appliances (wood burners, coal fires). The 2022 amendment expanded the CO alarm requirement to cover all rooms with any fixed combustion appliance, most significantly including gas boilers and gas fires.

The key legal obligations for landlords are:

• Smoke alarms: At least one smoke alarm must be installed on every storey of the property that contains a room used wholly or partly as living accommodation.
• Carbon monoxide alarms: A CO alarm must be installed in every room that contains a fixed combustion appliance (excluding gas cookers).
• Testing: All alarms must be checked to ensure they are in proper working order on the day a new tenancy begins (or as close to that day as reasonably practicable).
• Repair and replacement: While not explicitly stated in the regulations, the general duty of care and the Housing Act 2004 mean landlords should repair or replace faulty alarms promptly when notified by tenants.

It is worth noting that Scotland has its own regulations under the Housing (Scotland) Act 1987 as amended by the Fire and Smoke Protection (Scotland) Regulations 2022, which require interlinked alarms in all Scottish homes (including private rentals). Wales follows the English regulations with some local variations.

The Renters' Rights Act is expected to further strengthen these requirements, potentially mandating mains-wired alarms in all new tenancies and requiring landlords to proactively check alarm functionality during periodic inspections rather than only at tenancy commencement.

Getting the placement right is just as important as installing the alarms. Incorrectly positioned alarms may not detect smoke or CO quickly enough to protect your tenants.

Smoke alarms — location requirements:

At least one smoke alarm on every storey that contains living accommodation. In practice, the optimal locations are:

• Hallways and landings: The ideal primary location on each storey, as these are the main escape routes and smoke naturally rises and spreads through these areas.
• Living rooms and bedrooms: Additional alarms here provide earlier warning, particularly for sleeping occupants. While the regulations only require one per storey, installing detectors in bedrooms is strongly recommended.
• Kitchens: Use a heat detector rather than a smoke detector to avoid false alarms from cooking. The regulations refer to smoke alarms, but a heat alarm in the kitchen satisfies the spirit of the requirement while being practical.

Mounting position: Smoke alarms should be mounted on the ceiling, at least 300mm from any wall or light fitting. If ceiling mounting is not possible, they can be mounted on a wall between 150mm and 300mm below the ceiling. Avoid locations near air vents, extractor fans, or areas of high airflow that could prevent smoke from reaching the detector.

Carbon monoxide alarms — location requirements:

A CO alarm must be installed in every room containing a fixed combustion appliance, including:

• Rooms with gas boilers (including combi boilers in kitchen cupboards — the alarm should be in the room, not inside the cupboard)
• Rooms with gas fires
• Rooms with oil-fired boilers
• Rooms with wood-burning stoves or open fires

CO alarms should be mounted at head height — between 1m and 3m from the potential source of CO. Unlike smoke, carbon monoxide is roughly the same density as air and does not necessarily rise, so ceiling mounting is not required (though it is acceptable). Position the alarm where it can be heard from sleeping areas.

Note on gas cookers: The 2022 regulations specifically exempt rooms containing only a gas cooker from the CO alarm requirement. However, the Gas Safe Register and most safety organisations recommend fitting a CO alarm in the kitchen regardless.

The regulations do not specify which type of alarm you must install, but the choice affects reliability, tenant safety, and your ongoing maintenance burden.

Battery-only alarms:

The cheapest option, typically £10–£25 each. These satisfy the minimum legal requirement but have significant drawbacks:

• Tenants can remove batteries, leaving the alarm non-functional.
• Battery replacement creates an ongoing maintenance obligation.
• Cheaper models may have shorter lifespans (5 years vs 10 years for quality units).

If using battery alarms, choose models with sealed 10-year lithium batteries that cannot be removed. These cost around £15–£30 each and eliminate the battery replacement issue.

Mains-wired alarms with battery backup:

These are wired into the property's electrical circuit and have a backup battery that activates during power cuts. They cost more to install (£40–£80 per alarm plus installation) but offer significant advantages:

• Cannot be easily disabled by tenants.
• Always powered (with battery backup for outages).
• Can be interlinked so all alarms sound when one detects smoke or CO.
• Required in HMOs and strongly recommended for all rental properties.

Interlinked alarms:

Interlinked systems connect all alarms in the property so that when one activates, every alarm sounds. This ensures occupants on different floors are alerted immediately. Interlinking can be achieved through:

• Hardwired: Alarms connected by a dedicated cable. Most reliable but requires electrical installation work.
• Radio frequency (RF) interlink: Wireless interlinking between compatible alarms. Easier to retrofit but more expensive per unit (£30–£50 each).

Interlinked alarms are mandatory in Scotland for all homes and are required by HMO licence conditions across England. Even where not legally required, interlinking is the single most effective improvement you can make to fire detection in a rental property.

Smart alarms:

Connected alarms (such as those from Nest, Ring, or FireAngel) can send notifications to the landlord's phone when activated or when the battery is low. These are useful for portfolio landlords who want remote monitoring, but they cost more (£80–£130 each) and require Wi-Fi connectivity. They satisfy the legal requirements as long as they also provide a local audible alarm.

Sensor types:

• Optical (photoelectric) smoke alarms: Best for detecting slow-burning, smouldering fires. Recommended for hallways, landings, and bedrooms.
• Ionisation smoke alarms: Better for detecting fast-flaming fires. More prone to false alarms from cooking. Not recommended for kitchens.
• Heat alarms: Activated by temperature rise, not smoke. The correct choice for kitchens to avoid cooking-related false alarms.
• Multi-sensor alarms: Combine optical and heat detection. More expensive but offer the best all-round protection and reduced false alarms.

Installing alarms is only half the obligation. You must also ensure they are working and maintain them throughout the tenancy.

At the start of each new tenancy:

The regulations require you to check that every smoke and CO alarm is in proper working order on the day the tenancy begins. This means:

• Physically pressing the test button on each alarm and confirming it sounds.
• Checking that battery-powered alarms have adequate battery life.
• Verifying that mains-wired alarms are receiving power (the indicator light is on).
• For interlinked systems, testing that activating one alarm triggers all others.

Documentation: Record the test with a dated and signed checklist. Include the location of each alarm, the type, and the test result (pass or fail). Take a photograph of the checklist with the alarm visible if possible. This documentation is your evidence of compliance if the local authority investigates.

During the tenancy:

The regulations only explicitly require testing at the start of a new tenancy. However, good practice (and your general duty of care) means you should:

• Include a clause in the tenancy agreement reminding tenants to test alarms monthly.
• Respond promptly if tenants report a faulty alarm.
• Check alarms during routine property inspections (quarterly or six-monthly).
• Replace battery-only alarms before the end of their rated lifespan.

Alarm lifespan:

Most smoke alarms have a manufacturer's rated lifespan of 10 years. CO alarms typically last 5 to 7 years. After this period, the sensor degrades and the alarm may not detect smoke or CO reliably, even if the test button still works. Replace alarms before they reach the end of their rated life. The manufacture date is printed on the back of the unit.

What to do if a tenant removes or disables an alarm:

If you discover during an inspection that a tenant has removed batteries or disabled an alarm, replace or repair it immediately. Document the issue in writing to the tenant and include a reminder of their responsibility to maintain the alarms in working order. While the legal obligation to install and test sits with you, tenants have a responsibility not to tamper with safety equipment.

The enforcement regime for smoke and CO alarm regulations is separate from the EICR regime, with its own penalties and processes.

Remedial notice process:

If a local authority determines that a landlord has not complied with the regulations, they must first serve a remedial notice. This notice gives the landlord 28 days to install the required alarms. If the landlord complies within this period, no penalty is imposed.

If the landlord fails to comply with the remedial notice:

• The local authority can arrange for the alarms to be installed themselves, with reasonable access to the property.
• The local authority can impose a penalty charge of up to £5,000.
• The landlord must pay the costs of the local authority's intervention.

Repeat offences:

The £5,000 penalty can be imposed each time a landlord fails to comply with a remedial notice. For a portfolio landlord with multiple non-compliant properties, the cumulative penalties can be substantial. Local authorities can also take the pattern of non-compliance into account when setting the level of the fine.

Interaction with other penalties:

Smoke and CO alarm non-compliance often coincides with other electrical safety failures. A local authority investigation triggered by a missing smoke alarm may also reveal a missing EICR (up to £30,000 fine) or an unlicensed HMO (unlimited fine). The cumulative exposure from multiple breaches can be severe.

Insurance implications:

If a fire or CO incident occurs in a property without compliant alarms, your landlord insurance may refuse to pay out. Insurers expect landlords to comply with all statutory obligations, and non-compliance can be treated as a material non-disclosure that voids the policy. The cost of a few alarms is trivial compared to the potential uninsured loss from a fire.

Civil liability:

If a tenant is injured or killed in a fire or CO incident and you did not have compliant alarms, you face significant civil liability. The tenant (or their family) can sue for damages, and the absence of required alarms makes it very difficult to argue you met your duty of care. Courts have awarded substantial damages in cases where landlords failed to install basic safety equipment.

The cost of compliance:

For context, a full set of quality sealed-battery smoke and CO alarms for a typical 2-bedroom property costs around £60–£100. Mains-wired interlinked alarms cost more to install (£200–£400) but last longer and are more reliable. Either way, the cost is negligible compared to the penalties, insurance risks, and moral responsibility of protecting your tenants' lives.