Smoke and Carbon Monoxide Alarm Regulations 2022
Smoke and carbon monoxide alarms are governed by the 2015 Regulations as substantially amended in 2022. The 2022 amendments extended carbon monoxide alarm requirements to every room with a fixed combustion appliance (excluding gas cookers) — meaning that boilers, gas fires, wood burners, and multi-fuel stoves all now require alarms in the rooms where they are located. Civil penalties up to £5,000 per property apply (rising to £30,000). This page covers what the regime requires under the post-2022 framework, the alarm types that satisfy the standards, the start-of-tenancy testing obligation, and the operational practice that produces consistent compliance.
Why the regime matters more than its modest penalties suggest
Smoke and carbon monoxide alarm regulation is the single most cost-effective compliance regime in the private rented sector. The cost of compliance is typically £50-£200 per property — for alarms, batteries, and a few minutes of installation work. The cost of non-compliance is up to £5,000 per breach (rising to £30,000 in line with other regimes), plus the substantially higher human cost where a fire or carbon monoxide incident produces an injury or death that working alarms would have prevented.
Yet alarm regulation is also the regime where landlord compliance is most uneven. Many landlords assume any alarm satisfies the requirements; some leave the work to tenants; others install alarms once at the start of a tenancy and never check whether they continue to work. The 2022 amendments to the regime tightened the requirements substantially, and many landlords have not yet caught up.
This page sets out exactly what the regime requires, where the 2022 changes affect existing tenancies, and the operational practice that produces consistent compliance.
The legal framework
Smoke and carbon monoxide alarms in privately rented accommodation are governed by the Smoke and Carbon Monoxide Alarm (England) Regulations 2015, as amended by the Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022. The amended regime took effect on 1 October 2022.
The 2015 Regulations were originally applied to private rented sector lettings only. The 2022 amendments extended several requirements to social housing as well — but for private landlords, the 2022 changes mostly tightened the existing regime rather than introducing fundamentally new obligations.
What landlords must do
Smoke alarms
A working smoke alarm must be installed on every storey of the property where there is at least one room used wholly or partly as living accommodation. The “every storey” rule means:
- Single-storey flats: one smoke alarm.
- Two-storey houses: at least two smoke alarms (one upstairs, one downstairs).
- Three-storey houses: at least three smoke alarms.
- Properties with habitable basements or attics: an additional alarm in those spaces.
The location of the alarm on each storey must be appropriate — typically in the hallway or landing where it will detect smoke from any room. A smoke alarm in a bedroom or kitchen alone does not satisfy the requirement.
Carbon monoxide alarms
Under the 2015 Regulations as originally drafted, a carbon monoxide alarm was required only in any room with a solid fuel burning appliance (e.g. a wood burner or open fire). The 2022 amendments substantially expanded this to require a carbon monoxide alarm in every room used wholly or partly as living accommodation that contains a fixed combustion appliance (excluding gas cookers).
In practice this means:
- Any room with a gas boiler — typically the kitchen or a utility room.
- Any room with a gas fire — typically the living room.
- Any room with a solid fuel appliance (wood burner, multi-fuel stove, open fire).
- Any room with an oil-fired appliance (less common in residential).
Gas cookers are excluded from the carbon monoxide alarm requirement. The reasoning is that gas cookers are intermittent appliances under direct user control with adequate ventilation. Boilers and fires, by contrast, run unattended and are the most common sources of CO incidents.
Alarm types and standards
Smoke alarms must comply with BS EN 14604 — the European standard for smoke alarms. Carbon monoxide alarms must comply with BS EN 50291. Most alarms sold in the UK retail market satisfy these standards; check the packaging or the product code online before purchasing.
The regulations do not specify whether the alarms must be battery-powered or mains-wired. Both are acceptable. In practice:
- Battery alarms (sealed 10-year batteries) are the easier choice for most rented properties. £15-£25 per alarm. Battery lasts the alarm’s lifetime; replace the entire alarm at the end. No electrical installation required.
- Mains-wired alarms with battery back-up are required by HMO licence conditions in many cases and are the safer standard for larger properties. £40-£80 per alarm plus installation. Last 10+ years and operate during power cuts.
- Interlinked alarms — where activation of one sounds all of them — are not required by the 2015/2022 Regulations but are required by HMO licence conditions in many cases and are the gold standard for larger properties.
For non-HMO single-household lets, sealed-battery 10-year smoke and CO alarms are the simplest compliance route. Buy them once, install them at the start of the tenancy, and leave them in place for the alarm’s lifetime.
Testing at the start of every new tenancy
A specific obligation under the regulations: alarms must be tested at the start of every new tenancy. The “test” means physically pressing the test button and confirming the alarm sounds.
Best practice:
- Test all alarms in the presence of the tenant when they take occupation.
- Document the test — a brief written note (“Smoke alarms tested in tenant’s presence on [date]; all functioning”) signed by tenant and landlord.
- Photograph each alarm in situ at the start of the tenancy as part of the inventory.
- Provide written guidance to the tenant on how to test alarms during the tenancy and what to do if one stops working.
Once the start-of-tenancy test has been documented, the on-going responsibility for testing and battery replacement (where applicable) falls on the tenant. The landlord’s obligation is to ensure the alarms are operational at the start; the tenant’s obligation is to maintain that operation during their occupation.
Repair after notification
Where a tenant notifies the landlord that an alarm has failed (a sealed-battery alarm reaching end of life, a mains-wired alarm with a fault), the landlord must repair or replace the alarm. The 2022 amendments specify that this must be done as soon as reasonably practicable. There is no statutory timeframe but in practice within 7-14 days is the standard.
Penalties for breach
Local authorities enforce the Regulations through civil penalties:
- Penalty for breach: currently up to £5,000 per property per breach. Being raised to £30,000 in line with other compliance regimes (date subject to consultation).
- Remedial notices: the local authority can serve a notice requiring the landlord to install or repair alarms within a specified period. Failure to comply with the notice is a separate breach.
- Local authority remedial action: where the landlord does not act on a remedial notice, the local authority can carry out the works themselves and recover the cost from the landlord.
The penalty is per property, not per missing alarm. A landlord with five missing alarms across a single property faces one penalty (up to £5,000); a landlord with five missing alarms across five properties faces five penalties.
Insurance consequences: standard buy-to-let policies often require working smoke and CO alarms as a condition of cover. A fire-related claim where the alarms were missing or non-functional may be refused.
Common mistakes
Treating “smoke alarm in the hallway” as enough. The “every storey” rule means properties with multiple storeys need multiple alarms, regardless of layout.
Assuming gas cooker = no CO alarm. The exclusion for gas cookers is narrow. A kitchen with a gas boiler still needs a CO alarm even if the cooker is also gas.
Forgetting CO alarms in living rooms. Many landlords install a CO alarm near the boiler but forget that a gas fire in the living room also requires one in that room.
Not testing at tenancy start. The start-of-tenancy test is a specific statutory obligation. Failure to document the test means the landlord cannot prove compliance with this element of the regime.
Relying on a tenant’s assurance. “I’ll buy a smoke alarm and put it up” from a tenant is not compliance. The landlord must install (or have installed) the alarms before the tenancy starts.
Cheap battery alarms. 9V battery alarms with replaceable batteries fail more often than sealed-battery alarms. The cost saving (£5-£10 per alarm) is not worth the increased risk of mid-tenancy failure.
Operational best practice
A landlord operating professionally on alarms:
1. Audits the alarm position at every property. Walk through each property and confirm: smoke alarm on every storey, CO alarm in every room with a fixed combustion appliance.
2. Uses sealed 10-year battery alarms as standard. Buy a brand-name product (Aico, FireAngel, Kidde) rather than the cheapest available. Total cost for a typical 3-bedroom house: £80-£150.
3. Documents the start-of-tenancy test. A short paragraph in the inventory or a separate signed record. The documentation is the protection.
4. Replaces alarms preemptively at 8-9 years. Rather than waiting for end-of-life beep at year 10, replace during a void or routine inspection. This avoids tenant inconvenience and ensures continuous compliance.
5. Tests alarms during periodic inspections. A 30-second alarm test during the routine 6-month inspection confirms the alarm continues to function and identifies any failures the tenant has not reported.
6. Maintains a portfolio-wide alarm register. Property, alarm locations, install date, expected end-of-life. Easily checkable; replace cycle predictable.