Smoke and carbon monoxide alarm rules for landlords

In England, landlords must fit a smoke alarm on every storey with a room used as living accommodation, and a carbon monoxide alarm in any such room with a fixed combustion appliance other than a gas cooker. Alarms must be checked on the day each new tenancy begins and repaired once reported faulty (2015 Regulations, amended from 1 October 2022).

This guide sets out the rules as the regulations word them. Several popular pages are out of date on this subject. Some still describe CO alarms as only for solid fuel appliances, the position before October 2022. It is part of our landlord safety certificates checklist. We are EliteShires Property Services in Kenton, and we fit smoke and carbon monoxide alarms for landlords across Harrow, Kenton, Stanmore and Edgware.

What do the regulations actually require?

Regulation 4 of the 2015 Regulations sets three duties: a smoke alarm on every storey with living accommodation, a CO alarm in any lived-in room with a fixed combustion appliance other than a gas cooker, and a check on the day each new tenancy begins, with repairs once a fault is reported. The table sets them out in the regulations' own terms. The duties were last changed on 1 October 2022. A tidy-up on 1 May 2026 removed references to shorthold tenancies from the definitions, but the three duties were unchanged when we checked legislation.gov.uk in October 2026.

The three alarm duties for landlords in England (checked October 2026)

Three definitions in the regulations change how this works in a real house:

• A bathroom or lavatory counts as living accommodation (regulation 4(2)). A boiler in a bathroom needs a CO alarm in that bathroom. A storey with only a bathroom still needs a smoke alarm.
• A hall or landing counts as a room (regulation 4(4)). That is why the usual position for a smoke alarm is the hall and landing ceilings.
• A fixed combustion appliance burns fuel of any type to generate heat. GOV.UK's booklet gives that definition. Gas boilers, oil boilers, gas fires and wood burners all count. A purely decorative fireplace that does not work is not one, in the department's view.

Does a gas cooker or a boiler need a carbon monoxide alarm?

A gas cooker on its own does not. A boiler does, if it is in a room used as living accommodation. Gas cookers are expressly excluded from the CO duty. Every other fixed appliance that burns fuel for heat is in scope, whether it runs on gas, oil, coal or wood.

Which common set-ups need a CO alarm under the regulations

Do alarms have to be hard-wired?

No. The 2015 Regulations do not say what type of alarm to use, so battery alarms meet them. GOV.UK recommends smoke alarms to BS 5839-6 and carbon monoxide alarms to BS EN 50291. For battery alarms, it suggests sealed-for-life batteries. Heat detectors are not a substitute for smoke alarms.

Other rules can ask for more than the regulations do:

• HMO licence conditions often set their own fire detection standard. Read your licence before choosing alarms.
• Building work, such as a loft conversion or a rewire, has its own requirements. Your electrician or building control body will tell you what applies.
• Existing mains-wired alarms should be kept working and replaced like for like. Swapping a wired system for battery alarms is a downgrade, even where the regulations would allow it.

Mains-wired and interlinked alarms are electrical work, so book an electrician for those. For battery alarms, a handyman visit is enough.

Where should smoke and carbon monoxide alarms go?

The regulations don't set positions, so follow the manufacturer's instructions. GOV.UK's general guidance is that smoke alarms usually go on the ceiling of a hall or landing. Carbon monoxide alarms usually go at head height, on a wall or shelf, about one to three metres from the appliance.

Some practical points we follow when fitting:

1. Put the smoke alarm where the storey's escape route is, usually the hall and landing.
2. Keep smoke alarms out of kitchens and away from bathroom doors, where cooking fumes and steam cause false alarms. Repeated false alarms tend to end with a battery being taken out.
3. Fit the CO alarm in the same room as the appliance, not in the next room.
4. A mezzanine is not a separate storey in the department's view. A split-level house is not covered by the guidance, so treat each level with rooms as a storey.

What must you do on the day a tenancy starts?

Check that every alarm works on the day a new tenancy begins, and keep a record of the check. A new tenancy is one granted on or after 1 October 2022. A tenancy that simply follows on with the same landlord, same tenant and the same or substantially the same property doesn't count. Check-in day is still the sensible time to test.

GOV.UK's booklet says landlords should keep a record of when alarms are tested. It suggests the tenant signs the inventory to confirm the alarms were tested and working. The booklet also suggests showing tenants how to test their alarms and how often.

What if a tenant reports a faulty alarm?

You must check it and repair or replace it as soon as reasonably practicable. This duty was added on 1 October 2022 and applies whenever a tenant, or someone acting for them, reports a fault. It covers both smoke and carbon monoxide alarms.

A few situations come up often:

• A low-battery chirp. GOV.UK advises tenants to try a new battery first, then report the alarm if it still fails. A sealed-for-life alarm can't have its battery changed, so it needs replacing.
• An alarm past its replace-by date. Most alarms carry a manufacturer's replace-by date. An expired alarm should be replaced. Retesting it is not enough.
• A CO alarm sounding. Treat it as an emergency. A CO alarm sounding is not the same as an alarm being faulty, so don't assume it is a false alarm. The tenant should get out and call the gas emergency number. The appliance then needs a Gas Safe registered engineer before it is used again. We book gas safety checks with Gas Safe registered engineers.

Does the annual gas safety check cover your alarms?

No. The gas safety check covers the gas appliances, fittings and flues you provide. The alarm duty comes from different regulations. Many landlords assume the engineer's visit ticks both boxes. It doesn't, unless you ask for the alarms to be tested and recorded at the same visit. Combining them makes sense, and our engineers and handymen can do both on one booking.

Who is exempt from the alarm regulations?

Lodgers who share a kitchen or living room with the landlord, long leases, student halls, hotels, refuges, care and healthcare settings, low-cost home ownership and owner-occupiers are all outside the 2015 Regulations, according to GOV.UK's booklet. In detail:

• Lodgers who share a kitchen or living room with the landlord or the landlord's family.
• Long leases.
• Student halls, hotels and refuges, care homes, hospitals and hospices, and other healthcare accommodation.
• Low-cost home ownership homes, and owner-occupiers.

Social landlords have been covered since 1 October 2022. Houses and HMOs that need a licence are outside the regulations too, as the next section explains.

What changes if the property is licensed?

Houses and HMOs that need a licence are outside the 2015 Regulations altogether, whether or not the licence has been obtained. Instead, Schedule 4 of the Housing Act 2004 puts equivalent alarm requirements into every licence: a smoke alarm on each lived-in storey, a CO alarm in rooms with a fixed combustion appliance other than a gas cooker, both kept in proper working order, and a declaration to the council on demand. The licence conditions have no day-one check or report-and-repair wording, but testing at check-in is still the sensible way to keep alarms in working order.

In our area that covers Harrow's six selectively licensed wards, Brent's Kenton ward and Barnet's HMOs; our guide to licensing in Harrow, Brent and Barnet shows which applies to your address. A breach of a licence condition is a separate offence, now open to a civil penalty of up to £40,000. Our guide to landlord fines compares the penalties.

How does the council enforce the alarm rules?

Through a remedial notice, and then a penalty. If the council has reasonable grounds to believe you are in breach, it must serve a remedial notice within 21 days. You then have 28 days to take the action it specifies. If you don't, the council must arrange the work itself within 28 days, if the occupier consents. It can also charge a penalty of up to £5,000.

The £5,000 maximum is set by regulation 8. GOV.UK says it applies per breach. On legislation.gov.uk in October 2026, regulation 8 was unchanged by the Renters' Rights Act. That is lower than the £40,000 maximum for an EICR breach.

Where can you get alarms fitted or checked locally?

We fit, test and replace alarms on the same visit as other landlord work, and confirm the price, or the hourly rate and an estimate, before we attend. Book through our pages for handyman jobs in Harrow, alarm fitting in Kenton, handyman visits in Stanmore or small jobs in Edgware. If you are getting ready for a new tenancy, our guide to what to expect at a landlord safety inspection explains how a combined visit runs. Our list of documents to give tenants covers the paperwork at check-in. For every other check a let needs, go back to the full certificates checklist.