What you must do
What alarms are required and where
The Regulations specify three types of alarm. Which you need, and where, depends on your property's layout and appliances.
Smoke alarms must be installed in:
- The room most used for general daytime living (normally the living room).
- Every circulation space on each storey — this means every hall and landing.
Heat alarms must be installed in:
- Every kitchen. A heat alarm detects heat rather than smoke, using a thermistor that responds above 58°C.
Carbon monoxide (CO) alarms must be installed in:
- Any room or circulation space containing a fixed combustion appliance — such as a boiler, fire, heater, or stove burning solid fuel, oil or gas. Gas cookers and ovens are excluded.
- Any room that a flue passes through, even if there is no appliance in that room.
If your property has gas appliances, note that the gas safety regulations impose a separate annual inspection duty — it is a distinct obligation from the alarm requirement.
Open-plan layouts
Where the main living area is open-plan with the kitchen, a heat alarm may be used for that space, provided it is positioned no more than 7.5 metres from any point in the room.
Where an open fireplace would make a smoke alarm impractical (for example, due to nuisance from smoke), a heat alarm may be fitted in that room instead.
Standards and marking
All alarms must meet specific British Standards:
- Smoke and heat alarms must conform to BS 5839-6.
- Carbon monoxide alarms must conform to BS EN 50292.
Every alarm unit must be marked as British Standard compliant. Check the product packaging or the unit itself before purchasing.
Interlinking
Smoke and heat alarms must be interlinked — when one alarm activates, all alarms in the interlinked system sound together. This ensures an alarm in the kitchen is heard throughout the property.
Carbon monoxide alarms do not need to be interlinked.
Power supply and mounting
Smoke and heat alarms must be ceiling-mounted. They must be powered by one of the following:
- Mains-wired (connected to the fixed electrical installation — not a plug socket), or
- Sealed tamper-proof long-life battery units, or
- A combination of both types.
If mains-wired alarms are to be installed, they must be fitted by a qualified electrician, and it is recommended that the electrician is registered with a recognised electrical trade body.
Properties with existing Building Control alarm systems
Some properties — particularly newer builds or properties that have had extensions — will already have mains-wired alarms installed to meet Building Control requirements at the time of construction. If this applies to your property:
- Do not disable any existing mains-wired alarms.
- When they need replacing, replace them like-for-like with mains-wired units.
- Any additional alarms required to meet these Regulations (alarms in locations not covered by the Building Control installation) may be either mains-wired or sealed-battery units.
Keeping alarms working
Alarms must be in proper working order at the start of every new tenancy. After that:
- If a tenant reports a faulty alarm, the landlord must repair or replace it once informed.
- Testing alarms during the tenancy is the tenant's responsibility. It is good practice for landlords to demonstrate how to test the alarms at the start of a tenancy and to note this in the inventory or check-in documentation.
Penalties and enforcement
Failure to comply is an offence under Article 11B(4) of the Private Tenancies (Northern Ireland) Order 2006. The maximum fine on conviction is £2,500. Enforcement is carried out by Northern Ireland's 11 district councils.