London HMO Smoke Alarm Requirements: What Changed in 2022 and What Landlords Must Do Now

What Changed on 1 October 2022

The Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022 came into force on 1 October 2022, significantly extending the smoke alarm requirements for privately rented properties in England. The most important change for HMO landlords is the requirement to install a smoke alarm in every room used as sleeping accommodation — not just on each storey of the property as was required previously.

Before October 2022, the Smoke and Carbon Monoxide Alarm (England) Regulations 2015 required at least one smoke alarm on every storey where there was a room used as living accommodation. For an HMO, this meant one alarm per floor. The 2022 amendment went further: now each individual bedroom must have its own smoke alarm. For an eight-bedroom HMO spread over three floors, this could mean eight bedroom alarms plus corridor alarms, rather than the three storey alarms previously required.

Interlinked Alarms

Smoke alarms in HMOs must be interlinked so that when one alarm activates, all alarms throughout the property sound simultaneously. This is not a new requirement introduced in 2022 — it has been a standard condition of HMO licensing since the 2006 HMO Management Regulations — but it is now reinforced by the amended national regulations. An HMO with battery-powered stand-alone alarms that are not interlinked is non-compliant, regardless of how many alarms are installed.

Interlinked alarms can be achieved by hard-wired mains systems (the preferred approach for all but the simplest HMOs) or by radio-frequency (RF) wireless interlinked systems where hard-wiring is impractical. Hard-wired systems should have battery backup to operate during a mains power failure. BS 5839-6 is the relevant British Standard for the design, installation, commissioning, and maintenance of fire detection and fire alarm systems in domestic premises — Grade D1 (mains-powered with battery backup) is the typical specification for HMOs.

Heat Detectors in Kitchens

Smoke alarms are not appropriate for use in kitchens because normal cooking activity produces smoke and steam that trigger false alarms. The 2022 Regulations do not require a smoke alarm in the kitchen; instead, they require a heat detector in any kitchen in a rental property. The heat detector must also be interlinked to the rest of the alarm system. A rate-of-rise heat detector (which triggers when temperature rises rapidly) or a fixed temperature heat detector (which triggers when temperature reaches a threshold, typically 58 degrees Celsius) are both suitable.

Carbon Monoxide Alarms

The 2022 amendment extended the carbon monoxide alarm requirement to all rooms containing any fixed combustion appliance — not just solid fuel appliances as was the case under the 2015 Regulations. This means a carbon monoxide alarm is now required in any room containing a gas boiler, gas fire, or oil-fired appliance. For most HMOs, this means a carbon monoxide alarm in the boiler room or the room where the boiler is located. If the boiler is in the kitchen, the CO alarm requirement overlaps with the heat detector requirement — both are needed.

What Landlords Must Do

Every HMO landlord in London should audit their current alarm provision against the 2022 requirements. The audit should confirm: that there is a smoke alarm in every bedroom; that all alarms are interlinked; that there is a heat detector in the kitchen, also interlinked; that there is a carbon monoxide alarm in every room with a fixed combustion appliance; and that all alarms are in working order at the start of each tenancy.

Landlords must test alarms at the start of each new tenancy. Ongoing testing is the responsibility of the tenant. However, landlords should confirm that alarms are operational during any routine inspection visit. Alarms that are more than ten years old should be replaced regardless of apparent function — the internal sensors in smoke alarms degrade over time. The manufacture date is usually printed inside the alarm unit.

Enforcement

Local authorities enforce the smoke and CO alarm regulations through the Housing Act 2004 framework. A landlord who fails to comply after receiving a remedial notice from the local authority can be issued with a civil penalty of up to £5,000. For HMO landlords, non-compliance with alarm requirements also puts the HMO licence at risk — local authorities can refuse to renew or can revoke an HMO licence where a landlord has persistently failed to maintain fire safety standards. London's local authorities are among the most active in the country for HMO licensing enforcement.