A properly designed fire alarm system gives the people in a building the earliest possible warning of fire. For most homes that means mains-wired, interlinked smoke and heat alarms, so when one sounds they all sound. For HMOs and larger buildings it may mean a panel-based system and emergency lighting. Polarity Electrics provides fire alarm installation in London for homeowners, landlords, HMOs and businesses, designed to the relevant British Standards and certified on completion.
Smoke alarm installation for landlords
Under the Smoke and Carbon Monoxide Alarm (Amendment) Regulations 2022, which apply in England from 1 October 2022, landlords must:
- Fit at least one smoke alarm on every storey of the property that has a room used wholly or partly as living accommodation
- Fit a carbon monoxide alarm in any room used as living accommodation with a fixed combustion appliance, such as a gas boiler or wood burner (gas cookers are excluded)
- Repair or replace alarms once told they are faulty
The regulations set the minimum. Many landlords choose mains-wired, interlinked alarms because they do not rely on tenants replacing batteries, every alarm sounds together, and they are more robust against tampering. HMO licences and local authority guidance often expect a higher standard than the minimum. Our guide to landlord smoke alarm regulations explains the rules in more detail.
Mains-wired, interlinked alarms
BS 5839-6 is the code of practice for fire detection and alarm systems in domestic premises. It describes systems by grade (how the system is powered and controlled) and category (how much of the home is covered). For a typical house or flat we commonly install:
- Mains-powered smoke alarms with a built-in standby battery, so they keep working during a power cut
- Heat alarms in kitchens, where smoke alarms would cause nuisance alarms from cooking
- Interlinking, either hard-wired or radio-linked, so all alarms sound together
- Carbon monoxide alarms near fixed combustion appliances
Mains-wired alarms are installed on a suitable circuit and tested, and the work is certified. A rewire or renovation is an ideal time to fit them; see our rewiring service.
HMO fire alarm systems to BS 5839-6
Houses in multiple occupation need a fire alarm system appropriate to their size, layout and the way they are occupied. The right grade and category are normally set by the fire risk assessment and your local authority's licensing requirements. Depending on the property, this could be an interlinked mains-powered system with detectors in escape routes and higher-risk rooms, or a panel-based Grade A system with call points, sounders and a control panel for larger HMOs.
We design and install HMO systems in line with BS 5839-6 and your council's requirements, and provide the certification you need for your licence application or renewal. HMOs also need a current EICR; see our guide to HMO EICRs in London.
Emergency lighting
Emergency lighting switches on automatically if the normal lighting fails, so people can find their way out safely. It is commonly required on escape routes in HMOs, blocks of flats and commercial premises, depending on the fire risk assessment. We install maintained and non-maintained emergency luminaires and exit signs designed in line with BS 5266-1, and can carry out the periodic testing that keeps the system compliant.
What's included
- A survey of the property and review of any fire risk assessment or licence requirements
- A system design specifying alarm types, locations, grade and category
- Supply and installation of mains-wired, interlinked smoke, heat and CO alarms, or panel-based systems
- Emergency lighting and exit signage where required
- Full testing and commissioning, and a demonstration of how to test and silence the system
- Certification for your records, tenants and local authority
Fire alarm installation pricing
We give a fixed written quote after a survey. As a guide, the figures below are typical London market ranges rather than published prices:
| System | Typical London market range |
|---|---|
| Mains-wired, interlinked alarms in a flat | £250 – £500 |
| Mains-wired, interlinked alarms in a 3–4 bed house | £400 – £900 |
| Panel-based HMO system | £1,500 – £4,000+ |
Cost depends on the number of detectors, whether alarms are hard-wired or radio-linked, access for cabling, and whether emergency lighting is required.
How the process works
- Survey – we visit the property and review your requirements.
- Fixed written quote – with a clear system specification.
- Installation – most domestic systems are fitted in a day, with minimal disruption.
- Testing and commissioning – every device is tested and interlinking checked.
- Certification – you receive certificates for your records and licence.
Why choose Polarity Electrics
- NICEIC Approved Contractor (Enrolment No. 602034000) and Part P registered
- 8+ NICEIC-certified engineers and more than 5,000 jobs completed
- Experience with landlord, HMO and commercial requirements
- Combine alarms with an EICR and PAT testing in one visit
- No call-out charge and 12-month workmanship guarantee
- £10M public liability insurance and a landlord portal with bulk booking
Areas covered
We install fire alarms across London and the Home Counties, including North London, East London, Hackney, Waltham Forest, Brent, Lambeth, Enfield and Essex. See all areas covered.
Related services
- EICR London – required for rented homes and HMOs
- PAT testing – for appliances supplied to tenants
- Commercial EICR – for businesses and mixed-use buildings
- Rewiring
Need smoke alarms or a fire alarm system? Call 0203 908 4790, email info@polarityelectrics.com or book online for a fixed written quote.
Frequently asked questions
What smoke alarms do landlords need to fit?
In England, landlords must fit at least one smoke alarm on every storey with living accommodation and a CO alarm in any room with a fixed combustion appliance, excluding gas cookers. Many landlords choose mains-wired, interlinked alarms as a more reliable option.
What does interlinked mean?
Interlinked alarms are connected, either by cable or radio, so that when one detects smoke or heat every alarm in the property sounds.
What fire alarm system does an HMO need?
It depends on the size, layout and occupancy of the property. The fire risk assessment and your local authority's licensing requirements set the grade and category under BS 5839-6, and we design the system to match.
Do I need emergency lighting?
Emergency lighting is commonly required on escape routes in HMOs, blocks of flats and commercial premises, depending on the fire risk assessment. We can advise and install systems designed to BS 5266-1.
How much does fire alarm installation cost in London?
Typical London market ranges are around £250 to £500 for mains-wired interlinked alarms in a flat, and more for houses and HMO panel systems. We give a fixed written quote after a survey.
Can you fit alarms at the same time as an EICR?
Yes. Landlords often combine smoke alarm installation with an EICR and PAT testing in a single visit.