Fire Alarm System Installation, Design & Commissioning
BS 5839-compliant fire detection and alarm systems for commercial, industrial and residential buildings across the UK. Designed, installed, commissioned, maintained and fault-found by our own engineers. All in-house, BAFE-registered, FIA-member.
We deliver every category of fire alarm system under BS 5839, from a single-panel manual setup in a small office through to multi-panel networked estates with thousands of devices, voice alarm integration and full life-safety monitoring. Whatever the building, whatever the risk profile, the same WSD engineers handle the design, the install, the commissioning and the ongoing maintenance.
The fire alarm systems we design and install
Every fire alarm WSD installs is designed against the building’s actual fire strategy, not a generic template. We work to BS 5839-1 for non-domestic buildings, BS 5839-6 for dwellings, and BS 5839-8 where voice alarm or public address voice alarm is required.
We design and install:
- Addressable fire alarm systems for medium and large buildings where individual device identification matters
- Conventional fire alarm systems for smaller buildings where zone-level identification is sufficient
- Hybrid systems combining addressable and conventional zones for cost-balanced retrofits
- Networked multi-panel systems for large estates, multi-tenant buildings and campus environments
- Voice alarm (VA) systems to BS 5839-8 for phased evacuation and emergency messaging
- PA-VA systems combining everyday public address with fire alarm voice messaging
- Wireless fire alarm systems for heritage buildings and sites where cabling is impractical
If you’re not sure which category your building needs, the section below explains how the BS 5839 categories work. Or just talk to us and we’ll walk you through it against your fire risk assessment.
BS 5839 categories explained
BS 5839-1 splits fire alarm systems into three broad types: manual (M), life protection (L) and property protection (P). The category tells you what the system is designed to protect, not the technology behind it.
Category M – Manual systems. Call points only, no automatic detection. Required as the minimum standard in many commercial buildings, but rarely sufficient on its own.
Category L1 – Maximum life protection. Automatic detection throughout the entire building including roof voids, storage cupboards and plant rooms. Provides the earliest possible warning to anyone in the building.
Category L2 – Life protection in escape routes, rooms opening onto escape routes, and high-risk rooms. A step up from L3 where specific risks (kitchens, plant rooms, sleeping accommodation) warrant additional detection.
Category L3 – Life protection in escape routes and rooms opening onto escape routes. Gives occupants more time to leave the building than L4 by detecting fire before it reaches the escape route itself.
Category L4 – Life protection in escape routes only. The minimum level of automatic detection that still gives escape route warning. Common in lower-risk commercial buildings.
Category L5 – Custom life protection. A bespoke specification driven by a specific fire risk assessment. Used where standard categories don’t fit the building’s risk profile.
Category P1 – Maximum property protection. Automatic detection throughout the entire building, designed for the earliest possible warning to allow property protection response.
Category P2 – Property protection in defined high-risk areas only. Often used where insurance requires automatic detection in specific zones such as server rooms or archives.
The category your building needs is determined by your fire risk assessment and any specific requirements from your insurer, the local fire authority, or the building’s funder. If you’ve inherited a system and aren’t sure which category it was designed to, we can verify it as part of a takeover survey.
Commissioning, testing and certification
Every system we install is fully commissioned to BS 5839 before handover. That includes loop diagnostics, cable resistance testing, functional testing of every device, cause-and-effect testing across the full programmed matrix, integration testing with linked systems (suppression release, smoke control, BMS, lift homing), the BS 5839 commissioning certificate issued on completion, as-fitted drawings and the asset register handed over, on-site training for the people who’ll use the system day-to-day, and a maintenance and zone plan posted at the panel.
The same engineers who designed the system commission it. We don’t sub-contract commissioning out to a third party.
Recent installs & upgrades.
A small selection of jobs we have delivered or maintain in this area.
Aldgate
Self-test emergency lighting retrofit across six floors, including monthly compliance reporting.
Central House
Networked addressable fire alarm system across 400+ devices, with graphics-panel monitoring and an ongoing maintenance contract.
Got questions? We've answered the common ones.
Quick answers on cover, callout times, accreditations and what working with us actually looks like. Still got a question? Get in touch.
What size of project do you take on?
Anything from a single-panel fire alarm install in a small commercial unit through to a multi-floor refit across a live multi-tenant building. Most of our work runs from focused fire alarm and emergency lighting packages up to six-figure suppression and pump room schemes for main contractors and M&E consultants.
Are you accredited?
Yes. WSD holds BAFE (SP203-1), NICEIC Approved Contractor and SafeContractor accreditations, and we are members of the FIA and BSI. Insurance: £5m public liability, £10m employers’ liability, £1m professional indemnity, £5m product liability. Certificates available on request.
How do I get a quote?
Email [email protected] or call 01527 387 918 during office hours. We’ll talk through what you need, arrange a site visit if useful, and quote against the actual scope. No menu of upsells, no commitment until you’ve seen the proposal.
What’s a Cat L2 fire alarm system?
A middle ground between L1 (detection everywhere) and L3 (escape routes only) under BS 5839-1. Automatic detection in escape routes plus rooms that present a high fire risk — kitchens, plant rooms, electrical intake rooms and similar. The most commonly specified category for hotels, residential blocks and offices where the fire strategy needs more than escape-route coverage but doesn’t require L1.
Can you install voice alarm systems?
Yes, both VA and PA-VA, designed and commissioned to BS 5839-8. Common in high-rise residential, shopping centres, transport hubs and large commercial buildings.
Do you handle Fire Risk Assessments?
We don’t carry out FRAs ourselves but we coordinate them through accredited fire safety professionals we work with regularly. If you need an FRA alongside an alarm project, we’ll arrange it and feed the findings into the design.
What’s a Cat P1 fire alarm system?
The highest level of property protection. Automatic detection throughout the entire building, designed for the earliest possible warning to allow a property protection response (typically a call to a remote monitoring centre or fire brigade). Often required by insurers for high-value buildings or critical infrastructure.
What’s a Cat L1 fire alarm system?
The highest level of life protection under BS 5839-1. Automatic detection throughout the entire building, including voids, cupboards and plant rooms. Provides the earliest possible warning to anyone in the building. Typically required in hotels, care homes, and any building where occupants may be asleep or otherwise vulnerable.
Do you cover the whole UK?
Yes, we deliver maintenance contracts and projects nationally from our Bromsgrove HQ. Most of mainland Britain is within a routine response window for reactive maintenance work.
Sites further from the Midlands may have slightly longer response windows for reactive call-outs; we can provide a map of typical response times by area during the initial survey if it’s relevant to your site.
What’s the difference between addressable and conventional fire alarms?
A conventional system divides the building into zones and tells you which zone an alarm has come from. An addressable system identifies the exact device within the zone. Addressable is the standard for medium and large buildings now because it makes fault-finding and maintenance much faster, and because the cost difference at the device level has narrowed significantly over the last decade.
How often do fire alarms need to be tested?
BS 5839 recommends a weekly user test (a single call point activated to check the alarm sounds), six-monthly servicing visits at a minimum, and an annual full functional test of every device. Most of our maintenance contracts are structured around four quarterly visits to spread the workload.
Detail that often comes up.
Standards, integration, manufacturers and the questions we get asked most. Skim or dive in.
- Manufacturers
- Voice alarm
- Building types
- Fault finding
- FRAs
- Maintenance
- Standards
Manufacturers
We install systems from the established fire detection manufacturers used across the UK commercial sector. Manufacturer selection is driven by the project brief, the M&E consultant’s specification if there is one, the building’s existing infrastructure for retrofits, and the client’s long-term maintenance preferences. We don’t push one manufacturer over another. If the spec calls for it, we install it.
Advanced
Large addressable systems, networked installations
Kentec
Addressable and conventional panels across all building sizes
Hochiki
Addressable detection devices and panels, ESP loop systems
Apollo
Addressable detection devices, XP95 and Discovery ranges
Talk to our team
We will walk through your project, scope the work, and quote against what you need.
Voice alarm
Voice alarm (VA) and public address voice alarm (PA-VA) systems are required where simple sounder evacuation isn’t enough, typically because:
- The building is too large or complex for a single-stage evacuation
- Phased evacuation is part of the fire strategy
- The occupant numbers, demographics or location need a clearer instruction than a sounder can give
We design, install, commission and maintain VA and PA-VA systems to BS 5839-8. Typical installations include:
- High-rise residential developments
- Commercial office buildings with phased evacuation strategies
- Shopping centres and retail destinations
- Transport hubs
- Educational facilities and student accommodation
- Hotels, leisure venues and public buildings
- Large industrial and distribution facilities
Where the building has both PA and VA needs (i.e. everyday announcements and emergency messaging), we install a combined PA-VA system rather than two separate ones. The fire alarm side takes priority over normal PA operation when activated, and the system can be integrated with suppression, smoke control and other life safety systems to give a coordinated emergency response.
Talk to our team
We will walk through your project, scope the work, and quote against what you need.
Building types
WSD installs fire alarm systems across every commercial and industrial building type. Notable sectors include:
Offices and commercial premises
Single tenant through to large multi-tenant fit-outs
Retail units and shopping centres
High footfall environments with phased evacuation requirements
Residential developments
Apartment blocks, build-to-rent, student accommodation
Hotels and leisure facilities
Guest safety and BS 5839-1 Cat L1 / L2 environments
Industrial and manufacturing facilities
Including process areas with bespoke detection
Warehousing and logistics centres
Large open spaces often requiring linear heat or aspirating detection alongside conventional systems
Healthcare and education campuses
Large estates with multi-building networked systems
Heritage and listed buildings
Where wireless or minimally invasive installation is required
Talk to our team
We will walk through your project, scope the work, and quote against what you need.
Fault finding
Inheriting an installation that’s misbehaving? We diagnose, repair and bring to compliance fire alarm systems originally installed by someone else.
Common faults we resolve:
- Detector contamination and end-of-life devices
- Loop faults (open circuit, short circuit, earth faults)
- Battery and charger failures
- Communication faults between networked panels
- Interface module faults to linked systems
- Persistent false alarm activations
- Cause-and-effect programming errors
For one-off fault diagnosis we attend on a chargeable call-out basis. For ongoing peace of mind, fault finding is included in our maintenance contracts. Either way, you get a clear written report with photos of what we found and what we did about it.
Talk to our team
We will walk through your project, scope the work, and quote against what you need.
FRAs
WSD’s core expertise is the design, installation, commissioning and maintenance of fire detection and suppression systems. Fire Risk Assessments themselves are a separate competency, and we arrange them through competent, accredited fire safety professionals we work with regularly.
If you need an FRA alongside a fire alarm installation or upgrade, just let us know. We’ll coordinate the assessment, take the findings into the design process, and implement any system-level recommendations as part of the same project.
Talk to our team
We will walk through your project, scope the work, and quote against what you need.
Maintenance
Every fire alarm we install can be maintained under one of our planned maintenance contracts, alongside the rest of your fire safety systems. Or, if you’ve got an existing system that needs taking over, we’ll survey it, baseline it, and bring it onto our maintenance programme.
Talk to our team
We will walk through your project, scope the work, and quote against what you need.
Standards
All of WSD’s fire alarm work is delivered to current British Standards:
BS 5839-1
Fire detection and fire alarm systems for buildings (non-domestic)
BS 5839-6
Fire detection and fire alarm systems in dwellings
BS 5839-8
Voice alarm systems
BS 7273-1 and BS 7273-3
Code of practice for the operation of fire protection measures
BS 7671
IET wiring regulations
BS 8519
Selection and installation of fire-resistant power and control cable systems
Talk to our team
We will walk through your project, scope the work, and quote against what you need.
Assured, insured & compliant.
WSD holds the accreditations the industry treats as the minimum bar for serious commercial work. Backed by £5m public liability, £10m employers liability, £1m professional indemnity and £5m product liability cover. All work delivered to current British Standards.
Need a fire alarm system designed, installed or upgraded?
We’ll talk through what you need, arrange a site visit if useful, and quote against the actual scope of work. No menu of upsells, no commitment until you’ve seen a proposal.