What is passive fire protection? A guide for subcontractors
By
Marketing Team
@Onetrace
Passive fire protection (PFP) is the part of a building’s fire safety strategy that helps contain fire and smoke, limit their spread, and protect the structure for long enough to support safe evacuation.
The role of PFP has grown considerably in the UK as building safety requirements have tightened and more attention has been placed on how buildings control the spread of fire.
The market reflects this shift.
Barbour ABI estimates that the UK PFP market was worth £947 million in 2024 and forecasts average annual growth of almost 5% through to 2029. That growth also means continued demand for contractors and subcontractors who can deliver compliant, properly documented work.
Whether you’re looking to move into this area, broaden the work your business takes on, or work more smoothly with the teams around you, this guide gives you a practical grounding in passive fire protection.
Key takeaways
Passive fire protection limits fire spread
Compartmentation, fire stopping, and other measures help contain fire and smoke and protect the building’s structure.PFP covers a range of specialist work
Subcontractors may carry out surveys, installations, remedial work, and ongoing maintenance across different building types.Quality and documentation matter
Correct installation, photographic evidence, materials records, certificates, and completion reports help demonstrate that work meets the required standard.PFP subcontractors need more than technical skills
Third-party certification, relevant training, insurance, and client or supply-chain requirements can all play a role, depending on the work and contract.Onetrace brings PFP work into one system
Onetrace helps subcontractors manage surveys, evidence, compliance, project tracking, reporting, and workforce management from one platform.
What is passive fire protection?
Passive fire protection refers to the built-in fire-resisting measures that form part of a building’s construction.
Their purpose is to limit the movement of fire, smoke, and heat, protect key structural elements, and maintain the integrity of defined areas of a building for a specified period. Unlike systems that need to detect a fire or be triggered to respond, passive protection is built-in and designed to perform when exposed to fire.
How does passive fire protection work?
At a basic level, passive fire protection works by slowing the movement and effects of fire through the building. It achieves this through:
Compartmentation: Fire-resistant construction separates different parts of a building so that a fire can be restricted to its area of origin for a defined period.
Fire resistance: Structural elements and protective materials are designed to withstand fire exposure for a set period without losing the performance needed to support the building or maintain separation.
Smoke control: Fire and smoke can travel through gaps, openings, and building cavities. Passive protection limits these routes so smoke is less able to move from the fire compartment into other parts of the building.
Protection of openings and penetrations: Services like pipes, cables, and ductwork often pass through walls and floors. The points where they pass through fire-resisting construction must be protected so they don’t create a route for fire and smoke to spread.
Protection of joints and interfaces: Gaps between building elements can also weaken a fire-resisting barrier. These joints and interfaces need suitable protection to maintain the required performance of the overall construction.
This is why passive fire protection is more than just adding fire-resistant materials to a building. The protection needs to work as a continuous system, with the right level of fire resistance maintained wherever the building is divided, penetrated, or joined.
What are the main types of passive fire protection?
Passive fire protection covers a range of building elements and specialist systems. The right combination depends on the building, its use, and its fire strategy.
The main types a subcontractor is likely to encounter in UK projects include:
PFP type | What it does | Where it’s applied |
Fire doorsets | Maintain a fire-resistant barrier at openings while helping to limit the spread of fire and smoke between areas | Doorways in compartment walls, corridors, stairwells, and other protected routes |
Fire-resistant walls and floors | Form fire-resisting barriers that separate parts of a building and restrict fire and smoke from moving between compartments | Compartment walls, floors, ceilings and other separating elements |
Fire stopping | Seals gaps, joints, penetrations, and service openings so they don’t compromise a fire-resisting construction | Around pipes, cables, ducts, and other services passing through walls and floors |
Cavity barriers | Break up concealed cavities and stop fire and smoke from spreading through hidden spaces | Wall cavities, ceiling voids, roof spaces, and other concealed construction |
Intumescent coatings | Expand when exposed to high temperatures, forming an insulating layer that slows the heating of the material beneath | Structural steelwork and other load-bearing elements that require additional fire resistance |
Fire-resistant glazing | Provides a transparent fire-resisting barrier while allowing light and visibility through a wall, door, or partition | Fire-rated windows, doors, screens, and glazed partitions |
Fire and smoke dampers | Close or restrict airflow through ductwork to help prevent fire and smoke from travelling between compartments | Heating, ventilation, and air-conditioning systems where ducts pass through fire-resisting construction |
Fire curtains | Form a temporary fire-resisting barrier across an opening when deployed, helping to constrain fire and smoke movement | Open-plan areas, atria, and other locations where a conventional fire-resisting barrier may not be practical |
What’s the difference between active and passive fire protection?
The main difference between active and passive fire protection lies in how each responds to a fire.
Active fire protection relies on detection, activation, or human intervention to address an incident. Common examples include fire alarms, smoke detection, and sprinkler systems.
Passive fire protection, by contrast, is built into the building and doesn’t normally need to detect a fire or be switched on before it can perform its intended function.
In practice, however, it’s rarely a question of choosing one over the other, as a building’s fire strategy will typically use passive and active measures together. Importantly, both systems need to be properly designed, installed, inspected, and maintained to provide the intended level of protection.
Why is passive fire protection important?
The value of effective PFP goes beyond meeting a specification. When it’s designed and installed correctly, it supports several important outcomes:
Saving lives: By slowing the spread of fire and smoke, PFP can help keep escape routes usable for longer and give occupants more time to reach safety.
Protecting the structure: Fire can weaken structural elements as temperatures rise. Maintaining their fire resistance for the required period can help reduce the risk of premature structural failure.
Limiting damage: Restricting a fire to a smaller part of a building can reduce the extent of damage and help protect areas that haven’t been directly affected.
Keeping businesses running: A serious fire can disrupt operations long after the fire itself has been dealt with. Limiting damage can reduce downtime, the loss of usable space, and the knock-on impact on staff, customers and tenants.
Protecting your reputation as a subcontractor: Reliable workmanship, clear records, and consistent compliance can help build trust with main contractors, facilities managers, and other clients.
Supporting compliance: UK building regulations set requirements for limiting the spread of fire and smoke, including the use of fire-resisting construction and suitable fire stopping at joints and service penetrations. The Building Regulations 2010, through Approved Document B, also require concealed spaces to be designed and constructed to inhibit the unseen spread of fire and smoke.
Passive fire protection subcontracting: Work, requirements, and documentation
Here’s what you need to know about working as a subcontractor in passive fire protection.
What work does a passive fire protection subcontractor carry out?
The scope can vary by project, but a passive fire protection subcontractor’s typical work includes:
Surveys and inspections: Subcontractors assess existing passive fire protection to establish its condition, identify defects, and check whether the building’s fire-resisting construction is still performing as intended. The scope can range from a passive fire protection survey covering the building’s overall PFP provision to more focused checks like fire stopping inspections or fire door surveys.
Installation: On new-build and refurbishment projects, subcontractors install the specified PFP measures and ensure they’re fitted in line with the relevant design and system requirements. Depending on their scope, this can include fire stopping, compartmentation, fire doors, and protective coatings for structural elements.
Remedial work: When surveys or inspections uncover defects, subcontractors put the protection back into the required condition. This may involve repairing damaged fire-resisting construction, sealing unprotected service penetrations, restoring compartmentation, or addressing defects in fire doors and other installed protection.
Maintenance: Existing PFP needs to remain effective throughout the building’s life, so subcontractors may carry out routine checks, repairs, and maintenance as part of ongoing fire safety management. This can also include updating protection when building work changes the original construction.
Where is passive fire protection work carried out?
Passive fire protection is needed across a wide range of UK buildings, so subcontractors can work on everything from occupied public buildings to industrial sites.
Typical work locations include:
Commercial and office buildings: Commercial premises are a common setting for PFP work, particularly during fit-outs, when new services and partitions can breach compartmentation and fire doors, and penetration seals need to be installed, inspected, or upgraded.
Public and healthcare buildings: Schools, colleges, NHS buildings, and other public facilities require passive protection suited to buildings that may be occupied throughout the day.
Residential buildings: Flats, apartment blocks, and other residential buildings rely on passive protection to separate dwellings and protect shared areas and escape routes.
Industrial and warehouse sites: Factories, warehouses, and other industrial buildings can present different fire risks because of their size, layout, stored materials, and processes. PFP work there may form part of new construction, alterations, or efforts to restore compartmentation in existing premises.
Refurbishment and existing buildings: A significant amount of subcontracting work takes place in buildings that are already in use. Surveys can identify defects or missing protection, after which subcontractors carry out remedial work to restore the building's intended fire performance.
What qualifications and accreditations do PFP subcontractors need?
There’s no single qualification or accreditation that every PFP subcontractor in the UK must hold. The requirements depend on the type of work being carried out, the project, and the client or main contractor.
For specialist PFP work, third-party certification is an important way for subcontractors to demonstrate competence and give clients confidence in their installation and quality-control processes. For example, FIRAS is a voluntary, UKAS-accredited certification scheme covering the installation and maintenance of a wide range of passive fire protection systems.
Alongside specialist certification, clients may ask subcontractors to provide the following:
Relevant technical training and competence for the work being carried out
Public liability or employers’ liability insurance
Client or supply-chain accreditations, such as CHAS or SafeContractor
Management-system certifications, such as ISO 9001 or ISO 45001
What documentation do PFP subcontractors need?
Proper documentation is a key part of passive fire protection work. It provides a traceable record of what was completed and helps clients verify that the work meets the required standard.
Depending on the project and scope, subcontractors may need to provide:
Risk assessments and method statements (RAMS)
Materials records, recording the products and materials used
Certificates and test results, where required for the systems or products installed
Completion reports, confirming what work was carried out
Photographic evidence, showing the completed installation and relevant details
A simple way to keep fire protection documentation and other relevant subcontractor documents organised and consistent is to use passive fire protection software like Onetrace.
How Onetrace helps passive fire protection subcontractors
Onetrace is a construction management platform built for subcontractors and used by over 1,000 subcontracting businesses. It started in passive fire protection, which gave it a strong understanding of the way PFP work is surveyed, installed, inspected, documented, and handed over.
That’s why PFP subcontractors can rely on Onetrace for various tasks throughout the full project lifecycle, including:
Surveys and inspections: Create job-specific digital forms with structured fields, checklists, photographs and mandatory information. Forms can be standardised across projects while conditional fields and auto-fill options reduce unnecessary work on site.
Installation and remedial work: Use custom forms to capture work consistently, including photographs, materials, and job details. Operatives can record work against specific locations and drawings, creating a reliable record of what was completed and where.
Evidence and compliance: Capture before, during, and after photographs and keep supporting documentation in one place. Onetrace can also manage signed RAMS, health and safety documents, and other compliance records, with an accurate history of who has viewed or signed them.
Project and site tracking: Upload drawings and organise them by blocks, levels, and zones, allowing operatives to place pins against the right location. This gives managers a structured view of where work has been completed and makes it easier to filter and report on specific areas.
Quality assurance and approvals: Build approval stages into the workflow so submitted work can be reviewed, accepted, or rejected with feedback. Approval histories provide a record of decisions and can help identify recurring issues before they become late-stage snags.
Reporting and handover: Generate branded PDF and Excel reports using project data, job sheets, drawings, locations, photographs, and materials. This gives clients and auditors a structured record of completed work and can reduce the manual effort involved in preparing handover information.
Materials and cost tracking: Record the materials used on each job, including quantities, costs, and dimensions, with material rates feeding into project costs. This gives you greater visibility of material spend and supports more accurate cost reporting and invoicing.
Site and workforce management: Plan work through the visual Planner, assign operatives to projects, and keep schedules up to date across the office and mobile app. Timesheets also give managers visibility of hours and attendance across teams and projects.
Ongoing maintenance and traceability: QR codes can link physical work to its digital record, allowing future operatives to scan a location and access its previous survey, installation, or maintenance history. This feature is particularly useful where PFP assets need to be revisited over time.
To learn more about these features, schedule a personalised demo with the Onetrace team. We’ll walk you through the platform and how it can fit into your day-to-day PFP work.
FAQ
What does passive protection mean?
Passive protection means built-in measures that help contain fire, smoke, and heat without needing to be activated.
What is a passive fire protection system?
A passive fire protection system is a combination of fire-resisting building elements designed to restrict fire and smoke spread and protect the building’s structure.
Are sprinklers an active or passive fire safety system?
Sprinklers are an active fire safety system because they activate in response to heat from a fire.
What are some examples of passive fire protection elements?
Some examples of passive fire protection elements are fire doors, compartment walls and floors, fire stopping, cavity barriers, fire-resistant glazing, intumescent coatings, dampers, and fire curtains.
What are some effective passive fire protection strategies?
Effective passive fire protection strategies include maintaining compartmentation, protecting service penetrations and joints, using suitable fire-resisting construction, and ensuring protection is correctly installed, inspected, and maintained.
Marketing Team
@Onetrace
The Onetrace marketing team is passionate about sharing insights, ideas, and innovations that help construction businesses stay connected, compliant, and efficient. Combining industry expertise with a love for clear communication, we aim to deliver content that empowers professionals to work smarter and safer.