Compartmentation is part of passive fire protection, not the whole of it. Compartmentation divides a building into fire-resisting compartments so that fire and smoke are contained for a defined period. Passive fire protection (PFP) is the umbrella term, also covering fire doors, fire-resistant glazing, structural fire protection, fire-stopping and cavity barriers.
Compartmentation is part of passive fire protection, but PFP covers more than compartmentation alone
Passive fire protection (PFP) is the umbrella term for the building features that resist fire and smoke without active intervention. It includes compartmentation, fire-resistant glazing, structural fire protection, fire-stopping at service penetrations, cavity barriers, fire doors, and more.
Compartmentation specifically refers to dividing the building into fire-resisting compartments so that fire and smoke are contained for a defined period (commonly 30, 60, 90 or 120 minutes). Compartmentation is a major component of PFP but not the only one.
A 'compartmentation survey' usually focuses on compartment lines, while a 'PFP survey' takes a wider view. The right scope depends on what you're trying to evidence, what the building's risk profile is, and what your statutory duties require.
What a compartmentation-focused survey examines
Compartment walls and floors: the physical separation between flats, between flats and common parts, and between common parts and risers / service shafts. Surveyors check construction make-up, continuity, integrity of joints and any breaches.
Service penetrations: where pipes, cables, ducts, lift shafts and other services pass through compartment lines, the integrity of the fire-stopping installed around them. This is one of the most common areas of compartmentation failure in older buildings.
Cavity barriers: in cavity wall construction and at junctions between roof voids and compartmentation lines, cavity barriers prevent the spread of fire and smoke within the cavity. Continuity is critical and often degraded by subsequent works.
Compartmentation between flats and common parts: flat entrance doors, party walls, and the integrity of the line that separates the dwelling from the escape route are key to the building's escape strategy.
What a wider passive fire protection survey adds
Fire doors: surveys of all fire doors in the building - flat entrance doors, common-parts doors, riser doors, plant-room doors. Each is checked against the door's specified fire rating (e.g. FD30, FD60), including the leaf, frame, intumescent seals, smoke seals, hinges, closers and signage.
Fire-resisting glazing: where the building relies on fire-resisting glass (e.g. in vision panels to common parts, in glazed escape lobbies), the glazing's fire rating, framing, and installation details all matter.
Structural fire protection: spray-applied or board-encased protection to steel beams and columns, intumescent paint, concrete cover to reinforcement. Whether this is intact, undamaged and at the specified thickness.
Ductwork fire-stopping: ventilation, smoke extract and air-handling ducts crossing compartment lines need appropriate fire dampers or fire-resisting ductwork. This is commonly overlooked in older buildings and is a common defect.
Fire-stopping generally: not just at compartment lines but at any opening that should be sealed against fire and smoke spread - junctions between elements, holes around fixings, gaps at trades' interfaces.
Choosing between a compartmentation survey and a wider PFP survey
Compartmentation survey is usually the right scope when: a specific compartmentation issue has been identified (e.g. residents reporting smoke spread, a fire risk assessment recommending compartmentation investigation), the building's PFP is otherwise well understood, or budget constrains the scope to compartmentation lines only.
Wider PFP survey is usually the right scope when: the building's PFP record is not well documented, the building falls within the higher-risk regime under the Building Safety Act, recent works have potentially affected multiple PFP elements, or the responsible person needs to evidence comprehensive PFP for their fire risk assessment.
In practice, many instructions are framed as 'compartmentation surveys' but expand to cover fire doors and basic fire-stopping observations because the issues found at compartment lines naturally raise questions about adjacent elements. Scope flexibility at instruction stage avoids needing a second survey shortly after the first.
What the report should give you - and what comes next
The report should: identify each defect with a location reference, describe the defect, state its likely fire-performance implication, recommend a remediation approach (or specialist follow-up if needed), and prioritise it by severity. Generic statements like 'compartmentation appears broadly intact' without location-specific evidence are not adequate.
Remediation work itself is typically carried out by specialist fire-stopping contractors with third-party accreditation (e.g. IFC, FIRAS, BM TRADA). The surveyor's role on remediation is to specify the work, support tender / procurement, and verify completion - not usually to carry out the physical works.
For higher-risk residential buildings under the Building Safety Act, the PFP / compartmentation evidence often feeds directly into the safety case report. Surveys carried out with that downstream use in mind tend to be more useful than surveys carried out as one-off compliance exercises.
Questions visitors commonly ask
Is compartmentation surveying intrusive?
Mostly non-intrusive: visual inspection of compartment lines and accessible service penetrations. Limited opening-up is sometimes recommended where the construction or the fire-stopping is concealed - for example, in service risers, behind dry lining, or above ceilings. Any opening-up is agreed in advance.
How does this relate to the fire risk assessment?
The fire risk assessment (FRA) under the Regulatory Reform (Fire Safety) Order 2005 is the responsible person's overarching assessment of fire risk in the building. A PFP / compartmentation survey provides specialist input on the building's passive fire protection that supports the FRA - it does not replace it.
Who can carry out these surveys?
Competent professionals - typically chartered building surveyors, fire engineers, or specialist PFP consultants. Competence is assessed against the survey type: compartmentation surveying can be carried out by experienced building surveyors; complex fire engineering questions may require a fire engineer.
What's the difference between a compartmentation survey and a fire door inspection?
Fire door inspections focus specifically on each fire door's fire rating, installation, hardware and condition. Compartmentation surveys focus on the compartment walls and floors and the fire-stopping at service penetrations through them. The two are complementary - many buildings need both.
Where this usually links to live instructions
Fire Compartmentation Surveys London
Compartmentation, fire stopping and cavity barrier inspections.
View Fire Compartmentation Surveys LondonPassive Fire Protection Surveys London
Surveys covering compartmentation, fire stopping, cavity barriers, risers, service penetrations and remedial schedules.
View Passive Fire Protection Surveys LondonFire Safety & Facade Consultants London
Parent service combining external walls, compartmentation, fire doors and Building Safety Act work.
View Fire Safety & Facade Consultants LondonManaging Agents
Fire safety advisory for managing-agent portfolios.
View Managing AgentsPrimary sources and further reading
Links checked 18 July 2026. These primary and professional sources provide general context; they do not confirm how the guide applies to a particular building or appointment.
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Fire Compartmentation Surveys
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A competent fire-safety professional should confirm fire-resistance claims, inspection scope, opening-up strategy and how findings may support a fire risk assessment or safety case.
Savas Bulduk
BSc (Hons) MRICS, Director & Chartered Building Surveyor.
Writes on Building surveying, Fire safety and facade, External wall systems, Technical due diligence, Contract administration. See the full team profile.