Walls and floors
Confirm the intended fire-resisting construction is continuous to the correct junctions.
Passive fire protection guide
Fire compartmentation and fire-stopping surveys
Compartmentation limits the spread of fire and smoke. A properly scoped survey examines whether walls, floors, doors, voids and service penetrations are likely to deliver the intended protection.
Building-section guide
Where compartmentation can be lost
A survey follows the fire-resisting line through walls, floors, voids and openings. A small unprotected route through that line can undermine the intended compartment.
Service penetrations
Check pipes, cables, ducts and trays have suitable tested or assessed sealing systems.
Voids and cavities
Look above ceilings and within façades or roof spaces for missing barriers and concealed routes.
Openings and interfaces
Inspect doors, glazing, dampers, access panels and the junction between different systems.
Scope note: The diagram is illustrative. Survey scope, opening-up and acceptance criteria must follow the building evidence, risk and competent professional judgement.
Passive protection
What are compartmentation and fire stopping?
Fire-resisting walls and floors divide a building into compartments intended to contain fire and smoke for a defined period. Fire doors, cavity barriers, dampers, glazing and protected shafts form part of the same system.
Whenever cables, pipes, ducts or joints pass through a barrier, suitable fire stopping should maintain its performance. An unsealed opening, unsuitable foam or poorly supported service can undermine the whole line of protection.
Reasons to investigate
When might a survey be needed?
An FRA may identify signs or uncertainty that justify further investigation. Surveys are also commissioned before or after refurbishment, following repeated service installations, when fire-stopping records are missing, or where design information and actual construction do not agree.
Scope should follow evidence and risk. Government guidance cautions against assuming destructive inspection is always necessary in blocks of flats without grounds for concern.
- Visible unsealed penetrations or damaged barriers
- Unrecorded fit-outs, cable installations or alterations
- Unknown construction in roof voids, risers or concealed spaces
- Change of use or evacuation strategy
- Fire, smoke spread, enforcement concern or repeated defects
- Need to validate remedial works or create a compartmentation register
Define the scope
Visual, intrusive and targeted surveys
A visual survey examines accessible areas and records evident defects. An intrusive survey opens selected ceilings, boxing or finishes to inspect concealed construction. Targeted investigations focus on defined interfaces or risk areas.
The brief should state areas, access, sampling, exclusions, making good, asbestos controls and whether fire doors, dampers or external walls are included.
| Approach | What it can show | Key limitation |
|---|---|---|
| Visual / non-intrusive | Accessible barriers, risers, openings, doors and visible fire stopping | Cannot confirm concealed construction |
| Targeted intrusive | Selected hidden interfaces where evidence indicates concern | Sampling does not prove every unsampled location |
| Comprehensive intrusive | Broader opening-up against a defined compartment line or building scope | Greater disruption, access and reinstatement requirements |
| Type 2 or Type 4 FRA | Intrusive residential FRA scope under a recognised methodology | Not automatically a substitute for a detailed fire-stopping survey |
Useful evidence
What should the report include?
A useful report identifies each defect on drawings or a location-coded register, records photographs and describes why the condition matters. It should distinguish confirmed defects from limitations and recommendations for further investigation.
Priority should reflect life-safety context, evacuation strategy and the importance of the affected compartment—not simply count holes.
- Survey scope, methodology, access and exclusions
- Compartment lines and relevant design information
- Unique defect reference, exact location and photograph
- Defect type, surrounding construction and affected services
- Risk-based priority and recommended next step
- Areas not inspected and confidence or sampling limitations
From finding to closure
Competent repair, evidence and verification
Repairs should be designed and installed as tested or assessed systems suitable for the substrate, opening, service type, movement and required fire resistance. Product labels alone do not establish that a detail is suitable.
Require competent installers, traceable materials, before-and-after records and controlled inspection. Independent verification or sample checks may be proportionate for extensive or high-risk work. Update drawings and the FRA when work changes the evidence base.
Related guidance and support
Continue with premises and local guidance
Choose the closest property guide, then use the relevant London or Surrey route when you are ready to compare local assessment support.
Frequently asked questions
Fire compartmentation and fire-stopping surveys FAQs
Is a compartmentation survey required by law?
The law requires suitable fire precautions and a suitable and sufficient FRA. It does not prescribe a compartmentation survey for every premises, but further investigation may be necessary where the condition or design of passive protection cannot otherwise be established.
What is the difference between compartmentation and fire stopping?
Compartmentation is the wider system of fire-resisting walls, floors and associated elements. Fire stopping is the treatment used to maintain resistance at joints, gaps and service penetrations.
Does a Type 2 or Type 4 FRA include a fire-stopping survey?
It includes a degree of destructive inspection in relevant residential scope, but it is not automatically a comprehensive fire-stopping survey. The brief and methodology must state exactly what is inspected.
Can a survey be completed without opening walls or ceilings?
A visual survey can provide useful evidence about accessible areas, but it cannot confirm concealed construction. Intrusion should be justified, planned and scoped to the risk and evidence needed.
London and Surrey support
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Sources and limitations
Guidance reviewed 3 August 2026
This page provides general information for England. It is not legal advice or a building-specific assessment. Fire Safety Services is independent and is not affiliated with the Government, enforcing authorities, BAFE, NFRAR or IFSM.