Compartmentation is what stops a fire in one part of a building spreading quickly through the rest of it. Walls, floors and fire doors divide a building into fire-resisting compartments that hold back fire and smoke, protecting escape routes and buying the time people need to get out. A compartmentation survey checks that those barriers are actually intact, because a single hidden breach can quietly undermine the whole fire strategy.
Mast Safety carries out compartmentation surveys for building owners, managing agents, landlords and employers, giving you a clear, evidenced picture of where your compartmentation holds and where it has been compromised, along with a practical route to putting it right.
Why compartmentation matters
Most fire strategies rely on compartmentation holding. In residential blocks with a stay-put policy in particular, the assumption is that a fire can be contained within the flat where it starts. If a wall or floor has been breached, often by cabling, pipework or ductwork installed long after the building was finished, that assumption no longer holds, and fire and smoke can spread through the concealed routes nobody can see.
The responsible person has a duty under the Regulatory Reform (Fire Safety) Order 2005 to maintain the building's fire precautions, and compartmentation is a fundamental part of that. It is also an increasingly common finding in fire risk assessments, where a recommendation for a dedicated survey is the usual next step.
What a compartmentation survey covers
We survey the elements that form and protect your building's fire compartments, on a genuine site visit rather than from a desktop review. That includes:
- Compartment walls and floors: the fire-resisting barriers that divide the building, and their continuity.
- Service penetrations: where cables, pipes and ductwork pass through compartment lines, and whether they are correctly sealed.
- Concealed spaces: voids above ceilings, service risers and ducts where breaches are most often hidden.
- Fire doors: as part of the compartment line, checked for their contribution to containment.
- Fire dampers: within ductwork that crosses compartment boundaries, where applicable.
- Gaps and breaches: any opening that would let fire or smoke pass between compartments.
Intrusive and non-intrusive surveys
Compartmentation can be surveyed to different depths. A non-intrusive survey assesses what can be seen without opening anything up, which is quicker and less disruptive but cannot see into concealed spaces. An intrusive survey involves opening up ceilings, risers and voids to inspect the areas where breaches most often hide, giving a far more complete picture. The right level depends on your building, its risk profile and what your fire risk assessment has recommended, and we will advise on which is appropriate rather than over-specifying work you do not need.
From survey to fire stopping
Finding a breach only helps if it gets sealed. Where a survey identifies compartmentation failures, we can specify and carry out the fire stopping needed to restore the barriers, so you move from survey to sealed without sourcing a separate contractor. A compartmentation survey also follows on naturally from a Fire Risk Assessment, and sits alongside our fire door inspections, since fire doors are part of the compartment line. You can see how we combine these into one coordinated programme in our residential portfolio case study.
A report you can act on
You receive a structured survey report identifying every breach we find, its location and the remedial work needed, set out as a prioritised, risk-rated action plan. That gives you a clear order of work, the evidence to show your compartmentation has been assessed competently, and a document that sits alongside your fire risk assessment as part of your fire safety record.
Arrange a compartmentation survey
Tell us about your building and we will arrange a compartmentation survey at the right level for its risk, with as little disruption as possible. You will get a clear, prioritised report and, where breaches are found, a route to sealing them with the same team. From a single building to a whole portfolio, call us, send a message or drop us an email, and we will come back to you, usually the same working day.
Compartmentation Surveys — Frequently Asked Questions
Got a question?
Speak to one of our Health & Safety advisors today
Visit our contact page for more details
Monday-Friday 8.00 am to 5.00 pm