Fire safety in residential blocks is built on several principles, with compartmentation considered one of the most important. Compartmentation refers to the way buildings are divided into separate, fire-resistant sections. Each section is designed to stop fire and smoke from moving from one part of the building to another.
If these fire barriers are not properly installed or maintained, a small fire can quickly become a major risk. For Residents’ Management Companies (RMCs), knowing how compartmentation works and understanding what can go wrong is vital.
How Are Sections of the Building Compartmentalised?
Flats and communal buildings are designed so that fire can be contained in a limited area. Special building materials and construction methods are used to create fire-resistant walls, floors, and doors. These barriers are usually rated to last for 30, 60, or 120 minutes against fire and smoke.
Common features of compartmentation include:
- Fire-rated doors and walls
- Fire-stopping around pipes, cables, and ducts
- Barriers inside lofts or ceiling spaces
- Fire dampers in ventilation systems
Each of these elements plays a role in holding back fire, giving people time to evacuate or stay safe in their homes, depending on the building’s evacuation strategy. It also allows firefighters time to arrive and tackle the fire safely.
Where Can Compartmentation Fail?
Even well-designed buildings can develop weak points over time. These weaknesses can lead to serious fire safety issues. Some of the most common causes of compartmentation failure include:
- Poor workmanship or incomplete construction
In some cases, fire-resistant barriers are not built correctly in the first place. For example, incorrect materials may be used, or workers may have left gaps around the edges of fire-stopping materials.
- Damage from later works
Building works and seemingly innocuous installations can break the fire seal between compartments. For example, when a contractor drills through a fire-rated wall to run cables and does not reseal it properly, the barrier is left compromised.
- Service penetrations
Holes or gaps made for pipes, wires, or ventilation can create open routes for fire and smoke. These need to be properly sealed with fire-stopping materials, or they will act as escape paths for flames.
- Wear and tear
Over time, seals on fire doors can degrade, or ceiling tiles may shift – especially in older properties. Left unfixed, these small changes can lead to major risks during a fire.
Fire-Stopping Measures in Loft Spaces and Ceilings
Loft spaces and ceiling voids are common problem areas. These hidden spaces can act like chimneys in a fire, quickly spreading flames between flats.
Cavity barriers (used in roof voids and external walls) are meant to stop this. If they are not installed properly (or at all), or are removed during building works, fire can then spread unchecked.
For RMCs, it is important to be aware that any work involving these spaces, such as insulation upgrades or roof repairs, must be checked afterwards to make sure the intended fire protection has not been disturbed.
The Role of Contractors and Accountability
Every contractor who works on your property must follow fire safety rules. Unfortunately, not all do. A new vent installed by a tradesperson who ignores the fire barrier could put the entire building at risk. That is why RMCs must be clear with contractors about fire safety standards. Always ask:
- Have they considered fire-stopping?
- Are they using approved materials?
- Will they provide evidence (e.g. photos, certificates) of fire safety compliance?
It is good practice to keep records of all works completed and to check them after completion. Spot checks or follow-up inspections are recommended, especially after major works.
Inspections and Risk Assessments
Regular inspections and professional assessments should be part of your building’s fire safety plan. Start with a Type 1 Fire Risk Assessment. This is a non-intrusive check of the communal areas. It should highlight any obvious problems such as damaged fire doors or unsealed risers.
In some cases, more detailed surveys may be needed. Hidden issues can lie behind walls, ceilings or risers. If concerns are raised, a more invasive check such as a Type 2 or Type 4 assessment may be required. These involve opening up parts of the building to check the condition of hidden fire barriers.
Routine fire door checks are a legal requirement – depending on the building’s height, door inspections must be carried out regularly as follows:
- Buildings under 11 metres: Communal and flat entrance fire doors should be checked “regularly”.
- Buildings over 11 metres: Communal doors must be checked every 3 months, and flat entrance doors once a year.
The Importance of Record Keeping
All inspections, repairs, and upgrades should be logged. This is not just best practice, it is required by law. Under the Building Safety Act 2022, landlords and RMCs must maintain a “golden thread” of building safety information. This includes fire strategies, inspection reports, and details of any work carried out.
Keeping this information up to date helps prove compliance, ensures continuity, and makes future maintenance easier. It also protects RMC Directors and Officers from any potential legal action.
Common Pitfalls RMCs Should Avoid
Do not assume compartmentation is intact. Even if a building was compliant when built, it may not be now. Even small changes like adding a boiler, fan, or new lighting can easily damage fire protection.
Do not rely on visual checks alone. A walk-through will not always reveal hidden issues. Unless you physically open up ceilings, risers, or service areas, you may miss gaps or damaged barriers.
Do not delay any fixes required – if fire doors are not closing properly, or you spot a hole in a riser, take action immediately. Delays can cost lives.
Best practice involves:
- Scheduling regular fire risk assessments with a qualified expert
- Carrying out regular visual checks on fire doors and common areas
- Requesting intrusive surveys if there is any doubt about the fire barriers
- Working only with trained contractors who understand fire-stopping
- Keeping detailed records of inspections, repairs, and safety updates
Final Thoughts
Compartmentation is a critical safety feature in block of flats. It protects lives, slows the spread of fire, and allows time for help to arrive. But it only works when it’s properly built, regularly inspected, and well maintained.
RMCs have a legal duty and a moral responsibility to keep their buildings safe. Making fire safety a regular part of your management plan is vital.
If you are unsure about the state of your building’s compartmentation, act now – a small check today could prevent a major tragedy tomorrow.
