13 Jan Building fire-safe vertical cities

Peter Stephenson, Fire Safety Solutions Expert, explores passive fire protection and compartmentation for major projects in the Middle East.

The skylines of Dubai, Riyadh, Doha and other regional hubs now read like an index of ‘mega-projects’: high-rise towers, dense mixed-use districts and transit-oriented developments built at extraordinary speed. Behind the architectural ambition we’ve seen many serious fires, including the recent tragic incident in Hong Kong which focuses our attention on robust fire strategies for all buildings. A fundamental requirement for all buildings is the safe egress of all occupants to a place of safety.

A fire strategy should bring together all elements of the building’s fire safety provisions including, but not limited to, active fire protection systems, means of escape, smoke management, firefighting facilities and fire safety management.

As Middle Eastern cities grow ever taller and more complex, the performance of fire-resisting walls, slabs, doors, shafts and firestopping has become as critical as sprinklers and alarm systems — arguably more so, because when passive measures are designed and installed correctly by a third party approved contractor, they prevent a small fire from spreading beyond the room of fire origin and becoming an incident of international concern.

From great fires to modern compartmentation

The idea of using construction to limit fire spread is not new. After catastrophic urban fires in ancient Rome, Emperor Nero and his successors introduced early rules on building spacing and materials to reduce conflagration risk. Centuries later, the Great Fire of London (1666) drove a move away from timber party walls towards masonry fire walls, limits on overhanging storeys and tighter control of street widths. Those historical catastrophes created the first recognisable ‘fire compartment’ thinking at city scale.

In the 20th century, as steel and reinforced concrete allowed buildings to grow taller, codes began to formalise fire-resistance ratings for structural frames, floors, walls and doors. Today, passive fire protection is defined as a set of built-in measures — fire-resisting walls, floors, doors, firestopping, fire dampers and structural protection — tested as assemblies to deliver a defined fire-resistance duration, typically 30–240 minutes.

For high-rise and complex occupancies, that strategy is expressed through compartmentation: dividing the building into cells or fire sections so that any one fire can be contained long enough for people to escape or be defended in place, and for firefighters to intervene.

Why compartmentation matters in vertical cities

In a low-rise warehouse, a fire that breaches one compartment may still be accessible to fire crews from outside. In a 70-storey residential tower or a multi-tower podium complex, the consequences of losing a compartment can be orders of magnitude greater:

• Vertical spread via façades and cavities can bypass multiple compartments in minutes.
• Smoke migration into stairs, lobbies and lift shafts can compromise egress for hundreds of occupants.
• Structural heating of critical members can threaten stability far from the fire’s origin.

Major façade fires have repeatedly demonstrated how quickly a localised fire can become a whole-building event when the façade or cavity systems defeat the underlying compartmentation strategy. More recent fires again raised questions about façade behaviour, evacuation strategies and the robustness of compartmentation in very high-density towers. While often there have not been fatalities, there have been several recent tragedies in vertical cities that are still stress-testing the limits of current codes and practices.

Fundamentals of good passive fire protection

For large and complex projects, the fundamentals of passive fire protection (PFP) can be grouped into a few core elements:

1. Robust compartmentation layout

A credible fire strategy will define:

• Fire compartments to limit fire and smoke to a floor or a portion of a floor;
• Fire sections or zones to protect critical areas: refuge floors, plant rooms, control rooms, egress routes and high-risk occupancies;
• Protection of vertical routes — stairs, lifts, service risers, atria — to maintain tenable egress and firefighting access.

Codes such as the UAE Fire and Life Safety Code require specific areas like emergency command centres to be separated by one-hour fire-resisting compartment walls and floors as a minimum, reflecting their criticality. Similar provisions exist in NFPA-based and national codes across the region.

2. Tested, compatible assemblies

‘Passive’ does not mean ‘simple’. Fire-rated walls, floors, doors, glazing, dampers and firestopping must be:

• Designed and specified as systems matched to tested assemblies;
• Installed strictly in accordance with listings and manufacturer instructions — including fixings, framing, clearances and joint details;
• Compatible with each other, particularly where multiple products interface at penetrations and junctions.

Recent guidance emphasises that inspections for passive protection should verify conformity with the relevant test evidence and standards, not just visual appearance, especially for fire-rated doors and partition systems.

3. Firestopping and cavity barriers that actually work

Firestopping failures are among the most common weaknesses revealed in surveys of existing buildings. A 2023 circular issued by the UAE Civil Defence specifically targeted improvements in firestopping design, engineering judgements, installation and inspection, following federal workshops on enhancing passive fire protection.

Similar concerns have arisen worldwide. The Grenfell Tower Inquiry and related analyses repeatedly highlighted deficiencies in façade cavity barriers and the lack of effective fire breaks behind combustible cladding.

4. Ongoing barrier management

For mega-projects, barrier management — treating fire-resisting walls, floors, doors, dampers and firestopping as a managed asset — is now increasingly seen as best practice. Specialist guidance and NFPA standards (e.g. NFPA 80 for fire doors and dampers) call for regular surveys, repairs and recurring testing intervals (e.g. dampers at commissioning, one year after, then every four to six years depending on occupancy).

In dense mixed-use districts where fit-outs, tenant changes and service upgrades are continuous, this kind of programme is essential to prevent gradual erosion of the original compartmentation design.

Emerging trends and technologies in passive fire protection

Mega-projects in the Middle East are increasingly pushing beyond conventional cast-in-place construction towards modular, prefabricated and industrialised building methods. This shift presents both challenges and opportunities for passive fire protection.

1. Modular and prefabricated volumetric construction

Volumetric modular units, such as factory-built rooms or pods assembled on site, are gaining traction for hotels, student housing, worker accommodation and even mid- to high-rise residential projects. From a PFP perspective, modular construction offers powerful advantages:

• Factory-controlled quality: Fire-resisting walls, floors, ceilings and cavity barriers can be built in controlled conditions, with integrated firestopping around services and structurally robust joints.
• Repeatability: Standardised details for door sets, riser penetrations and junctions can be refined, tested and rolled out at scale.
• Integrated compartmentation: Individual modules can be designed as self-contained compartments, or as part of larger fire sections, using fire-rated boards, composite panels and encapsulation systems purpose-designed for modular construction.

However, several high-profile fires involving modular or prefabricated buildings (such as the Moorfield Hotel fire in Scotland and other modular losses) have highlighted risks where combustible materials, unprotected joints or poorly detailed interfaces allow hidden fire spread. Insurers and regulators now expect modular fire strategies to demonstrate performance at module-to-module joints, corridor connections and façade interfaces, not just within the pod.

For Middle Eastern mega-projects, where modular worker accommodation and remote camp facilities are common, these lessons are particularly relevant.

2. Advanced fire-resisting materials and systems

Manufacturers have developed a wide range of high-performance boards, composite panels and spray-applied or intumescent coatings aimed at both traditional and modular construction. Prominent solutions include:

• Concrete or calcium-silicate-based boards and composite panels used to create slim, highly fire-resisting walls, ceilings, service enclosures and blast-resistant barriers.
• Integrated structural protection systems for steel and modular frames that combine structural fire protection with compartmentation functions.
• Improved cavity barrier and firestop products tailored for modular joints, façade interfaces and penetrations in lightweight assemblies.

For mega-projects, these systems can reduce structural depths, minimise weight and speed installation – critical benefits for super-tall towers and long-span podiums – provided that they are fully supported by test evidence at the required fire ratings and configurations.

3. Digital design, BIM and PFP data

A major emerging trend is the integration of PFP into Building Information Modelling (BIM) and broader digital project workflows:

• Digital fire strategy models can embed compartment boundaries, fire-resistance ratings and door performance requirements directly into the BIM environment.
• Clash detection can be configured to flag services that penetrate rated walls or floors without an associated tested firestop system.
• Asset tagging allows every fire door, damper, firestopped penetration and fire barrier to be assigned a unique ID linked to as-built data, test reports and maintenance history.

This enables a true ‘barrier management system’ at district scale, where multiple towers, podiums, transport hubs and infrastructure elements share interconnected fire strategy data.

4. Smarter inspection and assurance

Codes and guidance are increasingly emphasising verification and competence in passive fire protection:

• Regular inspections of fire doors, walls and partitions to verify function and conformance.
• Greater scrutiny of Engineering Judgements (EJs) for firestopping, especially where project-specific details fall outside tested configurations.
• Use of digital tools, such as tablet-based inspection apps, photo records and asset databases, to support defensible compliance records across mega-projects.

Given the lessons from Grenfell and other façade fires, regulators are also demanding clearer evidence that façade systems, insulation and cavity barriers will perform as a system, not just as individual tested materials.

Codes, lessons learned and the Middle East context

High-rise façade fires in the Gulf, combined with international disasters, have already driven significant changes in codes and practice:

• The UAE Fire and Life Safety Code has been repeatedly updated to tighten requirements on cladding combustibility, façade testing and passive fire protection.
• Other Middle Eastern jurisdictions, including Saudi Arabia and Qatar, have progressively aligned their regulations with international benchmarks (NFPA, IBC, EN standards) while also introducing local façade and high-rise provisions influenced by recent incidents globally and regionally.
• In the UK, the post-Grenfell regulatory overhaul includes bans on combustible cladding in certain high-rise residential applications and a sustained national programme to remove dangerous cladding, with a target to remediate most high-risk buildings by 2029.

Several consistent lessons emerge from inquiries and case studies:

1. Compartmentation must be sacrosanct.
   • Breaches — through cladding, service penetrations, poorly protected shafts or defective doors — rapidly invalidate ‘stay put’ strategies and endanger occupants and firefighters.
2. Façades are part of the compartmentation system.
   • External walls, insulation and cladding cannot be treated as purely architectural or energy-efficiency features; their fire performance must be fully integrated with the fire strategy.
3. Competence and accountability are critical.
   • Failures in design, specification, installation, supervision and maintenance have repeatedly been identified as causal factors, often more than outright absence of regulation.
4. Retrofitting and legacy stock matter.
   • Many tall buildings in the region and worldwide were built to earlier standards. Proactive surveys, façade assessments and PFP upgrades are crucial, especially where combustible cladding or unknown firestopping details exist.

Meeting the demands of mega-projects: practical recommendations

For developers, authorities and design teams delivering major Middle Eastern projects, from branded super-tall towers to giga-projects and tourism cities, the following practices can help ensure that passive fire protection and compartmentation are equal to the ambition of the architecture.

1. Start with a risk-based fire strategy

• Use performance-based fire engineering, where permitted, to understand credible fire and smoke spread scenarios, within compartments, across façades and via cavities and shafts.
• Explicitly define compartmentation philosophy: where fires must be contained, where phased evacuation or defend-in-place is expected, and how fire services will access and operate.

2. Treat façade design as a fire-critical system

• Require façade systems (cladding, insulation, cavity barriers, sub-frame) to demonstrate tested performance as an assembly at relevant scales and configurations.
• Carefully coordinate balcony details, spandrel zones, window-to-slab junctions and corners — common weak points in cladding fires.
• For refurbishment or recladding projects, insist on rigorous intrusive surveys and remediation of existing firestopping and cavity barriers.

3. Integrate PFP into modular and prefabricated strategies

• For modular pods, define whether each module is a compartment or part of a larger compartment, and test joint details accordingly.
• Pre-install as much of the compartmentation as possible in the factory, such as firestopping within pods, rated shafts, risers and service zones, to reduce on-site variability.
• Work closely with insurers and authorities to demonstrate equivalence or superiority of modular PFP performance compared to conventional construction, referencing lessons from past modular fires.

4. Build a barrier management culture

• Create a project-wide PFP register for all fire-resisting construction, linked to the BIM model.
• Implement a structured inspection regime for fire doors, walls, floors, dampers and firestopping, aligned with NFPA and local code requirements.
• Set clear change-management rules so that fit-out contractors, IT teams and MEP specialists cannot compromise rated construction without approved firestopping details and inspections.

5. Strengthen competence and collaboration

• Require demonstrable PFP qualifications and experience for designers, fire engineers, installers and inspectors.
• Encourage early collaboration between architects, structural engineers, MEP designers, façade specialists, fire engineers and Civil Defence/Authority Having Jurisdiction (AHJ).
• Use Qualitative Design Reviews (QDRs) or equivalent structured workshops at key design stages to challenge and refine compartmentation, façade strategy and PFP details across stakeholders.

Passive first, not passive later

The Middle East’s vertical cities and mega-projects are redefining what is possible in the built environment. But the fires that have captured global attention — from Grenfell in London to cladding fires in Dubai and other Gulf cities — have shown that bold architecture without equally bold fire safety thinking is an unacceptable gamble.

Passive fire protection and compartmentation are the backbone of any credible strategy for these developments. They must be:

• Thought about early;
• Treated as critical engineered systems, not decorative finishes;
• Verified through testing, inspection and digital management; and
• Continuously maintained throughout the life of the asset.

If designers, developers, regulators and operators embrace the full potential of modern PFP systems — especially within modular and prefabricated approaches — then the region’s most ambitious projects can also become global exemplars of resilience, not just of height and scale.

This feature appeared in issue 68 of Fire Middle East magazine.