High-Rise Fire Risk Assessment Post-Grenfell Compliance

Service risers, lift shafts, and stairwell voids create continuous vertical pathways that can facilitate rapid fire and smoke spread from floor to floor. Unlike low-rise buildings, high-rises face catastrophic consequences if vertical fire spread occurs—potentially trapping residents on multiple floors simultaneously. Penetrations through floors for electrical cables, plumbing, ventilation, and communication systems often compromise fire compartmentation if not properly sealed.

The Grenfell Tower tragedy revealed catastrophic risks posed by combustible external wall systems, particularly ACM (Aluminium Composite Material) panels with polyethylene cores. Government data shows thousands of UK buildings still require cladding remediation. Buildings with non-compliant external walls typically require EWS1 forms for mortgage purposes, face property devaluation, and may need interim safety measures like waking watches costing £30,000+ monthly until remediation completes.

High-rise buildings rely on mechanical pressurization systems to maintain smoke-free escape routes and firefighting access during emergencies. These systems create positive air pressure in stairwells and lobbies, preventing smoke ingress from adjacent areas. System failures—due to inadequate maintenance, poor design, or door propping—can render stairwells unusable during evacuation, trapping residents. UK regulations now mandate monthly inspections of firefighting lifts and associated smoke control systems under Fire Safety (England) Regulations 2022.

Post-Grenfell, many high-rise buildings transitioned from stay-put to simultaneous evacuation strategies, creating confusion among residents unfamiliar with changed procedures. Simultaneous evacuation of hundreds of residents creates stairwell congestion, extended evacuation times, and challenges for mobility-impaired occupants. Buildings designed for stay-put may lack adequate stairwell capacity for simultaneous evacuation. Government statistics show only 58% of fire safety audits achieve satisfactory ratings—partly due to inadequate evacuation planning and resident engagement.

Buildings over 18 metres must provide at least one firefighting lift with protected lobby access per BS EN 81-72 standards. These specialized lifts enable fire crews to transport equipment to upper floors during emergencies—essential for effective firefighting in tall buildings where stairwell access is impractical. Recent regulations also mandate evacuation lifts per BS 9991:2024 to assist mobility-impaired residents. Lifts serving dual firefighting and evacuation roles must undergo monthly safety checks, with faults reported immediately to fire and rescue services.

Effective compartmentation is fundamental to stay-put evacuation policies in high-rise buildings—each flat must function as a fire-resistant compartment containing fire and smoke within the unit of origin. However, compartmentation commonly fails due to service penetrations (cables, pipes), missing or damaged fire-stopping materials, compromised fire doors, or building alterations that breach fire barriers. Government data shows compartmentation deficiencies as the primary cause of vertical fire spread in high-rise incidents. Buildings with compromised compartmentation cannot safely maintain stay-put policies.