Fire compartmentation is the invisible backbone of building fire safety. But surveys reveal that 78% of UK buildings have compartmentation deficiencies. Your building is almost certainly one of them.. The Invisible Shield That's Failing Fire compartmentation divides a building into fire resistant cells — compartments — that contain fire and smoke to the area of origin, giving occupants time to escape and firefighters time to respond. When compartmentation works: Fire is contained within one flat. Other residents are safe behind their fire rated walls, floors, and doors. The stay put strategy succeeds. When compartmentation fails: Fire and smoke spread through walls, floors, service penetrations, and hidden voids. The entire building becomes involved. People die. The Alarming Evidence A 2024 analysis of 500 compartmentation surveys across UK buildings found: 78% had at least one significant compartmentation deficiency 34% had deficiencies rated as 'high risk' Average number of deficient penetrations per building: 47 Most common location: service risers and plant room boundaries Average age of oldest unprotected penetration: 12 years Common Deficiencies 1. Service Penetrations (42% of all deficiencies) Cables, pipes, and ducts passing through fire rated walls without fire stopping Trades cutting through fire barriers and not reinstating Incorrect fire stopping products — builders' foam instead of fire rated sealant 2. Structural Junctions (18%) Gaps between floor slabs and curtain wall facades Missing cavity barriers at floor to wall junctions Compartment walls not continuing to the structural soffit 3. Fire Doors (15%) Oversized gaps allowing smoke passage Missing or damaged intumescent strips Self closers removed or defective 4. Dampers (12%) Fire dampers in HVAC ducts not installed or not maintained Access panels for damper inspection missing or inaccessible Dampers seized open due to lack of maintenance 5. Building Modifications (13%) Unauthorised works breaching compartment walls IT installations creating cable routes through fire barriers Building extensions not properly fire separated The Solution: Compartmentation Surveys Type 1 (Non Destructive) Visual inspection of accessible elements. Limited in scope but provides initial risk assessment. Type 2 (Sampling) Destructive inspection of representative sample areas. Removes ceiling tiles, opens access panels, and inspects hidden spaces. Type 3 (Comprehensive) Extensive destructive inspection of all accessible areas. Provides the most complete picture but is disruptive and costly. Magnus Opifex conducts compartmentation surveys across all building types. Contact us.