The wrong evacuation strategy for your building type could be catastrophic. We examine the critical factors that determine which approach saves lives — and which one doesn't.. The Most Important Decision You'll Make Every residential building in the UK operates under one of two fundamental evacuation strategies: Stay Put or Simultaneous Evacuation. Choosing the wrong one — or failing to implement the right one properly — can be the difference between an orderly, safe response and a catastrophic loss of life. What Grenfell Changed At Grenfell Tower, the Stay Put strategy was maintained for nearly two hours after the fire began. By the time a full evacuation was ordered, escape routes were compromised. The inquiry concluded that the Stay Put advice should have been abandoned far earlier. This tragedy forced a fundamental rethinking of evacuation strategies across the UK. Understanding Stay Put How It Works In a Stay Put building, only the occupants of the flat where the fire originates evacuate. All other residents are advised to remain in their flats with doors and windows closed. The principle relies on: Compartmentation — each flat acts as a fire resistant box Protected escape routes — corridors and stairs maintained as places of relative safety Fire service intervention — the fire brigade fights the fire before it spreads beyond the flat of origin When Stay Put Works Purpose built blocks of flats with full compartmentation Buildings with single staircase where simultaneous evacuation would cause congestion Buildings where all fire doors, cavity barriers, and fire stopping are in good condition Buildings with reliable fire detection in common areas When Stay Put Fails Compromised compartmentation — any breach allows fire and smoke to spread External fire spread — cladding fires bypass compartmentation entirely Single staircase buildings over 18m — new requirements mandate second staircases Defective fire doors — gaps or failed self closers allow smoke migration Understanding Simultaneous Evacuation How It Works When the fire alarm activates, ALL occupants evacuate the building immediately via the nearest safe escape route. This requires: Building wide fire alarm — every flat must have detection linked to a common alarm Adequate escape routes — sufficient staircase capacity for full building evacuation Assembly points — designated external areas for roll call Evacuation management — staff or designated persons to coordinate When Simultaneous Is Required Converted buildings (houses converted to flats) where compartmentation may not be to modern standards Buildings where a Stay Put fire risk assessment identifies that compartmentation is compromised Buildings with a single means of escape where fire could block that route Temporary measure when Stay Put cannot be supported (e.g., during remediation works) The Critical Decision Framework Step 1: Assess Your Building Type Building Type Default Strategy Key Consideration Purpose built flats (post 1991) Stay Put Compartmentation should be to modern standards Purpose built flats (pre 1991) Stay Put Verify compartmentation meets current expectations Converted houses Simultaneous Unlikely to have adequate compartmentation Mixed use buildings Building specific Requires detailed fire engineering assessment Sheltered housing Simultaneous/Phased Vulnerability of residents is a key factor Step 2: Verify Compartmentation Stay Put can only work if compartmentation is intact. This means: All fire doors achieving their rated performance All cavity barriers in place and undamaged All service penetrations properly fire stopped External wall construction not providing a route for fire spread Step 3: Consider Resident Vulnerability Buildings with high proportions of elderly, disabled, or otherwise vulnerable residents may need to consider: Personal Emergency Evacuation Plans (PEEPs) for individual residents Evacuation chairs or refuges for mobility impaired residents Enhanced alarm systems for hearing impaired residents Staff assisted evacuation where residents cannot self evacuate The Interim Measures Challenge When a building's compartmentation is found to be compromised, the Responsible Person faces an immediate dilemma: Switch to Simultaneous Evacuation — requires installing a building wide alarm system (cost: £15,000 £40,000) Implement Waking Watch — 24/7 fire patrol (cost: £5,000 £15,000 per month) Install a common fire alarm — automated detection as a permanent replacement for waking watch (cost: £20,000 £50,000) The Waking Watch Trap Many building managers implement waking watch as a "temporary" measure. Our data shows the average duration of a "temporary" waking watch is 18 months, at an average total cost of £135,000. A fire alarm system paying for itself within 3 9 months. PEEPs: The Legal Requirement Everyone Is Ignoring Since 2023, all residential buildings with a Stay Put strategy must have a process for developing Personal Emergency Evacuation Plans for residents