Every block of flats has an evacuation strategy: the plan for what residents should do if there is a fire. Getting it right depends on how well the building can contain a fire.
Stay put
Most purpose-built blocks of flats are designed for a stay put strategy, also called defend in place. Each flat is a fire-resisting compartment. If there is a fire in one flat, the people in that flat leave, and everyone else can usually stay in their own flat unless they are affected by heat or smoke, or told to leave by the fire and rescue service.
Stay put only works when compartmentation is effective: walls and floors that resist fire, sound fire doors, and fire-stopped service penetrations. That is why buildings with a stay put strategy usually have no communal fire alarm, which would cause everyone to leave at once.
Simultaneous evacuation
In a simultaneous evacuation strategy, everyone leaves when the alarm sounds. This is used where compartmentation cannot be relied on, for example in some converted buildings, or in buildings found to have serious defects such as combustible external walls. It needs a communal fire alarm that warns every resident.
Temporary changes and waking watch
When serious defects are found, a building may move temporarily from stay put to simultaneous evacuation while the defects are fixed. Historically this was often supported by a waking watch: trained people patrolling the building to raise the alarm. Installing a common fire alarm system is now usually preferred to a long-term waking watch, as it is more reliable and usually cheaper over time.
Evacuation alert systems
Since December 2022, new residential buildings in England with a storey at 18 metres or more must have an evacuation alert system designed to BS 8629. It lets the fire and rescue service sound an alarm in specific parts of the building, or the whole building, if they decide a stay put strategy needs to change during an incident.
When the strategy should be reviewed
- After a fire risk assessment or external wall appraisal identifies significant defects.
- After building work that affects compartmentation.
- When residents' needs change, for example where people would need help to evacuate.
The strategy belongs in the fire risk assessment and, for higher-risk buildings, the safety case.
This guide is general information about UK fire safety law and standards, not legal advice for a specific building. If you are unsure what applies to yours, ask us or a qualified adviser.