A fire strategy is the document that says how this particular building is supposed to behave in a fire: how people leave, how the fire is contained, how the fire service fights it, and which systems the answers depend on. New buildings get one at design stage. Older buildings often have none, which is why their fire risk assessments keep running into questions nobody can answer.
What a strategy document contains
The occupancy and use. The evacuation strategy, simultaneous or phased or stay put, and the basis for it. Escape route capacity and travel distances. Compartment lines, drawn. The detection and alarm category. Suppression if any. Smoke control. Fire service access, risers and firefighting shafts. Structural fire resistance. And the management arrangements the design assumes, which is the part buildings drift away from first.
Why an existing building needs one
Because the fire risk assessment has to judge whether the precautions are adequate, and adequate compared to what. Without a strategy the assessor is reverse engineering the designer's intent from what is on site. On a building that has been extended, subdivided and refitted several times, producing a strategy is often the cheapest way to stop paying for the same uncertainty in every assessment.
What a fire engineer does that an assessor does not
A fire risk assessor judges a building against established guidance. A fire engineer analyses it from first principles, using calculation and modelling, and can justify a design that departs from the guidance: an atrium, a long travel distance, an unusual occupancy, a listed building where the standard answer is impossible. That is what the discipline is for, and it is also why engineered solutions depend on the management assumptions in the strategy holding true for the life of the building.
Where it bites commercially
Change of use, subdivision of a floor, a new mezzanine, converting offices to residential. Each changes the occupancy the building was designed for, and building control will ask how the strategy still works. Having the document already, and updating it, is far cheaper than commissioning one under the pressure of a stalled project.
Questions people ask about fire strategy
What is a fire strategy?
The document describing how a building is intended to perform in a fire: evacuation, compartmentation, detection, suppression, smoke control and fire service access, with the reasoning behind each.
Is a fire strategy a legal requirement?
Not by name in the Fire Safety Order. It is normally required through Building Regulations for new work, and in existing buildings it is what makes a defensible fire risk assessment possible.
What is the difference between a fire engineer and a fire risk assessor?
An assessor judges a building against established guidance. An engineer analyses it from first principles and can justify a design that departs from the guidance.
When does a building need a new strategy?
On a change of use or occupancy, subdivision, extension, or any alteration that changes the assumptions the original strategy rested on.