Fire Strategy Reports for Existing Buildings

Why Existing Buildings Need Fire Strategies

The majority of the UK's building stock predates modern fire safety standards. Buildings constructed before the 1980s were designed to a regulatory framework that is now significantly out of date, and many buildings from the 1980s and 1990s used materials and construction methods that would not be permitted under current standards. The Building Safety Act 2022 has brought the fire safety position of existing buildings — particularly higher-risk residential buildings — under unprecedented scrutiny, and the demand for fire strategies for existing buildings has never been greater.

Triggers for Fire Strategies in Existing Buildings

There are several distinct circumstances in which an existing building may require a fire strategy:

• Building Safety Act registration — all existing higher-risk buildings (over 18 metres or seven storeys with at least two residential units) must be registered with the Building Safety Regulator and must have a building safety case. Where no original fire strategy exists, a retrospective fire strategy is required. This is the single largest driver of demand for existing building fire strategies.
• Major refurbishment — any significant work to an existing building that affects means of escape, compartmentation, structural fire protection, or external wall construction triggers the need for a fire strategy. The fire strategy must address the building in its proposed post-refurbishment condition, not just the elements being changed.
• Change of use — where a building changes its occupancy classification — for example, from offices to residential, or from a single occupancy to a house in multiple occupation — a fire strategy is required to demonstrate that the new use can be accommodated safely within the existing structure.
• Sale and due diligence — purchasers of commercial and residential investment properties increasingly require fire strategy documentation as part of technical due diligence. For higher-risk buildings, this is now effectively mandatory given the building safety case requirements.

Challenges of Fire Strategies for Existing Buildings

Producing a fire strategy for an existing building is fundamentally different from producing one for a new building. For a new building, the fire engineer works from design drawings and can shape the design to achieve compliance. For an existing building, the fire engineer must work from the building as it stands — which means establishing the facts about the building through a combination of documentary research and physical inspection.

Common challenges include: limited or no original design documentation; alterations made without building control approval; materials and construction methods that are difficult to identify without intrusive investigation; compartmentation that has been compromised by service installations or alterations; and fire safety provisions that do not meet current standards but may be acceptable as existing provisions under a risk-based assessment.

Approaches to Existing Building Compliance

Fire strategies for existing buildings do not require the building to meet current new-build standards in all respects. They assess the building against the standards applicable at the time of construction, identify where current standards differ materially, and apply a risk-based approach to determine which deficiencies represent an unacceptable risk and which can be managed through operational measures or accepted as tolerably non-compliant.

Where significant deficiencies are identified, the fire strategy will recommend remediation measures, prioritised by risk. This allows building owners to address the most significant issues first and to plan longer-term works on a managed basis, rather than being confronted with an undifferentiated list of non-compliances.