Fire safety in a shared building is rarely one person’s job. A multi-tenant commercial building has an owner, a managing agent, and occupiers who each control their own space, so the duty is split between them. The owner or managing agent looks after the communal areas and shared escape routes, while each occupier is responsible for fire safety inside their own unit, and where that control overlaps, the law expects everyone to cooperate.
Who Is the Responsible Person in a Multi-Tenant Commercial Building?
Under the Regulatory Reform (Fire Safety) Order 2005, the responsible person is whoever has control of the premises. With a single occupier that is straightforward. In an office block, business park, or mixed-use building with several tenants, it splits.
- The building owner or managing agent is the responsible person for the communal areas, shared escape routes, and the parts of the building with no single tenant controls.
- Each occupier is the responsible person for their own demised area, covering the hazards and equipment inside their unit.
When more than one responsible person has duties in the same building, the Order requires them to cooperate and coordinate, so nothing is missed at the boundaries. That duty to work together is written into legislation, not just good practice.
If your building also contains domestic premises, such as flats above ground-floor retail or offices, the Fire Safety Act 2021 confirms the assessment must take in the structure, external walls (including cladding, balconies, and windows), and the entrance doors between those flats and the common parts. This clarification applies to buildings with two or more sets of domestic premises, so it is relevant to mixed-use blocks rather than purely commercial ones.
What Does a Fire Risk Assessment Cover in a Shared Occupancy Building?
A shared-occupancy building is assessed on more than one level, and the levels need to line up.
In the communal areas, the assessment looks at:
- Escape routes and how easily people can leave
- Fire detection and the means of raising the alarm
- Emergency lighting and fire doors
- Signage, fire extinguishers, and general housekeeping
Across the building as a whole, it considers compartmentation, how a warning reaches every occupant, and the evacuation strategy. At unit level, each assessment covers the specific hazards inside that unit. A commercial fire risk assessment works only when the building-wide and unit-level views line up.
How Often Should a Multi-Tenant Fire Risk Assessment Be Reviewed?
As a general rule, review the assessment once a year. Higher-risk buildings may need it more often. Beyond the annual cadence, the Order requires a review whenever there is a significant change to the building or how it is used. That word, significant, comes from the legislation itself, so the trigger is a real change to the fire risk profile, not a minor tweak.
In a multi-tenant building, several changes should bring the review forward:
- A change of use in a unit. When a tenant changes what they do, a quiet office becoming a busy food outlet, the fire risk profile changes with it. A new tenant should also be handed the current assessment, showing what has been identified and when the next review is due.
- Building alterations, refurbishment, or a new layout. These can affect compartmentation and escape routes, so the assessment needs to match the building as it now stands.
- A change to the means of escape. Escape routes are central to the evacuation plan, so if one is altered or obstructed, the assessment’s assumptions no longer hold and it has to be revisited.
- A fire or a near miss. Either shows the current arrangement did not work as intended, a clear prompt to reassess.
Our guide on how often a fire risk assessment needs reviewing covers the full list. In a building with tenants turning over, staying on top of those dates is the hardest part.
Why Multi-Tenant Buildings Need a Coordinated Approach
When each tenant arranges their own assessment in isolation, the boundaries between units and communal spaces get missed. The shared escape routes everyone depends on can end up assessed by everybody and nobody at once. That is where a coordinated assessment earns its place, and why we assess the building as a whole and coordinate with the individual tenants. You can read more about what happens if you skip a fire risk assessment at any level.
Reviews are often booked alongside fire alarm testing for a single visit, we work out of hours and at weekends at no extra charge, and we track your review schedule so you know what is due. For landlords and managing agents with several buildings, multi-site pricing keeps the whole portfolio on one plan.
Arrange a Fire Risk Assessment for Your Multi-Tenant Building
If you manage an office block, business park, or mixed-use building with multiple tenants, we can assess the whole site and coordinate with your tenants so nothing falls between the cracks. Our network of 200+ fully accredited, DBS checked engineers covers the UK and Ireland, with out-of-hours availability and multi-site pricing for larger portfolios.
To get started, request a quote and we will build a schedule that keeps your building compliant.
Michael Kiddle
Managing Director of Hawkesworth and a nationally recognised leader in electrical and fire safety, Michael (GIFireE) directs one of the UK's leading compliance companies, safeguarding thousands of businesses each year. Through his voluntary Safe Home Initiative, he has identified and removed thousands of dangerous household appliances from vulnerable people's homes, replacing each one with a safe alternative free of charge.
