When Is a Fire Risk Assessment Required for Flats?

A fire risk assessment is a legal requirement for most multi-occupied residential buildings in the UK — including flats and blocks of flats — where there are common areas or shared spaces. Understanding when a fire risk assessment is required, what it must cover, and who is responsible is essential for compliance and safety.

This guide explains the legal duties under the Regulatory Reform (Fire Safety) Order 2005 (FSO), how the Fire Safety Act 2021 and Fire Safety (England) Regulations 2022 affect fire risk assessments for flats, and practical triggers for when assessments must be carried out or updated.

In short: a fire risk assessment is required for buildings with two or more flats where any common parts exist.

What the Law Says: When a Fire Risk Assessment Is Required

Fire Risk Assessment Duty Under the Fire Safety Order

Under the Regulatory Reform (Fire Safety) Order 2005, a fire risk assessment must be carried out where a building contains two or more domestic premises and has shared or common parts such as hallways, staircases, lifts, corridors, landings or entrance foyers. This duty applies to residential buildings in England and Wales.

The FSO places the responsibility on the Responsible Person — typically the building owner, freeholder, landlord, managing agent, or entity with control of the premises — to ensure that a suitable and sufficient fire risk assessment is carried out and kept up to date.

The Impact of the Fire Safety Act 2021

The Fire Safety Act 2021 clarified and strengthened existing duties by confirming that a fire risk assessment for multi-occupied residential buildings must consider:

• The structure of the building
• External walls, including cladding, balconies and windows
• Individual flat entrance doors that open onto common parts

This means that these elements must be included in the scope of a fire risk assessment where the building has shared areas — which is virtually always the case for blocks of flats.

Additional Duties Under the Fire Safety (England) Regulations 2022

The Fire Safety (England) Regulations 2022, which came into force on 23 January 2023, supplement the Regulatory Reform (Fire Safety) Order. They impose additional duties on Responsible Persons of multi-occupied residential buildings — primarily based on height and risk profile.

Multi-Occupied Residential Buildings (All Heights)

For all buildings containing two or more domestic premises:

• Responsible Persons must provide residents with relevant fire safety instructions and information.

Buildings Over 11 Metres (Higher-Risk)

If a building is over 11 metres high or has seven or more storeys:

• The Responsible Person must carry out more frequent proactive checks on fire doors in communal areas (e.g., quarterly communal checks and annual flat entrance door checks).

For high-rise residential buildings (often defined as over 18 metres high or with seven storeys):

• Additional commissioning and reporting duties apply, including sharing building plans and fire safety information with the local fire and rescue service.

These regulations do not replace the fire risk assessment duty — they enhance the practical measures that must be monitored and recorded as part of fire safety management in those buildings.

If you’re responsible for a block of flats and are unsure whether your current assessment reflects these duties, a professional review can confirm compliance before enforcement issues arise.

Flats and Maisonettes: When Exactly a Fire Risk Assessment Is Required

Blocks of Flats / Multi-Occupied Buildings

A fire risk assessment is required if a building contains two or more flats with shared common areas — regardless of whether it is purpose-built, converted, rented, leasehold, freehold or mixed use. This applies even if commercial premises occupy part of the building.

The assessment must take into account the safety of people who live in the flats, visitors, contractors, and anyone else lawfully on the premises.

Small Blocks of Flats

For smaller blocks of flats (e.g., up to three storeys with a small number of units), the same basic duty applies — but the scope of the assessment can be proportionate to the risks posed by the premises. UK government guidance confirms that small blocks must still be subject to a fire risk assessment covering common parts and relevant fire safety measures.

Maisonettes and Standalone Flats

Individual flats (single residential units without common parts) are generally not covered by the FSO in isolation. However, if maisonettes or individual flats share escape routes, entrances, foyers, roofs, external walls, balconies or fire doors with other dwellings, then the building as a whole is likely within scope and requires a fire risk assessment. This is consistent with the way the FSO is interpreted for multi-occupied premises.

What Part of the Building Must Be Assessed?

When a fire risk assessment is required for a block of flats, the Responsible Person must consider all relevant fire safety risks, including:

• Common parts — corridors, stairwells, lobbies, service rooms, plant rooms
• Escape routes and protected means of escape
• Fire detection and alarm systems
• Emergency lighting
• Fire doors and compartmentation
• Structural elements, external walls, cladding and balconies (Fire Safety Act 2021)
• Flat entrance doors opening onto shared areas (Fire Safety Act 2021)

Not all risks will be the same in every building, and a fire risk assessment must be suitable and sufficient to reflect the actual use and layout of the premises.

Who Is Responsible for Carrying Out the Assessment?

The Responsible Person under the Regulatory Reform (Fire Safety) Order 2005 is legally obliged to ensure the fire risk assessment is carried out. This may be the:

• Building owner or freeholder
• Landlord
• Managing agent or facilities manager
• Residents’ management company or right-to-manage company

Even where the Responsible Person appoints a third-party fire risk assessor, legal responsibility remains with them. It is therefore essential to appoint a competent person to carry out the assessment.

When Must the Fire Risk Assessment Be Reviewed?

A fire risk assessment for a block of flats must be kept under review and updated:

• Regularly as part of fire safety management
• After significant changes to the building or its use
• Following incidents, alterations to escape routes, additions of external cladding or major refurbishment
• When new legal guidance or evidence affects risk evaluation

Keeping the fire risk assessment up to date is not merely good practice — it is a legal duty under the FSO.

Why Professional Fire Risk Assessments Matter

Although the law does not prescribe detailed timescales for when fire risk assessments must be repeated, the framework (including the Fire Safety Act 2021 and Fire Safety (England) Regulations 2022) gives Responsible Persons clear triggers for when assessments must be reviewed or updated.

For more complex buildings, especially those with greater risk (e.g., height, occupancy type, vulnerable residents), using an experienced professional assessor helps ensure that the assessment is robust, defensible and legally compliant.

Conclusion

A fire risk assessment is required by law for buildings that contain two or more flats with shared common parts, and it must be:

• Suitable and sufficient
• Carried out by a competent person
• Regularly reviewed and updated
• Inclusive of structure, external walls and flat entrance doors where applicable

If you are responsible for a building containing flats and are unsure whether your current fire risk assessment meets these legal requirements, contact Fire Risk Assessment Network for expert advice and compliant fire risk assessment services.

Frequently Asked Questions

Is a fire risk assessment required for every block of flats?

A fire risk assessment is required for buildings containing two or more flats with shared common parts, such as stairways, corridors, entrances, or lobbies. This includes most purpose-built blocks of flats and converted buildings. The assessment must cover the common parts and relevant fire safety features.

Do individual flats need a fire risk assessment?

Individual flats that are entirely self-contained do not usually require a separate fire risk assessment. However, flat entrance doors, external walls, and the building structure must be considered as part of the fire risk assessment for the building’s common parts under current legislation.

Who is responsible for arranging a fire risk assessment for flats?

The Responsible Person is legally responsible. This may be the building owner, freeholder, landlord, managing agent, or residents’ management company. Even if a fire risk assessor is appointed, legal responsibility remains with the Responsible Person.

What parts of a block of flats must be included in a fire risk assessment?

A fire risk assessment for flats typically includes:

• Common parts such as stairwells, corridors, and plant rooms
• Means of escape and fire safety measures
• Fire doors and compartmentation
• The building structure and external walls
• Flat entrance doors opening onto shared areas

The scope must be suitable and sufficient for the building and risks present.

How often should a fire risk assessment for flats be reviewed?

There is no fixed legal review period. A fire risk assessment must be kept under review and updated whenever it may no longer be valid. Reviews are commonly carried out annually and must also occur after significant changes, refurbishment, incidents, or new risks.

Does the height of the building affect fire risk assessment requirements?

Yes. Buildings over 11 metres in height have additional fire safety duties, including more frequent fire door checks and enhanced information-sharing requirements. These duties sit alongside, not instead of, the fire risk assessment requirement.

Can a managing agent or landlord rely on a checklist for flats?

A checklist may be used as a prompt, but it does not replace a suitable and sufficient fire risk assessment. For blocks of flats, particularly those with height, sleeping accommodation, or vulnerable occupants, a professional fire risk assessment is strongly advised.

What happens if a required fire risk assessment is not carried out?

Failure to carry out or maintain a suitable and sufficient fire risk assessment can result in enforcement action, including notices, prosecution, unlimited fines, and, in serious cases, imprisonment. Enforcing authorities assess both the assessment itself and how it was managed.

When should a professional fire risk assessor be used for flats?

A professional fire risk assessor is recommended where buildings involve:

• Multiple storeys or complex layouts
• Sleeping accommodation
• Vulnerable residents
• External wall systems or cladding
• Mixed-use or high-occupancy buildings

Professional assessments help ensure compliance and defensibility.