BS 9792:2025 Fire Risk Assessment Types Explained: Which Does Your HMO Need?

Submit your HMO licence application with the wrong type of fire risk assessment and the council can simply reject it. You'll have wasted the assessor's fee, delayed your application by weeks, and still need to commission the right one. The problem is that most landlords don't know there are four different types of fire risk assessment under BS 9792:2025, let alone which one applies to their property.

This guide explains each type clearly, tells you which one your HMO is likely to need, and shows you where online self-assessment ends and where an in-person assessor must take over.

What is BS 9792:2025?

BS 9792:2025 is the British Standard that defines how fire risk assessments must be conducted in residential premises. Published by the British Standards Institution in August 2025, it replaced PAS 79-2:2020, which was withdrawn. For HMO landlords, it is now the definitive framework your assessor should be working to.

The standard applies to HMOs, blocks of flats, student accommodation, and specialised housing. It does not apply to private single-household dwellings or short-term lets. If you want to understand what changed from the previous guidance, our breakdown of BS 9792:2025 changes for HMO landlords covers that in full.

The Four Assessment Types

BS 9792:2025 establishes four distinct assessment types. They are not interchangeable. Each one has a different scope and a different level of physical intrusion into the building. Choosing the wrong type is not a technicality: it can mean your assessment is deemed unsuitable and insufficient, which is the legal test under the Regulatory Reform (Fire Safety) Order 2005.

Type 1: Common Parts Only (Non-Intrusive)

This is the most common assessment type for HMOs. The assessor inspects the shared areas of the building: entrance halls, corridors, stairwells, communal kitchens, and fire escape routes. The inspection is visual and non-intrusive, meaning nothing is opened up or dismantled.

A Type 1 assessment covers fire doors in the common parts, emergency lighting, fire alarm coverage, means of escape, fire extinguishers, and evidence of fire hazards in shared spaces. It does not go inside individual bedsits or flats, and it does not open up walls or ceilings to inspect concealed fire stopping.

This is what most standard HMOs need. It is also the level that a competent, responsible person can carry out themselves, using a structured methodology like the one set out in our HMO self-assessment guide.

Type 2: Common Parts with Intrusion

A Type 2 assessment covers the same ground as a Type 1, but the assessor also opens up parts of the building structure to inspect elements that cannot be seen visually: cavity barriers, fire stopping around services (pipes, cables, ducts), and the condition of concealed voids.

This type is used when the construction history of the building raises doubt about hidden fire protection. Older properties, particularly pre-1920 timber-framed conversions, often have voids and gaps that were never sealed to modern standards. If a Type 1 assessor spots signs of inadequate compartmentation but cannot confirm without opening up the structure, a Type 2 is the next step.

Type 2 always requires an experienced, professionally qualified fire risk assessor. It is not a self-assessment exercise.

Type 3: Common Parts and Dwellings (Non-Intrusive)

A Type 3 assessment extends the scope into the individual dwellings, inspecting a sample of flats or bedsits as well as the common parts. The inspection inside each unit remains visual: it looks at flat-front fire doors, internal layout, storage of combustibles, and cooking arrangements.

This type is relevant when there is concern that fire risks within individual units could affect other occupants. It is also used when the flat-front fire doors cannot be adequately assessed from the common side alone, or when a council licensing inspection has raised questions about fire spread between units. Landlords with non-compliant flat-front fire doors are more likely to face a request for this level of assessment.

Type 4: Common Parts and Dwellings (with Intrusion)

Type 4 is the most thorough assessment available. It combines the scope of a Type 3 (inspecting inside dwellings) with the intrusion of a Type 2 (opening up structure). This is reserved for high-risk or complex buildings: typically large purpose-built blocks of flats, higher-risk buildings under the Building Safety Act 2022 (18 metres or above), or properties where a previous assessment identified serious compartmentation failures.

Most HMO landlords will never need a Type 4. If you do, the licensing authority or building safety regulator will tell you.

Which Type Does Your HMO Need?

The honest answer is that most HMOs need a Type 1. But the decision depends on several factors, and getting it wrong in either direction creates problems: under-assessing leaves you legally exposed, while over-assessing costs unnecessary money.

Start with Type 1 if:

• Your HMO is a converted terraced or semi-detached house, typically 2 to 4 storeys
• The building was constructed or comprehensively refurbished after 1980
• You have no outstanding concerns about compartmentation or fire stopping
• Your licensing authority has not requested a higher-level assessment

Move to Type 2 if:

• The property is pre-1920 or timber-framed
• A previous Type 1 identified potential compartmentation weaknesses that could not be confirmed visually
• The council or a fire safety officer has specifically requested intrusive inspection
• The building has had unexplained alterations or conversions where fire stopping quality is unknown

Consider Type 3 if:

• Individual flat-front fire doors cannot be adequately assessed from the common side
• There are high-risk occupants with mobility or cognitive impairments requiring a Personal Emergency Evacuation Plan
• The council has raised concerns about fire risks within individual units following a previous inspection

Type 4 is for complex or higher-risk buildings where intrusive inspection of the structure or inspection inside dwellings (or both) has been formally requested. For most landlords managing a standard HMO, this will not apply.

What FRASafe Covers

FRASafe's online assessment is structured to meet the requirements of a Type 1 fire risk assessment under BS 9792:2025. It works through five modules aligned to the standard's methodology: building profile, ignition and fuel sources, means of escape and fire detection, safety management, and risk evaluation.

The scope is broader than just corridors and stairwells. FRASafe checks the fire alarm system grade across the whole property (from Grade A commercial systems down to single battery alarms), verifies that smoke alarms are present on every storey with living accommodation, and confirms CO alarms in every room containing a fixed combustion appliance. It also checks that bedroom doors have thumb-turn locks so occupants can escape without a key: a means-of-escape requirement that applies to every habitable room.

What it does not do is inspect inside individual dwellings room by room, or open up walls and ceilings to check concealed fire stopping. That keeps it firmly within Type 1 scope.

When you complete it, you get a council-ready PDF that documents your findings, identifies action points, and records the assessment in the format required by the RRO 2005. FRASafe guides you through a BS 9792:2025-aligned assessment, free to complete, £45 for the council-ready PDF. Start your Type 1 HMO fire risk assessment here.

If your property needs a Type 2, 3, or 4 assessment, that requires a qualified in-person assessor with access to the building. FRASafe can connect you with one: book an in-person fire risk assessor.

A Note on Competence

Whichever type you need, BS 9792:2025 is clear that the assessment must be carried out by a competent person. For a Type 1 self-assessment, that means the responsible person (usually the landlord) must have sufficient knowledge of fire safety in HMOs to conduct a meaningful inspection and evaluate risks accurately. FRASafe's question framework is designed to guide you through this systematically.

For Types 2 to 4, "competent" means a professionally trained fire risk assessor. The standard raises the bar: assessors should ideally hold registration with a third-party certification body such as the IFPO or IFE.

Next Steps

For most HMO landlords, the path is straightforward: carry out a Type 1 assessment of your common parts, document it properly, and review it annually or after any significant change. If your property's age, construction, or complexity puts it into Type 2, 3, or 4 territory, commission a qualified assessor before your next licence renewal.

Start your Type 1 assessment at FRASafe's HMO assessment tool, or if you already know you need an in-person assessor, book one here.