Housing fire risk assessments explained: BS 9792:2025 for flats and HMOs

The duty comes from the Fire Safety Order. It applies to the common parts of blocks of flats and houses in multiple occupation. And the Fire Safety Act 2021 made clear that it also covers the structure, the external walls, including cladding and balconies, and the front doors of individual flats.

Since 1 October 2023, the responsible person must record the whole assessment, in full, along with the name of anyone who helped make it. The flats themselves fall outside the Order.

BS 9792 is a code of practice published by BSI. It came into effect on 31 August 2025 and replaced PAS 79-2. It gives recommendations, not rules, so you can do things differently if the result is as good or better and you can justify it.

It also includes a model form for recording an assessment. Fire risk assessments in other buildings are covered by PAS 79-1, and specialist appraisals of external walls on blocks of flats by PAS 9980. This guide summarises the standard in our own words.

The standard applies to houses in multiple occupation, to blocks of flats and maisonettes, whether purpose-built or converted, to specialised housing, to student accommodation of those kinds, and to the parts of mixed-use buildings that lead to homes. It doesn't apply to a single household's own home, to short-term lets, to non-domestic buildings or to residential care homes. It applies to empty buildings too, but not while they're still under construction.

BS 9792 sets out nine steps. Gather information about the building and the people in it. Identify the fire hazards and how they're controlled.

Judge how likely a fire is. Look at the fire protection measures, and at how fire safety is managed. Judge how serious the consequences of a fire would be.

Then decide the level of risk, write an action plan, and set a date for review. Likelihood and consequences are judged separately, because one doesn't predict the other.

There are four types of assessment. A Type 1 looks at the common parts without opening anything up, and is enough for most buildings where there's evidence the construction is sound. A Type 2 adds intrusive sampling in the common parts, usually a one-off when serious defects are suspected.

A Type 3 adds a non-intrusive look inside a sample of the flats. A Type 4 adds intrusive sampling in the flats as well. It's the most thorough, and only for unusual cases, like a new landlord with no history of past works.

Even a Type 1 goes further than a walk round. It includes at least a sample of flat front doors, and the roof void if the roof is pitched. It also looks at the construction between the flats and the common parts, such as fire stopping in a sample of service risers, as far as can be seen without opening up.

It considers the external walls too. Traditional masonry walls without risky attachments are normally acceptable, but other wall types might need a specialist appraisal.

A fire risk assessment is not everything. It isn't a compliance audit, or an access audit for disabled people. It won't find hidden defects in construction, prove the fire resistance of the structure, or work out whether the building could collapse in a fire.

It isn't an external wall appraisal, a fire strategy, or a snagging check on new work. Knowing these limits helps you ask for the right work.

Who should carry it out? BS 9792 says a competent person. They don't need a particular academic qualification, but they should understand the law and the guidance, and how fire develops and how people behave.

They should understand the needs of residents who may need help to escape, older buildings built to earlier standards, and fire safety inside homes. The Building Safety Act includes a duty to appoint only competent assessors, but that part isn't in force yet. The government recommends checking competence now.

An assessment should be reviewed after material alterations or a change of use, and after a fire. It should also be reviewed after significant changes to what the assessment relied on or to the fire precautions, when a regulator asks, and at the interval the assessment sets. As a rough guide, the standard suggests a low-risk, low-rise block might have a review every two years and a new assessment every four, and higher-risk blocks a review every year and a new assessment every three.

These are not fixed rules.

Most fires in housing start inside residents' own homes. So BS 9792 asks the assessor to check whether there's a process for person-centred fire risk assessments, done with residents who might need help, and to flag it in the action plan if there isn't. In England, taller blocks now have a legal duty to offer these assessments, under the Residential PEEPs regulations that came into force on 6 April 2026.