Fire risk assessment software for Higher-Risk Residential Buildings.

The BSA introduced multiple regimes that interact: a new occupied-buildings regime for HRBs, three regulatory Gateways covering design and construction of new HRBs, the Building Safety Regulator within HSE, the Principal Accountable Person role, the building safety case requirement, and significant amendments to the Fire Safety Order 2005 via Section 156.

For an existing high-rise residential building in operation, the practical effect is a step-change in audit grade. The PAP must register the building with the BSR, prepare and maintain a safety case report, comply with information and resident engagement duties, and respond to BSR direction. The FRA is one of the underlying documents the safety case rests on.

The "stay put" evacuation strategy on purpose-built blocks of flats has been the established design assumption since the 1960s. The strategy depends on adequate compartmentation: a fire in one flat is contained to that flat, while residents elsewhere remain safely in their homes. For buildings where compartmentation is verifiably intact, the strategy remains the operational approach. For buildings where compartmentation is in doubt (post-Grenfell external wall systems, partial cladding remediation, internal compartmentation gaps), an interim simultaneous evacuation strategy may be appropriate, often with a Waking Watch in place during the transitional period.

For the FRA on a high-rise residential building, the evaluation of the current evacuation strategy is one of the most important judgement calls. The assessor needs to consider what strategy the building was designed for, whether it remains appropriate given current conditions, what compensatory measures are in place if it does not, and what the action plan implications are. FRA Flow surfaces this section explicitly so it is not buried in generic narrative.

The post-Grenfell ban on combustible materials in external walls (Regulation 7(2) of the Building Regulations) applies to relevant residential buildings of 11m+ from 2022 onwards. For an FRA on an existing high-rise residential building constructed before that ban, the external wall system may not meet current standards. The FRA does not by itself require remediation; it records the position so the PAP can take advice.

In FRA Flow, the external wall observation is a structured field on the assessment, distinct from the general fire safety arrangements section. The assessor records what they could verify about the construction, what remained unverifiable, and any reference to a separate external wall investigation (PAS 9980 or similar). The PAP gets a clear position to feed into the safety case rather than a vague paragraph buried in the narrative.