What PAS 9980 is
PAS 9980:2022, Fire risk appraisal of external wall construction and cladding of existing blocks of flats, is a publicly available specification that sets out how to appraise the risk presented by an existing external wall. It was published to fill a specific and damaging gap: after Grenfell, thousands of buildings needed an assessment of their external walls, and there was no agreed method for doing it. The result was inconsistency, paralysis in the mortgage market, and remediation decisions driven by liability rather than by risk.
The output of a PAS 9980 appraisal is a fire risk appraisal of external walls, universally abbreviated to FRAEW. It is carried out by a competent person, usually a fire engineer, and it feeds the building's fire risk assessment rather than replacing it.
The most important thing about PAS 9980. It is not a compliance check. It does not ask whether the wall would satisfy today's Approved Document B if it were being built now; the answer for most existing buildings is no. It asks a different question: what is the risk to occupants from this wall, in this building, as it actually is? The answer is a rating and a proportionate recommendation.
What it applies to
- Existing blocks of flats, and buildings of similar use and risk profile.
- Multi-storey, multi-occupied residential buildings, typically 11 m and above, though the method can be applied lower where there is reason to.
- The external wall as a system: cladding, insulation, sheathing, membranes, cavity barriers, sub-structure, and the attachments and penetrations through it.
It does not apply to buildings under design or construction; those are governed by Approved Document B, BS 9991 and the combustible materials ban. It is not a substitute for the fire risk assessment under the Fire Safety Order, and it is not an EWS1 form.
How an appraisal is done
The method is a structured progression, and the discipline is in not skipping ahead.
- Desktop review. Drawings, specifications, O&M manuals, previous assessments, building control records, planning history. On most existing buildings this is where the first problem appears: the records do not describe what is actually there.
- Establishing the construction. Intrusive investigation: opening up the wall at representative locations to establish the actual build-up, the insulation type, the presence and condition of cavity barriers, and the quality of installation. This is the step that costs money and the step people try to avoid. An appraisal built on assumed construction is worth very little.
- Assessing fire spread potential. How the materials present would behave, how a fire could enter or spread within the cavity, and what the geometry of the façade does to a plume. Re-entrant corners, balconies, and vertical channels all matter more than an area-weighted material summary suggests.
- Assessing the consequences. This is what makes PAS 9980 an engineering method rather than a materials audit. Height, occupancy profile, the evacuation strategy, the number of stairs, compartmentation condition, detection and alarm provision, sprinklers, and fire service access all change the consequence of the same façade defect.
- Risk rating and recommendation. A rating, then proportionate recommendations: no action, management measures, interim measures, partial remediation, or full remediation.
The risk ratings
There are three: low, medium and high. Not four: there is no separate "tolerable" rating, though the word "tolerable" appears throughout the PAS as the test applied when deciding between them.
| Rating | What it means in practice |
|---|---|
| Low | The wall does not present a significant risk of external fire spread. No remedial work to the wall is needed on fire safety grounds. Ordinary management and the existing fire risk assessment continue. |
| Medium | There is an element of uncertainty about the risk, which can either be tolerated or needs further refinement before the conclusion is reached, but there must be sufficient certainty that the risk is not high. Interim or mitigating measures and a revisited fire risk assessment are common outcomes. |
| High | The risk is not tolerable. Immediate interim measures (commonly a waking watch pending an alarm installation, and often suspension of the stay-put strategy), with remediation required. |
You cannot score your way to a rating. Clause 13 says so directly: "It is not intended that this be seen as an attempt to introduce quantification (i.e. that if the number of positive risk factors outweigh the number of negative factors the result is, therefore, 'low' risk). Rather, a larger number simply demonstrates a stronger evidence base when drawing a conclusion. Equally, it follows that a single risk factor, be it positive or negative, might, if of such magnitude and significance, outweigh any number of opposite risk factors." Treat any tool, spreadsheet or template that adds up weightings and returns a rating with suspicion; it is doing the one thing the PAS tells you not to do.
Note also that the lettered categories people reach for (A1, A2, A3, B1, B2) are not PAS 9980 ratings. They belong to the EWS1 form, and A1/A2 also collide confusingly with the European reaction-to-fire classes. Keep the three vocabularies separate.
Two buildings with identical façades can legitimately land on different ratings. That is the method working as intended, not an inconsistency: a sprinklered building with two stairs, a simultaneous evacuation alarm and intact compartmentation carries a materially lower consequence than a single-stair block relying on stay-put with no detection in the common parts.
PAS 9980 and EWS1
These are constantly confused, and they are not the same thing.
| PAS 9980 / FRAEW | EWS1 | |
|---|---|---|
| What it is | An engineering appraisal of risk, with a report behind it | A one-page form recording the outcome of an assessment |
| Purpose | Fire safety: informs the fire risk assessment and remediation decisions | Valuation: tells a lender whether the wall is a valuation risk |
| Who it is for | The responsible person, the accountable person, the building owner | Lenders and valuers |
| Status | Recognised code of practice | An industry form, not a statutory requirement, and not a safety certificate |
An EWS1 form is often produced off the back of a FRAEW. A FRAEW is never produced off the back of an EWS1. And an EWS1 rating of B2 does not by itself tell you what the risk is or what to do about it; that is what the appraisal is for.
Competence and the limits of the method
PAS 9980 puts real weight on the assessor's judgement, which means the assessor's competence is the load-bearing element. The specification expects a competent fire engineer with knowledge of façade construction, fire dynamics and the relevant test evidence, and it expects the report to state what was and was not investigated.
The three things that most often make an appraisal unusable are: no intrusive investigation, so the construction is assumed; the consequence analysis reduced to a checklist rather than reasoned for this building; and recommendations that do not follow from the rating. All three are visible from the contents page.
Last reviewed 25 July 2026 against the editions named above. Standards are revised; check the current published edition before relying on anything here in a design.