What Is PAS 9980 and Why Was It Introduced?

PAS 9980: The Standard for External Wall Fire Risk Appraisal

PAS 9980:2022 is the British Standard published by BSI that sets out the methodology for assessing the fire risk associated with the external walls and cladding systems of existing residential buildings. It was developed in response to the Grenfell Tower fire and the subsequent focus on external wall fire safety in the UK's residential building stock.

PAS 9980 does not set a pass or fail threshold. It provides a structured framework for a chartered fire engineer to appraise the risk presented by an external wall system and to form a professional judgement about the risk level — from negligible to very high — and whether that risk is tolerable or requires remediation.

Why Was PAS 9980 Introduced?

Following the Grenfell Tower fire in June 2017, it became clear that there was no established methodology in the UK for assessing the fire risk associated with existing external wall systems. The EWS1 process — introduced in 2019 to help mortgage lenders assess residential blocks — created demand for external wall assessments but without a defined methodology for carrying them out.

Early EWS1 assessments varied significantly in approach and quality. Some were carried out by unqualified assessors. Others were overly conservative, requiring remediation of materials that posed no realistic fire risk. PAS 9980 was developed to establish a consistent, risk-proportionate methodology that could be applied by competent fire engineers.

What Does a PAS 9980 Assessment Involve?

A PAS 9980 Fire Risk Appraisal of External Walls (FRAEW) involves the following stages:

• Desktop review — review of available information including original design drawings, building control records, previous surveys and any existing cladding information
• Site inspection — a physical inspection of the external wall, including intrusive investigation where necessary to identify materials and construction details
• Material identification — identification of cladding materials, insulation, cavity barriers, fire stops and fixings, with reference to test data and reaction to fire classifications where available
• Risk appraisal — application of the PAS 9980 risk appraisal methodology to assess the likelihood and consequence of external fire spread, taking into account building height, occupancy, internal fire precautions and the characteristics of the external wall system
• Risk rating — assignment of a risk rating from 1 (negligible) to 4 (very high) for each elevation and the building overall
• Recommendations — where risk is assessed as intolerable, recommendations for interim measures and/or remediation

What Is the Relationship Between PAS 9980 and EWS1?

An EWS1 form is the document issued to mortgage lenders to confirm the outcome of an external wall assessment. A PAS 9980 FRAEW is the technical assessment that underpins an EWS1 form. The FRAEW is the engineering work; the EWS1 form is the output document that lenders and valuers rely on.

Not all buildings require an EWS1 form. RICS guidance limits the circumstances in which lenders should request one. But where an EWS1 is required, the underlying assessment should be a PAS 9980 FRAEW carried out by a competent fire engineer.

Who Needs a PAS 9980 Assessment?

PAS 9980 applies to existing residential buildings — typically blocks of flats — where there is a question about the fire risk associated with the external wall. The most common triggers are:

• A leaseholder attempting to sell or remortgage a flat has been asked by their lender for an EWS1 form
• A managing agent or freeholder is seeking to understand the external wall fire safety position of their building
• The building is being registered with the Building Safety Regulator and external wall fire risk is part of the building safety case
• The building is undergoing major refurbishment that includes changes to the external wall