The EWS1 form (External Wall System Fire Review) was introduced in December 2019 by RICS, UK Finance and the Building Societies Association. Its purpose is to provide a consistent way for valuers and lenders to understand the fire risk associated with a building’s external wall system when assessing flats for sale or remortgage.
It is important to be clear from the outset:
EWS1 is not a legal requirement. It is a lender and valuer tool, used in specific circumstances to support mortgage decisions.
When is an EWS1 required?
There is no single rule that determines whether an EWS1 will be requested.
Height is a factor, but it is not the only one. While early guidance focused on buildings over 18 metres, in practice EWS1 forms may be requested for buildings below 18 metres where there are visible or suspected fire risk factors within the external wall system.
Typical triggers include:
- Presence of combustible materials in the external wall build-up
- Uncertainty over cladding, insulation or balconies
- Valuer or lender policy where sufficient fire safety assurance is not otherwise available
Some transactions proceed without an EWS1. Others stall because one is requested. This reflects lender risk appetite rather than a statutory threshold.
What does the EWS1 assess?
An EWS1 considers the external wall system as a whole, which may include:
- Cladding and insulation
- Cavity barriers and fire stopping
- Balconies, decking and attachments
- Fixings and interfaces
The form provides one of a small number of outcomes, indicating whether the external wall system presents a level of fire risk that may affect valuation or lending.
EWS1 and PAS 9980: how they relate
PAS 9980:2022 is a publicly available specification that sets out a methodology for conducting a Fire Risk Appraisal of External Walls (FRAEW) on existing blocks of flats.
Key points:
- PAS 9980 does not replace the EWS1.
- PAS 9980 provides a structured, risk-based approach for competent professionals to assess external wall fire risk.
- A FRAEW carried out in accordance with PAS 9980 may inform the evidence used by a valuer or fire engineer when an EWS1 is requested.
The two are related, but not interchangeable. A PAS 9980 appraisal does not automatically produce an EWS1 outcome.
Validity of an EWS1
An EWS1 form is generally considered valid for up to five years, provided:
- There have been no material changes to the external wall system
- No new information has come to light that would alter the fire risk assessment
If changes occur, a new assessment may be required.
Risk reduction and remediation
External wall fire risk is assessed holistically. There is no single material change that guarantees a different EWS1 outcome.
In some cases, professionals may identify risk reduction measures such as:
- Replacement of combustible components
- Improvements to cavity barriers or fire stopping
- Removal or alteration of attachments that contribute to fire spread risk
Any such measures must be considered case by case, based on the overall wall construction, building use, and evacuation strategy. Decisions should always be made by suitably qualified and competent professionals.
Risk reduction and remediation
External wall fire risk is assessed holistically. There is no single material change that guarantees a different EWS1 outcome.
In some cases, professionals may identify risk reduction measures such as:
- Replacement of combustible components
- Improvements to cavity barriers or fire stopping
- Removal or alteration of attachments that contribute to fire spread risk
Any such measures must be considered case by case, based on the overall wall construction, building use, and evacuation strategy. Decisions should always be made by suitably qualified and competent professionals.
Key takeaways
- EWS1 is a lender and valuer tool, not a statutory requirement
- Height alone does not determine whether an EWS1 is requested
- PAS 9980 provides a framework for external wall fire risk appraisal, not a guaranteed route to a particular outcome
- External wall fire risk must be assessed holistically, not optimised through isolated material changes