An EWS1 form is a standard form that records whether a suitably qualified professional has assessed the external wall of a residential building for fire safety. Mortgage lenders and valuers use it to decide whether the external wall affects the value of a flat in the building. It was introduced in December 2019 by RICS, working with UK Finance and the Building Societies Association.
Why the form exists
After the Grenfell Tower fire in 2017, lenders became cautious about lending on flats in buildings with combustible cladding, and valuers had no consistent way of knowing what an external wall was made of. The EWS1 process, short for External Wall System, gave them one: a single form for the building, signed by a competent professional, that a valuer can rely on.
Demand for the forms quickly outstripped the number of professionals able to sign them, and many leaseholders found sales and remortgages delayed. Since then, government advice, RICS valuation guidance and lenders' own policies have all changed, and the range of buildings for which a lender needs an EWS1 form has narrowed. If you are asked for one, check with the lender or valuer whether it is actually needed for your building before commissioning one.
What the options mean
The signatory chooses one of two options, each with sub-options. Option A is for buildings where the external wall materials are unlikely to support combustion. Option B is for buildings where combustible materials are present in the external wall.
| Option | What it means |
|---|---|
| A1 | The external wall materials are unlikely to support combustion, and there are no attachments, such as balconies, with significant combustible materials |
| A2 | As A1, but there are attachments with combustible materials, and an appropriate risk assessment shows no remedial work is needed |
| A3 | As A1, but there are attachments with combustible materials where remedial work may be needed |
| B1 | Combustible materials are present, but the fire risk is low enough that no remedial work is needed |
| B2 | Combustible materials are present and an adequate standard of safety is not achieved, so remedial and possibly interim measures are needed |
An A1, A2 or B1 result generally means the external wall should not affect the valuation. An A3 or B2 result means work is needed, and the lender will take that into account. A B2 result is not a finding that the building is unsafe to live in, but it does mean the building needs remediation and, often, interim measures in the meantime.
Who can sign it
The form must be signed by a professional with the right expertise, who is a member of a relevant professional body.
- Option A can be signed by a professional with enough expertise to identify the materials in the external wall and any attachments, such as a chartered surveyor or other construction professional with the right experience.
- Option B needs a higher level of fire expertise, because it involves judging the risk from combustible materials. It is normally signed by a fire engineer or a professional with equivalent expertise in how external walls behave in a fire.
The signatory should hold professional indemnity insurance for the work. Ask any firm you are considering who will sign the form and what their qualifications are.
How long it lasts
An EWS1 form is valid for five years from the date it is signed, as long as nothing significant changes in the external wall during that time. It covers the whole building, not an individual flat, so once one has been completed, it can be used for every sale or remortgage in the building until it expires.
If the building is remediated after a B2 result, a new assessment and form will be needed to show the work has been done.
EWS1 and PAS 9980
PAS 9980:2022 is a code of practice from BSI for the fire risk appraisal of external wall construction in existing multi-storey, multi-occupied residential buildings. The appraisal it describes is usually called a FRAEW, short for fire risk appraisal of external walls.
The two serve different purposes:
- A FRAEW is a fire safety appraisal. It assesses the risk from the external wall and helps the Responsible Person decide what, if anything, needs to be done. It feeds into the building's fire risk assessment.
- An EWS1 form is a valuation tool. It gives a lender and valuer a simple, standard answer about the external wall.
An EWS1 signatory may base the form on a FRAEW, and many firms offer both together. Under the Fire Safety Act 2021, the external walls of buildings with two or more flats are covered by the Fire Safety Order, so the Responsible Person needs to consider them in the fire risk assessment whether or not anyone has asked for an EWS1 form.
Who arranges and pays for it
An EWS1 form covers the whole building, so it is normally commissioned by the building owner, freeholder, managing agent or residents' management company, not by an individual leaseholder. The assessor will need access to the outside of the building and, depending on what is found, may need to open up parts of the wall to see how it is built.
Whether the cost can be recovered from leaseholders through the service charge depends on the lease. If the form leads to remediation work, the Building Safety Act 2022 limits what qualifying leaseholders in buildings of at least 11 metres or five storeys can be charged for some costs. Take legal advice on your position, because the rules are detailed.
Typical prices depend on the height of the building, the number of elevations, whether intrusive inspection is needed, and whether construction drawings are available. Our external wall assessment page has guide prices.
How to get one
If a lender or buyer has asked for an EWS1 form:
- Check whether one already exists. Ask the freeholder or managing agent. A form signed within the last five years may still be valid.
- Check it is actually needed. Ask the lender or valuer to confirm that it is required for this building.
- Gather information. Construction drawings, specifications, operation and maintenance manuals, previous fire risk assessments and any earlier surveys of the external wall all help the assessor and can reduce the need for intrusive work.
- Appoint a competent professional. Check their qualifications, their professional body, their insurance and who will sign the form.
- Allow time for the result. Intrusive investigation, or a B2 result that needs further work, can take weeks or months.
If you are responsible for the building, the external wall is also part of your wider fire safety duties. Read do I need a fire risk assessment? and, for advice on a new or altered building, see our fire engineering and strategy service.
This guide is general information, not legal advice. Requirements depend on your building, and they differ in Scotland and Northern Ireland. Last updated 21 October 2026. Spotted something out of date? Tell us.