EWS1 forms
An EWS1 form, External Wall System form, is a standardised document, developed in 2019 by RICS, UK Finance, and the Building Societies Association in the wake of the Grenfell Tower fire, that records the findings of a fire safety assessment of the external walls of a residential building. Its purpose is to give mortgage lenders and valuers confidence about the fire risk profile of a building's external wall system, including cladding, insulation, fire breaks, and balconies, before they will proceed with a sale, purchase, or remortgage of a flat within it.
An EWS1 form is not a statutory requirement, a general building safety certificate, or a substitute for a fire risk assessment. It is a lending and valuation instrument. The fact that a building holds an EWS1 form, or does not require one, says nothing about its overall fire safety or structural condition. A building can have serious fire safety deficiencies without having triggered an EWS1 requirement, and a building can need an EWS1 solely because of lender practice rather than any identified risk.
When is an EWS1 required?
Whether a lender or valuer will require an EWS1 depends on the building's height and the nature of its external wall construction. As of 2026, the position under RICS guidance is:
Buildings over 18 metres are generally subject to EWS1 requirements where the building has cladding, combustible insulation, or stacked combustible balconies. This threshold reflects the height at which fire service ladders typically cannot reach.
Buildings between 11 and 18 metres require an EWS1 only where specific risk factors are present, for example, a significant amount of cladding covering approximately a quarter or more of the elevation, or balconies constructed from combustible materials that stack vertically.
Buildings under 11 metres are generally not required to have an EWS1 following government guidance issued in 2022. Most major lenders have accepted this position, though individual lender policies continue to vary and some still request an EWS1 regardless of height.
Buildings without any cladding, regardless of height, are generally not required to have an EWS1.
An EWS1 form is valid for five years from the date of assessment. After that period, a new assessment may be required if material changes have been made to the external wall or attachments. In April 2025, UK Finance, RICS, and the BSA updated their joint guidance to clarify that older forms, including those over five years old, may remain acceptable in some circumstances, and that lenders should apply a more flexible, evidence-based approach rather than automatically requiring a new assessment.
What the ratings mean
After the fire safety assessment, the building receives one of five ratings across two option categories:
Option A - external wall materials are unlikely to support combustion:
A1 - no cladding contains significant quantities of combustible material; no attachments such as balconies include combustible materials. No remediation needed. Lenders generally accept this rating.
A2 - cladding or attachments are present, a risk assessment has been completed, and no remediation works are required. No remediation needed. Lenders generally accept this rating.
A3 - cladding meets the limited combustibility standard but attachments to the external wall (typically balconies) may require remedial works. Some remediation may be needed. Valuers may assign a nil value for lending purposes.
Option B - combustible materials are present in the external wall:
B1 - combustible materials are present but a fire engineer has concluded that the fire risk is sufficiently low that no remedial works are required. Lenders generally accept this rating.
B2 - combustible materials are present and a fire engineer has concluded that the fire risk is high enough to necessitate remediation. Lenders typically will not lend on a B2 property until a costed, funded, and timed remediation programme is in place.
Who commissions an EWS1 and what it means for buy-to-let landlords
An EWS1 can only be commissioned by the building owner, the freeholder, a residents' management company, or a right-to-manage company, not by an individual leaseholder or flat owner. The assessment is typically arranged through the managing agent and relates to the whole building rather than any individual flat. A leaseholder who is a buy-to-let landlord has no right to demand that the freeholder obtain an EWS1, though they can apply pressure through the managing agent and through the Building Safety Act 2022 remediation order regime.
From a buy-to-let landlord's perspective, EWS1 status affects several things simultaneously: the ability to remortgage the property, the ability to sell it to someone requiring a mortgage, buildings insurance costs, planned remediation timelines, and service charge levels where remediation costs are passed through to leaseholders. EWS1 issues frequently surface through rising service charges for remediation works, for an explanation of how service charges work and what leaseholders can and cannot be required to pay post the Building Safety Act 2022, see the August definition of the service charge.
The Building Safety Act 2022 introduced protections limiting leaseholder liability for certain remediation costs, particularly where the freeholder or developer is responsible for the defects. These protections do not make the EWS1 process redundant, lenders still require the form for affected buildings, but they change the financial position of leaseholders in buildings requiring remediation.
August's document management feature stores EWS1 forms, fire risk assessments, and building safety documentation alongside the rest of a landlord's compliance records, so nothing is missing when a lender, insurer, or agent asks for evidence.
In our experience supporting buy-to-let landlords with leasehold flats, EWS1 is one of those issues that tends to emerge at the point of remortgage or sale rather than during an ongoing tenancy, which is precisely when the time pressure is highest. Keeping a copy of the building's current EWS1 form, if one exists, and monitoring the managing agent's communications about any planned remediation is the most practical thing a landlord in a potentially affected block can do in advance of needing it.
Frequently asked questions
What is an EWS1 form?
An EWS1 (External Wall System) form is a document produced by a qualified fire safety professional that records the findings of an assessment of a residential building's external walls, including cladding, insulation, balconies, and fire breaks. It was developed in 2019 by RICS, UK Finance, and the Building Societies Association to help mortgage lenders and valuers assess fire risk for the purpose of lending on flats in multi-occupancy buildings. It is not a legal requirement, a general safety certificate, or a substitute for a fire risk assessment.
When is an EWS1 form required?
Under current RICS guidance, EWS1 forms are generally required for buildings over 18 metres with cladding or combustible materials, and for buildings between 11 and 18 metres where specific risk factors, such as significant cladding coverage or stacked combustible balconies, are present. Buildings under 11 metres are generally not required to have one following government guidance issued in 2022, though individual lender practice varies. An EWS1 is not required for buildings without cladding, regardless of height.
What does a B2 EWS1 rating mean?
A B2 rating means that a qualified fire engineer has found combustible materials in the external wall and concluded that the fire risk is high enough to require remediation works before the building meets an acceptable safety standard. Most mainstream mortgage lenders will not lend on a property with a B2 rating until a costed, funded, and timed remediation programme is in place. Until remediation is confirmed, properties with a B2 rating may be valued at nil for lending purposes, meaning they can typically only be sold for cash.
How long is an EWS1 form valid?
An EWS1 form is valid for five years from the date of assessment. However, following updated guidance from UK Finance, RICS, and the BSA in April 2025, lenders are encouraged to apply a more flexible approach, meaning older forms may remain acceptable in some circumstances rather than automatically requiring a new assessment when the five-year period expires. A new assessment may still be needed if material changes have been made to the external wall.
Who pays for an EWS1 assessment?
The building owner, the freeholder, or a residents' management company where leaseholders have exercised their right to manage, commissions and pays for the EWS1 assessment. Individual leaseholders and flat owners cannot request one themselves, though they can put pressure on the freeholder or managing agent. Assessment costs vary widely by building size and complexity, typically ranging from a few thousand pounds for a small block to £25,000 or more for a large high-rise requiring intrusive inspection.
