Written by the Brady Solicitors Litigation Team. Brady Solicitors advises leaseholders, managing agents, freeholders and RTM companies on service charge disputes, lease extensions and Building Safety Act compliance.
If you are trying to sell or remortgage a flat and you have been told an EWS1 form is needed, you are not alone. Hundreds of thousands of leaseholders in multi-storey residential buildings have found their transactions stalled by concerns about external wall construction. This article explains what an EWS1 form is, what the five possible ratings mean in practice, when lenders can legitimately require one, and what changed in December 2022. That change created a parallel route to mortgage lending for leaseholders in many cladding-affected buildings, and it is one that not every solicitor or lender is applying consistently. We also cover how EWS1 sits alongside the Building Safety Act 2022, and what your options are if a sale or remortgage has stalled.
What is an EWS1 Form?
EWS1 stands for External Wall System 1. It is not a statutory form created by Parliament or a government agency. It’s a standardised assessment process developed jointly by the Royal Institution of Chartered Surveyors (RICS), UK Finance, and the Building Societies Association in December 2019, in direct response to the mortgage market freezing up for flat owners in multi-storey blocks following Grenfell.
After Grenfell, lenders were rightly concerned about fire safety in residential buildings with external cladding systems. But without a standardised way to assess risk, many simply refused mortgages on any flat above a certain height, whether the building had problematic cladding or not. The EWS1 process was designed to cut through that blanket approach: a qualified assessor inspects the building’s external wall construction, identifies the materials present, and issues a rated certificate. The lender can then make an informed decision rather than defaulting to a flat refusal.
The form covers the external wall system as a whole: not just the visible cladding panels, but the insulation, the cavity barriers, the fire stopping, and the substrate behind them. A building can look fine from the street and still have significant fire risk in its wall construction.
The EWS1 Rating System: What A1 to B2 Means
The EWS1 form (RICS 3rd edition, 2022) divides buildings into two options depending on the materials in the external wall itself. Understanding the distinction matters, because the A and B ratings are not measuring the same thing.
Option A: Primary wall material are of limited combustibility
Option A applies where the primary materials in the external wall are of limited combustibility. The ratings within Option A turn on the assessor’s view of attachments to the building, including elements such as balconies, rather than the wall construction itself:
| A1 | No attachments contain significant quantities of combustible materials. The external wall and its attachments are considered to present no significant fire risk. |
| A2 | Attachments are present and have been risk-assessed. The assessment confirms that no remedial works to the attachments are required. |
| A3 | Neither A1 nor A2 apply. There may be potential costs of remedial works to attachments. |
Option B: Combistible materials are present in the external wall
Option B applies where combustible materials are present in the wall construction itself — not just in attachments. This is the more serious category:
| B1 | Combustible materials are present in the external wall, but the assessor considers the fire risk to be sufficiently low that no remedial works are required. |
| B2 | Combustible materials are present in the external wall and the assessor considers the fire risk is sufficiently high that remedial works are required. |
In practice, A1, A2, and B1 generally allow mortgage transactions to proceed. A3 and B2 are the ratings that stall sales and remortgages. They are different in nature: A3 concerns attachments on an otherwise low-risk wall; B2 concerns the wall system itself but valuers commonly treat both as meaning lending is not appropriate until the relevant works are complete. If you have an A3 or B2 on your building, the practical effect on your transaction is likely to be the same even though the underlying issue is not.
EWS1 forms are generally valid for 5 years from the date of assessment, provided there has been no material change to the building’s external wall system in the interim. If remediation works have been carried out since the original assessment, the form will need updating.
When is an EWS1 form actually required?
This is where leaseholders consistently run into confusion. The short answer is: not as often as lenders have been requesting them. The longer answer requires understanding how the guidance has shifted.
When EWS1 was first introduced, some lenders applied it broadly to any multi-storey block over 4 storeys, regardless of whether the building had any external cladding at all. RICS and the government have progressively pushed back on this. Under the current RICS guidance framework, supported by the government and by a joint statement from UK Finance, the Building Societies Association, and RICS issued in December 2022:
Buildings with no cladding should not normally require an EWS1 form. If a building has standard brick, stone, or render external walls with no combustible cladding or insulation system, an EWS1 assessment is not appropriate.
Buildings under 18 metres with no known external wall concerns should not normally require an EWS1 form. RICS guidance and the government’s position is that blanket requirements for these buildings are disproportionate.
Buildings over 18 metres with combustible cladding or insulation are where the form is most likely to be needed. The assessor’s professional judgement is required to determine whether an assessment is appropriate.
The problem in practice is that lenders do not always follow this guidance. A lender is entitled to require additional information as a condition of lending, and some continue to request EWS1 forms outside the parameters the guidance sets. If your lender is requiring an EWS1 form for a building that the guidance says should not need one, your solicitor can raise this directly with the lender. In some cases, a letter from a surveyor confirming the building construction is sufficient to satisfy the lender’s requirements without a full EWS1 assessment.
Who has to commission and pay for an EWS1 form?
This is one of the most contentious aspects of EWS1 in practice. The form has to be carried out by a qualified professional: either a fire engineer or a chartered building surveyor holding qualifications recognised under RICS guidance, and operating in accordance with PAS 9980:2022, the BSI Publicly Available Specification for fire risk appraisal of external wall construction and cladding of existing blocks of flats.
The assessment is of the building as a whole, not the individual flat. That means the freeholder or their managing agent has to commission it. A leaseholder can’t commission an EWS1 form themselves. This creates an immediate problem: if the freeholder refuses to commission an assessment, or is slow to do so, the leaseholder can’t sell or remortgage, and has no direct way to force the process.
As for cost, the position is not simple. The assessment itself is typically paid for by the freeholder and then potentially sought through the service charge. Here the Building Safety Act 2022 becomes relevant. Schedule 8 of the BSA caps what qualifying leaseholders can be charged through the service charge for building safety works. Whether an EWS1 assessment cost falls within the scope of Schedule 8 depends on the specific circumstances and the nature of the building’s defects. This is an area where specialist legal advice is worth getting before accepting a service charge demand that includes assessment costs.
What changed in December 2022
The most significant development since the form’s introduction is the joint industry statement agreed on 20 December 2022 by UK Finance, the Building Societies Association, and RICS, committing the major mortgage lenders to a risk-based approach that no longer treats EWS1 as the only route to lending on a flat in a cladding-affected building.
Under the December 2022 commitment, lenders agreed to consider proceeding with mortgage lending without an EWS1 form where there is sufficient evidence that the building’s fire safety issues are being addressed. The three routes that can support this are:
Developer self-remediation. Where the developer has committed to fund and carry out the remediation works, evidence of that commitment can support lending without EWS1.
A recognised government scheme. Where the building is within scope of a government remediation fund, lenders can proceed on the basis that the remediation path is assured.
BSA leaseholder protections, evidenced by a Leaseholder Deed of Certificate. Where a qualifying leaseholder can demonstrate they are protected from remediation costs under the Building Safety Act 2022, a completed Leaseholder Deed of Certificate can support a lending decision.
The major lenders signed up to this framework in December 2022, with further lenders joining through 2023. RICS updated its valuation guidance to reflect the same risk-based approach, reducing the expectation that EWS1 forms would be required as a matter of course.
In practice, the results have been mixed. Independent monitoring found that as late as October to December 2023, lenders were still requesting an EWS1 form for around 9% of flat mortgage valuations, the same proportion as in April to June 2021, before the pledge was agreed. The direction of travel is toward less reliance on EWS1, but the form has not gone away. In buildings where the December 2022 routes cannot be evidenced, lenders typically still expect to see one.
You have been told the building has a B2 rating. What now?
A B2 rating tells you that an independent assessor has concluded that combustible materials are present in the building’s external wall and that remedial works are required. Before December 2022, this almost always meant your transaction stalled until those works were done. The position is more nuanced now.
The first question to ask is whether your building falls into one of the December 2022 categories: is there a developer commitment to fund the works, is the building within a government remediation scheme, or do you have a Leaseholder Deed of Certificate that evidences BSA protection? If any of those routes are available, your solicitor should be raising them with the lender directly rather than simply waiting for remediation to complete. Some lenders will proceed on this basis; others remain cautious in practice.
If none of those routes apply, the practical position remains difficult. For a sale, you’re likely looking at a restricted buyer pool or a price reduction until the building’s rating improves. For a remortgage, you may be constrained to your existing lender’s available products. Neither is a straightforward situation and the options depend on the specific building, its height, and the remediation picture.
On the cost of remediation itself: if the building is 11 metres or more (or 5 or more storeys), Part 5 of the Building Safety Act 2022 may protect you from paying for remediation of cladding defects entirely, and limits what you can be charged for non-cladding defects. The BSA protections concern who pays for the works. They do not directly resolve the mortgage lending position while those works are outstanding, but they can determine whether you are financially exposed to a bill in the meantime.
EWS1 and the Building Safety Act: Two parallel systems
The Building Safety Act 2022 did not replace EWS1, and the two operate as separate frameworks addressing overlapping but distinct concerns.
The BSA created formal statutory mechanisms for building safety oversight, leaseholder protections, and remediation. Its remediation framework asks: who is responsible for making the building safe, and who bears the cost? The qualifying leaseholder protections under Schedule 8 cap leaseholder liability for cladding and non-cladding defects in buildings above the relevant height threshold.
EWS1, by contrast, is a mortgage market mechanism. It asks: should a lender be prepared to lend on this building given the state of the external wall? It has no statutory basis. RICS, UK Finance, and the Building Societies Association produced it and maintain it. A B2 outcome does not create legal liability under the BSA, but it will often reflect the same underlying defect that the BSA’s remediation framework is designed to address.
In practice, the two systems interact at service charge level. The cost of an EWS1 assessment, and the cost of any remediation identified by it, will typically be sought from leaseholders through the service charge unless the BSA’s leaseholder protections apply. Landlord certificates under the BSA, which freeholders must provide to confirm the costs they are and are not seeking to recover, may also contain information that affects how the building’s fire safety status is presented to lenders.
One more distinction matters: the BSA’s ‘relevant defect’ regime applies to buildings of 11 metres or more. EWS1 applies wherever the lender considers an assessment necessary. A building below 11 metres isn ot within scope of the BSA’s remediation framework, but a lender could still require an EWS1 form if the external wall raised concerns.
What to do if your sale or remortgage has stalled because of EWS1
If your transaction has been held up waiting for an EWS1 form, or if you have received a B2 or A3 rating and do not know where you stand, the starting point is to understand exactly what the block is. There are a few common scenarios:
The freeholder has not commissioned an assessment. Your first step is to write formally to the freeholder or managing agent requesting that an EWS1 assessment be commissioned and given a timetable. Keep a record of this correspondence. If the freeholder continues to obstruct or delay, it becomes relevant to any subsequent legal action.
Your lender is requiring EWS1 for a building that does not have cladding. This is a common situation. Your solicitor can write to the lender citing the current RICS guidance and requesting that they review their requirement. A surveyor’s letter confirming the external wall construction may be sufficient.
The building has a B2 rating and remediation has not started. Check whether you are a qualifying leaseholder in a relevant building under the BSA: this determines whether you can be required to contribute to the remediation costs. If the freeholder is seeking to recover costs from you that Schedule 8 does not permit, you can challenge this at the First-tier Tribunal.
Youa re stuck on a mortgage product and can’t remortgage. This is currently one of the most difficult situations in the EWS1 space. There is no straightforward legal route to force a lender to lend. The practical path is typically to push hard on remediation (either through the BSA’s remediation framework or by engaging with the government’s building safety programmes) so that the building’s rating improves.
EWS1 problems are rarely straightforward, and they sit across several areas of law: conveyancing, service charges, the Building Safety Act, and the mortgage market’s own regulatory framework. Getting advice from solicitors who act across all of these, rather than from specialists in just one, tends to produce better outcomes.
