EWS1 Certificates: What They Are and How to Get One

EWS1 Certificates for High-Rise Flats: What They Are and How to Get One

If you own or are trying to buy or sell a flat in a UK high-rise, you've almost certainly heard of an EWS1 certificate. For thousands of leaseholders, it has been the single biggest obstacle to selling, remortgaging or simply understanding whether their home is safe. This guide explains what an EWS1 certificate is, which buildings need one, what the A1–B2 rating categories mean for your mortgage and sale prospects, and the five steps you can take if you're stuck.

For a broader guide to the fire safety obligations and qualifying leaseholder protections under the Building Safety Act 2022, see our cladding and EWS1 forms guide for buyers and leaseholders.

Why EWS1 Exists: From Grenfell to MHCLG Guidance

The Grenfell Tower fire in June 2017 killed 72 people and exposed catastrophic failures in the regulation of external wall systems on high-rise residential buildings. The subsequent Hackitt Review (2018) and the Ministry of Housing, Communities & Local Government (MHCLG) guidance in 2019 identified aluminium composite material (ACM) cladding as the most urgent risk — but also raised wider concerns about combustible insulation, timber cladding, high-pressure laminate panels and fire breaks within external wall systems.

In December 2019, UK Finance and the Building Societies Association agreed that mortgage lenders could not lend against flats in buildings with potentially combustible external wall systems without an assessment. The EWS1 (External Wall System Fire Review) form was created by RICS, UK Finance and the Building Societies Association as a standardised way for a competent professional to declare whether the external wall system is safe — or what remediation is needed before it can be considered so.

The A1–B2 Category System

The EWS1 form has four categories:

Category	What It Means	Mortgage/Sale Impact
A1	No combustible materials present in the external wall system	Lenders can proceed on standard terms
A2	Combustible materials present but low risk — no remediation needed	Most lenders will proceed; some may apply conditions
B1	Combustible materials present, but assessor is satisfied no remediation needed	Most lenders will proceed; some still decline
B2	Combustible materials present and remediation required	Mortgage typically refused until remediation complete

An A1 or A2 rating means your building's external wall system is considered safe, and most high-street lenders will lend. A B1 means the assessor is satisfied with risk controls but there are combustible elements — lender appetite varies, with some of the more cautious lenders still declining. A B2 is effectively unmortgageable until remediation is complete.

Which Buildings Need an EWS1?

This has been one of the most contested questions since 2019. The original position required EWS1 assessments for buildings above 18 metres (roughly six storeys). In 2021, RICS guidance extended the requirement to buildings above 11 metres in some circumstances, causing a wave of unsaleable flats in four- and five-storey blocks.

Following industry backlash and government pressure, RICS updated its guidance in 2022 and again in 2023 to introduce a more proportionate approach:

Buildings below 11 metres: EWS1 is generally not required
Buildings 11–18 metres: EWS1 may be required depending on the cladding type present — a qualified professional must make an initial assessment
Buildings above 18 metres: EWS1 is typically required for any mortgage transaction

As of 2024, lenders are not supposed to automatically require EWS1 for lower-rise buildings without specific grounds. If a lender is demanding one for a building under 11 metres with no obvious cladding concerns, it is worth challenging the request with reference to the current RICS guidance.

Who Can Sign Off an EWS1 Form?

This is critical — not just any fire engineer or building surveyor can sign an EWS1 form. The assessor must hold one of the following qualifications, depending on the work involved:

Category A assessments (no combustible materials): A Level 4 or higher fire risk assessor (or equivalent), registered on the EWS1 Assessors Register maintained by the relevant professional bodies
Category B assessments (combustible materials present): A chartered engineer with specific competency in fire performance of external wall systems, typically a member of IFE, CIBSE, IStructE or RICS with additional EWS1 qualification

The EWS1 Assessors Register was established in 2021 following concerns about unqualified individuals signing forms. You can search for a registered assessor via the RICS website. Using an unqualified assessor risks the form being rejected by lenders.

EWS1 Cost Table

Building Type	Typical EWS1 Assessment Cost
Small block (under 10 units, low rise)	£1,000–£2,000
Medium block (10–30 units, 4–6 storeys)	£2,000–£4,000
Large block (30–100 units, 6–12 storeys)	£3,000–£6,000
Complex or high-rise (100+ units or specialist cladding)	£6,000+
Intrusive investigation (opening up walls)	Add £1,000–£5,000

The cost is typically borne by the freeholder or management company, not individual leaseholders. If your freeholder is refusing to commission an EWS1 or is unreasonably delaying, this may be grounds for a complaint to the First-tier Tribunal.

What to Do If You're Stuck

The DLUHC Building Safety Fund

The Department for Levelling Up, Housing and Communities (DLUHC, now MHCLG) established the Building Safety Fund to cover the cost of remediating unsafe cladding on buildings above 18 metres. If your building has a B2 EWS1 rating and the developer no longer exists, the Building Safety Fund may cover remediation costs. Applications are managed via Homes England.

The Cladding Safety Scheme

For buildings between 11 and 18 metres, the Cladding Safety Scheme provides government funding for remediation where developers cannot be identified or are insolvent. Eligible buildings must have ACM or non-ACM combustible cladding.

Developer Remediation Contracts

Under the Building Safety Act 2022 and associated Developer Remediation Contracts, the UK's largest housebuilders — including Barratt, Taylor Wimpey, Bellway, Persimmon and around 50 others — committed to remediating unsafe buildings they constructed or refurbished since 1992. If your building was built by a major developer who signed the contract, you can register your building via the MHCLG portal.

Leaseholder Protections Under the Building Safety Act 2022

The Building Safety Act 2022 introduced significant protections for qualifying leaseholders:

Qualifying leaseholders (main home, owned before 14 February 2022) cannot be charged for cladding remediation costs
Non-cladding defect remediation costs are capped (the cap is linked to the property value and the year of purchase)
Landlords with net worth above £2 million cannot pass remediation costs to qualifying leaseholders

EWS1 Assessment Timeline

Stage	Typical Duration
Appoint registered assessor	1–4 weeks
Desktop review and initial assessment	1–2 weeks
Site inspection	1–2 weeks
Intrusive investigation (if required)	2–4 weeks
Report and EWS1 form issued	2–4 weeks
Total (straightforward)	6–12 weeks
Total (with intrusive investigation)	3–6 months

5 Practical Steps If You Need an EWS1

Check the EWS1 Assessors Register. Only appoint someone on the register. An unqualified assessment will be rejected by lenders and could result in wasted costs.
Contact your freeholder or managing agent in writing. Request confirmation of whether an EWS1 assessment has been commissioned. Keep a record — you may need it for a Tribunal application.
Check whether your developer signed a Remediation Contract. The MHCLG website lists all signatories. If yours is on the list, register your building via the developer portal.
Register for the Building Safety Fund or Cladding Safety Scheme. If your building is above 11 metres and the developer cannot fund remediation, register with Homes England.
Seek specialist legal advice if you are blocked from selling. A solicitor experienced in building safety law can advise on Tribunal remedies, lease extension complications and whether your leaseholder protections apply.

Practical Takeaways

An EWS1 is not a planning or building control document — it is a lender-driven risk assessment for the external wall system.
Only RICS-registered EWS1 assessors can sign the form. Category B assessments require a chartered engineer with specific fire competency.
A B2 rating means the property is unmortgageable until remediation is complete. Qualifying leaseholders are now legally protected from bearing those costs under the Building Safety Act 2022.
If your freeholder is dragging their feet, the First-tier Tribunal has powers to compel action.
Government remediation funding is available for buildings above 11 metres — don't assume you have to fund remediation yourself before exploring the Building Safety Fund and Cladding Safety Scheme.