Selling a Flat With Unsafe Cladding: What You Need to Know
You've accepted an offer. Then your buyer's solicitor asks for an EWS1 form and things come crashing to a halt.
If your building has cladding, this is one of the most common ways a flat sale falls through across England and Wales today. It isn't usually about whether your home is actually unsafe to live in day-to-day. Rather, it’s about whether a mortgage lender is willing to lend against it. And, as most buyers need a mortgage, that single question can decide whether your sale proceeds at all.
Within this post, we explain why cladding can stall sales, what protections exist for leaseholders, and what practical steps you can take to move a sale forward.
Why cladding stops a sale in its tracks
Since the Grenfell Tower fire in 2017, mortgage lenders have become much more cautious about lending on flats in buildings with combustible or unassessed external wall systems. If that system needs replacing, the value and safety of every flat in the block is affected, not just one.
That's the core problem for anyone trying to sell: it's rarely about your flat specifically. It's about the building. And a buyer's lender will want reassurance about the whole building before they'll release funds.
The EWS1 form, explained
The EWS1 (External Wall System) form is the document most lenders rely on to make that assessment. It was introduced in December 2019 by RICS, alongside UK Finance and the Building Societies Association, as a standard way for a qualified assessor to record the fire safety of a building's external walls.
A few things are worth knowing about it:
It isn't a legal requirement. No law says a building must have one. It's a lending tool, not a safety certificate. Though in practice, without one, many lenders simply won't proceed.
It comes with a rating. Ratings A1, A2 and A3 confirm no remediation is needed. B1 means some remedial work may be needed but lending can usually still proceed. B2 means combustible material has been identified and remediation is required. This is the rating that typically stops mortgage lending on a building until the work is done.
Not every building needs one. Government guidance has narrowed the circumstances in which lenders should request an EWS1. Buildings under 11 metres generally shouldn't need one; buildings between 11 and 18 metres only where specific risk factors are present; buildings over 18 metres are more likely to require one where cladding, balconies or rendered insulation are present.
If your building doesn't have a current EWS1 and your buyer's lender is asking for one, that's usually the first thing to establish: does the building actually need one under current guidance, and if so, who commissions it and how long will it take?
Your legal protections: the Building Safety Act 2022
The other piece of the picture is who actually pays for remediation work. Since the Grenfell Tower fire, a significant number of leaseholders have faced remediation bills for defects they had no part in creating. The Building Safety Act 2022 was introduced to change that, and it's worth understanding two documents it created, as both can come up during a sale.
The Leaseholder Deed of Certificate
This is a form you, as the leaseholder, complete to establish whether you have a "qualifying lease.” Meaning a long lease on your only or main home (or one of no more than three UK properties you own), granted before 14 February 2022, in a building over 11 metres or five storeys. If your lease qualifies, you're protected from paying for the removal of unsafe cladding, and your liability for other historical safety defects is capped or removed entirely, depending on your circumstances.
Without it on file, a landlord may be entitled to treat your lease as non-qualifying by default, which can leave you exposed to costs you'd otherwise be protected from.
The Landlord's Certificate
This is the document that runs the other way: your landlord confirms to you whether they meet certain financial and responsibility tests that determine who ultimately foots the bill for remediation. A landlord must provide one within four weeks of being told a lease is being sold, among other triggers. If you're planning to sell, requesting this early, rather than waiting for your buyer's solicitor to ask for it, can save weeks further down the line.
A note if you're in Wales: the Building Safety Act 2022 leaseholder protections described above apply in England. Wales has its own framework taking shape under the Building Safety (Wales) Act 2026, with the details of leaseholder cost protections currently out for consultation. If your building is in Wales, it's worth checking the current position with a solicitor rather than assuming the English rules apply directly.
What buyers, lenders and solicitors will actually ask for
When cladding is a known issue, expect your buyer's conveyancer to request some combination of:
A valid EWS1 form (or confirmation the building falls outside the scope where one is required).
Confirmation of the building's height and storey count, which determines which protections and requirements apply.
A Landlord's Certificate, confirming who is responsible for remediation costs.
Evidence of a funded remediation plan, if works are outstanding (including timescales and who's managing the project).
Confirmation of your own qualifying lease status, via a Leaseholder Deed of Certificate.
Gathering these in advance, before you go to market, generally moves a sale faster than reacting to requests once a buyer is already in the process.
Your options if you need to sell now
Get the paperwork moving before you list. If your building doesn't have an EWS1 and needs one, or if the Deed of Certificate and Landlord's Certificate haven't been exchanged, starting that process before you have a buyer avoids losing one further down the line to delays.
Ask where remediation stands. If your building has a B2 rating, the practical route to an unlocked sale is usually a funded, managed remediation programme through to a new EWS1. Buildings over 11 metres in England may be eligible for funding through the Cladding Safety Scheme or Building Safety Fund, which can mean the cost doesn't fall on leaseholders directly.
Consider a cash buyer if you need to move quickly. Some buyers (typically cash purchasers or investors) will proceed without an EWS1, since they aren't relying on mortgage finance. This narrows your buyer pool and will usually affect price, but it remains an option if timing matters more than maximising sale value.
Check for mortgage indemnity or insurance-backed alternatives. In some cases, insurance products exist that can satisfy a lender in place of a full EWS1 assessment. Availability and lender acceptance vary, so this is worth raising directly with a broker experienced in cladding-affected sales.
How professional remediation management moves things forward
For leaseholders and RTM/RMC directors dealing with an unresolved cladding issue, the practical bottleneck is rarely a lack of willingness to fix the problem. It's actually navigating the process: commissioning the right survey, applying for funding, appointing contractors, managing the works, and getting a new EWS1 issued at the end of it.
This is the role a specialist remediation management consultancy plays. Archway FM acts as Client Representative on cladding remediation projects, meaning we manage the process from initial assessment through to funding applications, contractor appointment and compliance oversight, right up until you get your final EWS1 certification. We don't carry out the physical construction work ourselves, but we manage those who do, on the leaseholders' or building owner's behalf, so the process moves without the building's management having to become full-time project managers.
If your building is stuck at any stage, whether waiting on a survey, unsure about funding eligibility, or without a clear route to a new EWS1, we're happy to talk it through and explain what the next step would look like for your building. Or, if you'd like to view some of our past projects, click here.