Sell an Unmortgageable House: Subsidence, Short Lease, Cladding and More
Why "unmortgageable" is a lender problem, not a you problem
A property becomes unmortgageable when a mainstream lender’s surveyor will not approve a loan against it, most often because of subsidence, a short remaining lease, cladding or fire safety works, or a non-standard method of construction. None of this reflects on you as a seller. It reflects on how mortgage lenders assess risk, which is conservative by design and often more cautious than the property genuinely warrants. The practical effect is the same regardless of cause: a large share of the open market, anyone needing a mortgage, is closed to your buyer before they even view the property. That is the gap a cash purchase closes, because we do not need mortgage finance to complete.
The four issues we see most often
Subsidence is ground movement that causes a building’s foundations to shift, typically from clay soil shrinkage, tree root activity or nearby drainage problems. The Association of British Insurers recorded roughly 9,000 households supported by new subsidence claims in the first half of 2025 alone, with the average claim reaching a record £20,000 by the second quarter of 2026 (ABI, press releases, August 2025 and August 2026). A history of a subsidence claim, even one fully resolved, is often enough for a mainstream lender to decline or heavily restrict a mortgage.
A short lease, generally one with 80 years or fewer remaining, triggers “marriage value” costs on lease extension and makes many mainstream lenders unwilling to lend, since their security weakens as the lease runs down. Around 412,000 households in England currently live in a property with 80 years or less left on the lease, of which 204,000 are owner-occupiers (GOV.UK, Leasehold Term Remaining 2023 to 2024, updated June 2026), out of a total leasehold stock of 4.9 million dwellings in England (GOV.UK, Leasehold Dwellings 2024 to 2025, published May 2026).
Cladding and EWS1 requirements affect flats in buildings identified as having unsafe external wall systems following the post-Grenfell building safety reforms. Thousands of flats across England remain affected while remediation works are completed or an EWS1 form is obtained, and many mainstream lenders will not lend against a flat until that certification is in place, regardless of the flat’s own condition.
Non-standard construction, prefabricated concrete, steel-framed or timber-framed homes built outside typical brick-and-block methods, falls outside many lenders’ standard criteria entirely, independent of the property’s actual condition or age.
An honest offer, not a lowball because you are stuck
Our offer is made in writing and does not change unless a significant undisclosed defect is identified by survey. We know sellers of unmortgageable properties are sometimes targeted with unrealistically low first offers on the assumption they have no other buyers. We price from the property’s actual condition and a realistic view of what it is worth to us as a cash purchase, not from how limited we think your options are.
Rob’s advise:
“Subsidence is the one that catches sellers out most, because the damage itself is often minor and the house is perfectly liveable, but a single historic insurance claim on the file is enough for a mainstream lender’s surveyor to decline outright. We bought a property last year where the subsidence had been monitored and stable for over a decade, with engineer’s reports to prove it, and the seller had still had three separate mortgage buyers fall through before they came to us. We did not need a mortgage survey, so the engineer’s history was useful context for our own offer, not a reason to walk away. That is the difference a cash purchase makes on properties like this: the same facts that scare off a high-street lender do not scare off a cash buyer who is actually looking at the property, not just running it through standard lending criteria.”
What happens after you enquire
We arrange a visit or a detailed remote assessment depending on the issue, make a written offer within 24 hours, and work to your timeline from there, typically 7 to 28 days to completion. Because there is no mortgage lender in the chain, there is no survey that can unexpectedly kill the sale weeks after you thought it was agreed, which is the single most common way these sales collapse on the open market.
Questions people ask us
What makes a house unmortgageable?
Most commonly subsidence history, a short lease (generally 80 years or fewer remaining), cladding or fire safety issues requiring an EWS1 form, or non-standard construction methods a lender’s criteria do not cover. A lender’s own risk appetite, not the property’s genuine condition, usually decides the outcome.
Can I sell a house with subsidence in the UK?
Yes. A cash sale does not require a mortgage survey, so a subsidence history, even an ongoing or recently settled claim, does not block the sale the way it typically blocks a mortgage-backed buyer.
How many years does a lease need for a mortgage?
Most mainstream lenders want at least 70 to 85 years remaining at the point of purchase, and some set the bar even higher. Around 412,000 households in England currently live in properties at or below the 80-year threshold (GOV.UK, June 2026), which is exactly the group this page is written for.
Can I sell a flat affected by cladding without an EWS1 form?
Selling to a mainstream mortgage buyer without an EWS1 form is very difficult while your building’s remediation status is unresolved. A cash sale does not require the form, because there is no mortgage lender in the chain to demand it.
What is non-standard construction and does it affect selling?
Non-standard construction covers homes built using methods other than traditional brick-and-block, including prefabricated concrete, steel-framed and timber-framed properties. Many mainstream lenders decline or heavily restrict lending on these regardless of the property’s actual condition, which narrows the mortgaged-buyer pool considerably.
Will I get a fair price if my house is unmortgageable?
Our offer is made in writing and does not change unless a significant undisclosed defect is identified by survey. We price from the property’s real condition, not from an assumption that a seller with fewer options will accept less.
Do I need a survey before selling to a cash buyer?
No mortgage survey is required, since we are not relying on mortgage finance to complete. We carry out our own assessment before making an offer, which is a different process and does not carry the same risk of unexpectedly collapsing the sale.
How quickly can an unmortgageable property sell for cash?
Typically 7 to 28 days from accepted offer to completion, depending on the property, any chain beneath you, and how quickly your solicitor can turn around the legal work.
