Selling a House with Subsidence: A Seller's Guide

Subsidence is one of the most anxiety-inducing words in residential property. If your home has a history of subsidence — whether an active claim, a resolved issue, or evidence of past underpinning — you may be wondering whether you can sell it at all, and if so, what it will cost you.

The short answer is that properties with subsidence histories are sold every day across England and Wales. But the process requires more preparation than a straightforward sale. Buyers, solicitors, surveyors, and mortgage lenders will all want reassurance that the issue is understood and managed. This guide walks you through what to expect, what to prepare, and how to keep your sale on track.

What is subsidence and why does it matter?

Subsidence is the downward movement of the ground beneath a building, causing part of the structure to sink. Unlike settlement, which is the gradual and generally uniform compression of soil under a new building's weight, subsidence is uneven and can cause significant structural damage if left unaddressed.

The most common cause of domestic subsidence in England and Wales is clay shrinkage. According to the British Geological Survey, approximately 43% of the land area in England and Wales is underlain by soils with shrink-swell potential. When clay soils dry out during prolonged hot weather, they shrink, pulling away from foundations. When they re-wet, they swell. This cyclical movement stresses the building's structure and can cause cracking, particularly in older properties with shallow foundations.

Other causes of subsidence include tree root activity (which accelerates clay drying), dissolved soluble rock such as chalk or gypsum, mining activity beneath the property, and defective drainage that washes away supporting soil. A ground stability search will flag many of these geological risks during the conveyancing process.

Your disclosure obligations as a seller

If you know your property has been affected by subsidence, you are legally required to disclose it. Section 7.4 of the TA6 Property Information Form asks whether the property has been affected by subsidence, landslip, or ground heave. You must answer this honestly, regardless of when the issue occurred or whether it has been fully resolved.

Beyond the TA6, your broader duty of disclosure means you should not conceal or misrepresent the property's structural history. Deliberately hiding subsidence — for example, by plastering over cracks before viewings without mentioning them — could amount to fraudulent misrepresentation under the Misrepresentation Act 1967. Our guide on what to disclose when selling covers your obligations in detail.

Being upfront about subsidence is not just a legal requirement — it is also a practical strategy. Buyers who discover undisclosed subsidence during their survey or searches will lose trust in the transaction. That loss of trust is one of the leading reasons sales fall through before exchange. Disclosing early, with supporting documentation, sets the right tone from the start.

How subsidence affects your buyer's mortgage

The buyer's ability to obtain a mortgage is often the biggest concern when selling a property with a subsidence history. Mortgage lenders assess the property as security for their loan, and any history of ground movement will receive close scrutiny.

Whether a lender will approve a mortgage depends largely on the current status of the subsidence:

The UK Finance Mortgage Lenders' Handbook sets out each lender's individual requirements for properties affected by subsidence. The buyer's solicitor will check these requirements as part of their conveyancing enquiries. If the lender's conditions cannot be met, the buyer may need to switch lenders or renegotiate the purchase.

Buildings insurance and subsidence

Buildings insurance is a prerequisite for any mortgage, and the availability and cost of insurance on a property with a subsidence history will directly affect your sale. The buyer needs to be able to obtain cover before their lender will release funds.

The Association of British Insurers (ABI) reports that the average domestic subsidence claim in the UK costs approximately 12,000 pounds to settle. This figure helps explain why insurers treat subsidence history carefully. However, insurance is available in most cases:

• Resolved subsidence with no underpinning. Most mainstream insurers will offer standard buildings insurance, potentially with a higher subsidence excess (often 1,000 to 2,500 pounds compared to the standard excess of a few hundred pounds) and a modest premium increase.
• Resolved subsidence with underpinning. Some mainstream insurers will cover underpinned properties; others will not. Specialist brokers such as those on the British Insurance Brokers' Association (BIBA) panel can help find appropriate cover. Premiums are typically higher than for non-subsidence properties.
• Active or recent subsidence claim. If the claim is still open, the current insurer generally continues to provide cover. However, the buyer may struggle to obtain a new policy from a different insurer until the claim is resolved. This can limit the buyer pool to cash purchasers.

As a seller, one of the most helpful things you can do is confirm that your own buildings insurance is active, includes subsidence cover, and has a documented claims history. Providing this information to the buyer's solicitor proactively can save considerable time during the enquiries process.

Key documents to prepare before listing

The difference between a smooth sale and a prolonged, stressful one often comes down to documentation. If your property has a subsidence history, gathering the following documents before you list will put you in the strongest possible position:

1. Certificate of structural adequacy. Issued by a chartered structural engineer (typically a Fellow or Member of the Institution of Structural Engineers), this confirms that the property is structurally sound following subsidence and any remedial work. This is the single most important document for reassuring buyers and lenders.
2. Monitoring records. If crack monitors or telltale gauges were installed, the monitoring reports should show that movement has stabilised. The Building Research Establishment (BRE) recommends a minimum of 12 months' monitoring covering at least one full seasonal cycle.
3. Insurance claim history. A record of any subsidence claims made, including the cause, the remedial action taken, and the outcome. Your insurer can provide this on request.
4. Underpinning certificates. If the property was underpinned, the completion certificate and any associated guarantees should be included. Some underpinning methods carry insurance-backed warranties.
5. Tree reports. If the subsidence was caused by tree roots, a report from a qualified arborist confirming that the trees have been removed or managed appropriately is valuable.
6. Drainage surveys. If defective drainage was a contributing factor, evidence that repairs have been completed will help address buyer concerns.
7. Current buildings insurance schedule. Confirming that subsidence cover is in place and noting the terms, excess, and any special conditions.

Having these documents ready before your buyer's solicitor raises enquiries can shave weeks off the conveyancing timeline. Many of the delays in selling a property with subsidence arise not from the subsidence itself, but from the time it takes to locate and compile the necessary paperwork after a buyer is already waiting.

The conveyancing process: what to expect

Selling a property with a subsidence history follows the same conveyancing process as any other sale, but with additional layers of scrutiny. Here is how the key stages typically play out:

1. You complete your TA6 form. You disclose the subsidence history in Section 7.4 and provide as much detail as possible, including dates, causes, and remedial work carried out.
2. The buyer commissions a survey. The surveyor will inspect the property for signs of structural movement and review any documentation you have provided. A Level 3 (Building Survey) is more likely than a Level 2 (HomeBuyer Report) given the subsidence history.
3. Property searches flag ground risks. The buyer's solicitor orders property searches, which will likely include an environmental search with a ground stability assessment. Any geological risks beneath the property will be identified.
4. The buyer's solicitor raises enquiries. Expect detailed questions about the subsidence history, remedial works, monitoring results, insurance claims, and current structural condition. Your solicitor will send your prepared documentation in response.
5. The mortgage lender assesses the property. The lender's valuer may request additional information or a specialist valuation. The lender checks their handbook requirements for subsidence-affected properties.
6. Insurance is confirmed. The buyer obtains buildings insurance with subsidence cover. The lender confirms this meets their requirements.
7. Exchange and completion proceed. Once all enquiries are satisfied and the lender has issued a formal mortgage offer, the sale moves to exchange in the usual way.

The additional steps can add 2 to 6 weeks to the standard conveyancing timeline, depending on how quickly documentation is provided and how responsive the various parties are. Sellers who prepare their paperwork in advance typically experience delays at the shorter end of this range.

Common causes of subsidence and their implications for sellers

Understanding the specific cause of your property's subsidence helps you prepare for the questions buyers and their advisers will ask. The table below sets out the most common causes and what each means in practical terms for your sale.

Underpinning: what buyers need to know

If your property has been underpinned, buyers will have additional questions. Underpinning strengthens the foundations to prevent further movement, and it is generally a sign that the subsidence was taken seriously and properly remediated. However, the word carries a stigma that can deter some buyers and restrict mortgage options.

The key facts to communicate are:

• What type of underpinning was carried out. Traditional mass concrete underpinning involves excavating beneath existing foundations and pouring new, deeper foundations in stages. Modern methods such as resin injection (geopolymer stabilisation) are less invasive and increasingly accepted by lenders.
• Who carried out the work. Work completed by a reputable specialist contractor, ideally a member of a recognised trade body, provides more reassurance than undocumented DIY efforts.
• Whether a guarantee or warranty was issued. Some underpinning methods come with insurance-backed guarantees of 10 to 25 years. If a guarantee exists, include it in your documentation pack.
• Whether a certificate of structural adequacy exists. This is the gold standard for underpinned properties. Without it, the buyer's lender may refuse to proceed.

Not all lenders will accept underpinned properties. According to guidance published by the Royal Institution of Chartered Surveyors (RICS), surveyors should assess underpinned properties on their individual merits rather than applying a blanket downvaluation. In practice, however, some lenders have restrictive policies, and buyers may need to shop around or use a broker to find a suitable mortgage product.

Indemnity insurance and subsidence

In some circumstances, indemnity insurance can be used to address specific subsidence-related concerns during conveyancing. For example, if the ground stability search flags a theoretical risk of dissolution or mining subsidence but there is no evidence of actual movement, an indemnity policy can protect the buyer and their lender against future costs.

However, indemnity insurance is not a substitute for proper investigation where there are visible signs of subsidence or an active claim. It works best for theoretical or geological risks that have not yet materialised, not for properties where subsidence has already occurred. Where subsidence has happened, the buyer and lender will want physical evidence — monitoring data, engineer's reports, and completion certificates — rather than an insurance policy covering a hypothetical risk.

Pricing your property realistically

Subsidence history does not automatically mean you need to accept a significantly lower price, but it does mean you need to be realistic about the market for your property. Several factors affect the price impact:

• Resolution status. A property with fully resolved subsidence, strong documentation, and a certificate of structural adequacy may sell within 5% to 10% of its unaffected market value. Active or unresolved subsidence will command a larger discount.
• Local prevalence. In areas where subsidence is common — much of London and the Home Counties sits on clay — buyers and their advisers are more familiar with the issue and less likely to be deterred. In areas where subsidence is rare, the stigma can be greater.
• Documentation quality. Comprehensive, well-organised documentation reassures buyers and supports the asking price. Missing records raise doubts and give buyers leverage to negotiate harder.
• Buyer type. Mortgage-dependent buyers have less flexibility because their lender dictates what is acceptable. Cash buyers can move faster and may accept properties that lenders will not, but they typically expect a discount to reflect the additional risk they are taking on.

Your estate agent should have local experience of selling properties with structural histories. Ask them for evidence of comparable sales and be wary of agents who either drastically undervalue your property because of the subsidence or ignore the issue when setting the asking price.

Practical steps to prepare for your sale

If you are planning to sell a property with a subsidence history, here is a practical checklist to follow before listing:

1. Gather all subsidence-related documentation. Collect monitoring reports, structural engineer's certificates, insurance claim records, underpinning certificates, tree reports, and drainage surveys. Organise them chronologically.
2. Confirm your buildings insurance status. Check that your current policy includes subsidence cover and note the terms, excess, and any exclusions. Obtain a copy of your claims history from your insurer.
3. Complete your TA6 form thoroughly. Answer Section 7.4 in full, providing dates, details, and cross-referencing the documentation you have gathered. Thorough disclosure here prevents delays later.
4. Consider obtaining a fresh structural report. If your certificate of structural adequacy is more than 5 to 10 years old, a fresh inspection by a chartered structural engineer can reassure buyers that no new movement has occurred.
5. Instruct your solicitor early. Brief your solicitor on the subsidence history before you accept an offer. They can review your documentation, identify any gaps, and prepare responses to the enquiries they know will be raised.
6. Be transparent with your estate agent. Your agent needs to know about the subsidence history to manage buyer expectations honestly and avoid wasted viewings with buyers who cannot proceed.

What if the subsidence is not yet resolved?

Selling a property with active or ongoing subsidence is harder, but not impossible. Your options include:

• Wait until the claim is resolved. If your insurer is investigating and monitoring is under way, waiting until you have a certificate of structural adequacy will significantly widen your buyer pool and improve the price you achieve.
• Sell to a cash buyer. Cash buyers do not need mortgage approval, which removes the biggest barrier. However, expect a discounted offer to reflect the risk and cost the buyer is taking on.
• Sell at auction. Auction sales attract experienced investors and cash buyers comfortable with non-standard properties. The certainty of exchange on the day can be attractive, but the sale price may be lower than private treaty.
• Complete the remedial works yourself. If you have the resources, completing the investigation, monitoring, and any necessary remedial work before listing allows you to sell with the issue fully behind you.

Structural enquiries: what buyers ask about subsidence

If the buyer's survey flags structural movement, or your TA6 discloses a history of subsidence, the buyer's solicitor will raise detailed structural enquiries as part of the conveyancing process. These questions are designed to establish the full picture of what happened, what was done about it, and whether the issue is truly resolved. Being prepared for them — and responding promptly with comprehensive documentation — is one of the most effective ways to keep your sale on track.

Typical structural enquiry questions include:

• Has the property ever suffered from subsidence, heave, or landslip?
• Has the property been underpinned? If so, when and by whom?
• Has a structural engineer's report been obtained? Please provide a copy.
• Has any insurance claim been made for structural damage? Please provide the claim reference and outcome.
• Is there an ongoing monitoring regime?
• Has the cause of movement been identified and resolved?

When responding to these enquiries, the key is to provide full documentation rather than brief answers. Your solicitor should supply copies of the structural engineer's reports, all insurance claim correspondence including the claim reference and outcome, completion certificates for any underpinning work, and monitoring records showing that movement has stabilised.

If the subsidence was historic and has been fully resolved, emphasise this clearly in your responses and back it up with supporting evidence — a certificate of structural adequacy, stable monitoring data, and confirmation that the original cause has been addressed. A well-evidenced response to structural enquiries can turn what initially looks like a red flag into a point of reassurance for the buyer.

It is also worth noting that most insurers will cover a property with a resolved subsidence history, although the buyer may face higher premiums or a larger excess on their buildings insurance policy. Being able to demonstrate that your own insurance has remained in place with subsidence cover throughout your ownership provides helpful context.

If the property has been underpinned, provide the contractor's guarantee and any sign-off from a chartered structural engineer confirming that the work was completed satisfactorily. Buyers and their solicitors will want to see that the underpinning was carried out by a reputable specialist and that the foundations have been stable since the work was done. Our guide on common survey issues explains how structural concerns raised in a survey typically feed into the enquiries process.

Sources and further reading

• Association of British Insurers (ABI) — Guidance on domestic subsidence claims and insurance: abi.org.uk
• Building Research Establishment (BRE) — BRE Digest 251: Assessment of damage in low-rise buildings with particular reference to progressive foundation movement
• British Geological Survey (BGS) — Shrink-swell hazard mapping and GeoSure ground stability data: bgs.ac.uk/geology-projects/shrink-swell
• Royal Institution of Chartered Surveyors (RICS) — Guidance on the assessment of subsidence and underpinning for residential property: rics.org
• Institution of Structural Engineers (IStructE) — Guidance on certificates of structural adequacy: istructe.org
• UK Finance — Mortgage Lenders' Handbook, individual lender requirements for subsidence-affected properties: lendershandbook.ukfinance.org.uk
• Law Society — TA6 Property Information Form guidance notes: lawsociety.org.uk
• Coal Authority — Interactive map of coal mining reporting areas and CON29M search information: coalauthority.gov.uk

Related guides

• Selling a House with Aluminium Wiring
• Selling a House with a Retaining Wall
• Selling a House with Flood Risk in South Yorkshire

Frequently asked questions