The short answer
Yes. When selling a home in England and Wales you must disclose underpinning and any history of subsidence on the TA6 Property Information Form, which specifically asks about structural movement and related building work. You have a legal duty not to give false or misleading answers, and answering 'no' or 'not known' when you do know can amount to misrepresentation. Hiding underpinning rarely works in practice anyway, because it usually surfaces through the buyer's survey, local searches, insurance enquiries and building-control records. If a buyer discovers concealed underpinning after completion, they may be able to claim against you for damages or even rescind the sale. Full, early disclosure — with the supporting paperwork — is both the legal requirement and the practical way to keep a sale on track.
Some sellers worry that declaring underpinning will scare buyers off, but non-disclosure is far riskier. The sections below explain exactly where you disclose it, what the law expects, and what can go wrong if you don't.
Disclosure facts
- Must you disclose?Yes (England & Wales)
- WhereTA6 Property Information Form
- Legal dutyNo false or misleading answers
- If hiddenRisk of misrepresentation claim
- Best practiceDisclose early, with documents
Where and how you declare it
In a standard conveyancing transaction in England and Wales, the seller completes the TA6 Property Information Form as part of the contract pack their solicitor sends to the buyer's solicitor. The TA6 asks directly about whether the property has been affected by structural movement, subsidence, heave or landslip, and whether any related building work, repairs or insurance claims have taken place. Underpinning falls squarely within these questions. You answer honestly and attach the supporting documents — the Certificate of Structural Adequacy, building-control completion certificate, any guarantees, and details of insurance and past claims. Your conveyancer can advise on the precise wording, but the principle is simple: tell the buyer what you know.
The legal duty not to mislead
Property sales in England and Wales operate on the principle that a seller must not make false or misleading statements, even though there is no general duty to volunteer every fact. Once a question is asked — and the TA6 asks about movement and works — you must answer it truthfully. Key points:
- 'I forgot' is weak. If you arranged or lived through the underpinning, you knew about it.
- 'Not known' must be genuine. Ticking 'not known' to dodge a true answer can itself be misleading.
- Misrepresentation has consequences. A buyer relying on a false answer who suffers loss may claim damages, and in serious cases seek to unwind the sale.
If you are genuinely unsure whether older work counts as underpinning, say so and let your solicitor and the buyer investigate, rather than guessing in your favour.
What counts as movement you must disclose
The TA6 asks about more than just formal underpinning, so it helps to know what falls within an honest answer:
- Underpinning or foundation works carried out by you or, to your knowledge, a previous owner.
- Any subsidence, heave or landslip the property has experienced, even if it did not lead to underpinning.
- Insurance claims made for structural movement, and the outcome.
- Repairs to cracks or structural damage linked to movement, and any guarantees attached.
- Ongoing monitoring or unresolved issues you are aware of.
If you are unsure whether something historic qualifies — for example, work done long before you owned the home — the safe course is to disclose what you know and let the buyer's solicitor investigate, rather than deciding in your own favour. Your conveyancer can help you phrase an accurate answer where the facts are incomplete. Honesty about uncertainty is very different from a confident 'no' that later proves false.
Disclosure helps the sale, not just the law
Beyond the legal duty, early disclosure is good tactics. A buyer who learns about underpinning at the outset, with a tidy pack of documents proving it was done properly and the home is stable, can price it in and proceed with confidence. A buyer who discovers it midway through — after paying for searches and a survey — feels misled, loses trust, and is far more likely to renegotiate hard or walk away. Disclosing also lets the buyer's lender and insurer assess the property properly from the start, avoiding a late refusal that derails everything. In short, the same honesty the law requires is also what keeps the transaction moving and reduces the chance of a costly fall-through.
Frequently asked questions
What happens if I don't declare underpinning?
If you give a false or misleading answer on the TA6 and the buyer relies on it, they may bring a misrepresentation claim after completion, seeking damages or, in serious cases, to rescind the sale. Concealment also tends to surface through surveys, searches and insurance enquiries, often collapsing the sale before it completes.
Does underpinning show up in searches?
Underpinning often appears via building-control records, and any subsidence history can show in insurance enquiries the buyer's solicitor and insurer make. A surveyor may also spot physical signs. Combined with the buyer's questions, this means underpinning is usually discoverable regardless of what the seller says.
Do I have to declare underpinning done by a previous owner?
If you are aware of it, yes — the TA6 asks what you know about the property's movement and works, not only what you personally commissioned. Pass on any documents you hold from the previous owner. If you genuinely do not know, your solicitor can advise on answering accurately.
Sources & further reading
Figures on this page are typical UK ranges drawn from published sources and depend on your specific property. They are guidance, not a quotation.