Woodworm Treatment Certificate When Selling

When a buyer's solicitor asks for documentation about woodworm, they are not simply asking whether the property has had a problem — they are asking for proof that the problem was dealt with professionally, that the work meets a recognised standard, and that the buyer will be protected if anything goes wrong after they move in. The woodworm treatment certificate and its accompanying guarantee are the documents that provide that reassurance.

For sellers, understanding exactly what a certificate should contain, why it matters during conveyancing, and what to do if you cannot find it is essential preparation. This guide covers the certificate in detail — what it records, how guarantees work, how to replace a lost certificate, and when indemnity insurance is an appropriate substitute.

If you are looking for broader guidance on selling with an active or historic infestation, see our companion guide on selling a house with woodworm.

What a woodworm treatment certificate should contain

A woodworm treatment certificate issued by a reputable, PCA-accredited contractor should be a clear, comprehensive document. It is not a standardised government form, so the layout varies between contractors, but the following information should always be present:

A certificate that is missing any of the above — particularly the species, treated areas, or guarantee details — may not satisfy the buyer's solicitor or their mortgage lender. If your certificate is incomplete, contact the issuing contractor to provide a replacement or supplementary letter.

How the guarantee works

The guarantee that accompanies a woodworm treatment certificate is what gives the document most of its value during a property sale. Understanding exactly what the guarantee covers — and what it does not — helps sellers answer buyer enquiries confidently.

What the guarantee covers

A standard woodworm treatment guarantee covers the re-infestation of the same species of wood-boring beetle in the areas treated, within the guarantee period. If common furniture beetle returns to the sub-floor joists that were sprayed five years ago, the contractor is obliged to re-treat at no charge. Some guarantees also cover structural repairs to timbers that are found to have been weakened by the infestation, though this varies between contractors.

What the guarantee does not cover

Guarantees typically exclude:

• New infestations by a different species of beetle to the one originally treated
• Damage caused by damp, rising moisture, or fungal decay that encourages reinfestation by providing the beetle with its preferred conditions
• Areas of the property that were not treated during the original visit
• Timber that has been altered, extended, or interfered with after the treatment date
• Damage from other structural causes, such as subsidence or impact damage

These exclusions matter when you are answering buyer enquiries. If a buyer asks whether the guarantee covers the whole property, you should be able to point to the specific areas listed in the certificate rather than making a general assurance.

Insurance-backed guarantees

The most robust guarantees are backed by an insurance policy administered through a scheme approved by the PCA. If the original contractor ceases trading — for any reason, including insolvency — the insurance company steps in to honour the remaining guarantee period. This gives the buyer a level of protection that a standalone contractor guarantee cannot provide.

The PCA requires its members to provide insurance-backed guarantees (IBGs) on all qualifying timber treatment work. When instructing a contractor, always confirm whether their guarantee is insurance-backed and ask for the policy reference number. Without an IBG, the guarantee is only as durable as the contractor's business.

Why the certificate matters to buyers and their solicitors

Buyers and their solicitors are primarily concerned with risk. When a property has had woodworm, the questions they need answered are: was the treatment effective, is the problem likely to return, and is there any financial protection if it does? The treatment certificate and guarantee answer all three questions.

Reassurance for the buyer

A buyer who receives a certificate from a PCA-accredited contractor with a 20-year insurance-backed guarantee knows that a regulated professional assessed and treated the problem, that the work met an industry standard, and that there is a claims process if the infestation recurs. This transforms woodworm from an open-ended risk into a documented and managed issue — significantly reducing the likelihood of renegotiation or withdrawal.

Reassurance for the mortgage lender

Mortgage lenders can be more cautious than buyers. If the lender's valuation surveyor flags woodworm, the lender may require evidence of professional treatment before releasing funds. A current treatment certificate with a transferable guarantee from a PCA-accredited contractor is usually sufficient to satisfy this requirement. Without it, the lender may impose a retention on the mortgage — withholding a portion of the loan until the woodworm is dealt with — which can cause complications at completion if the buyer does not have the funds to bridge the gap.

Effect on conveyancing enquiries

If woodworm has been disclosed on the TA6 Property Information Form or identified in a survey, the buyer's solicitor will raise specific enquiries. Providing the certificate promptly, along with the guarantee document and any specialist timber survey reports, allows your solicitor to respond fully and efficiently. Delays in providing documentation are one of the most common causes of conveyancing slowdowns — having the paperwork ready before exchange saves time and reduces the risk of the buyer losing confidence.

How the certificate transfers when you sell

One of the most important practical questions is how the woodworm treatment guarantee passes to the buyer. The process is usually straightforward but requires some attention.

Automatic transfer

Most PCA-accredited guarantees transfer automatically to the new owner on completion of the sale. The buyer inherits the remaining years of cover without needing to apply or pay any additional fee. Your solicitor will include the original certificate and guarantee documents in the property certificate pack passed to the buyer's solicitor during conveyancing.

Notification requirements

Some guarantees require the contractor or guarantee provider to be notified when the property changes hands. Check the terms of your certificate carefully. If a notification is required, instruct your solicitor to send written notification to the issuing company on or around the completion date. Failure to notify can, in some cases, invalidate the transfer of cover, though this is rare for PCA insurance-backed guarantees.

What the buyer should retain

At completion, the buyer's solicitor should receive the original treatment certificate, the guarantee document (which may be a separate document from the certificate), any specialist timber survey reports, and a copy of any correspondence between you and the contractor. If you can also provide details of the contractor's PCA membership and the insurer's contact information, this is helpful but not essential.

What to do if you cannot find the certificate

Losing a woodworm treatment certificate is a common problem. Properties change hands several times over decades, paperwork gets lost, and contractors change names or close. If you cannot locate the certificate, work through the following steps before concluding that it is irretrievable:

1. Contact the original contractor. If you know the company's name, call or email them directly. Most contractors retain job records for the duration of the guarantee period and can issue a replacement certificate, sometimes for a small administration charge.
2. Search the PCA database. The Property Care Association maintains a register of guarantees issued by its members. If the original contractor was PCA-accredited, the guarantee may be on the database and can be retrieved by providing the property address and approximate date of treatment.
3. Check your conveyancing file. If the treatment predates your ownership, the certificate should have been included in the documents you received from your solicitor when you purchased the property. Contact your conveyancing solicitor, as firms are required to retain files for at least six years and many keep them for considerably longer.
4. Ask your mortgage lender. If your mortgage lender required the treatment as a condition of the original loan, they may hold a copy of the certificate on their file. Contact your lender's deeds department or mortgage records team.
5. Check your own property documents. Review the paperwork you received at purchase, including the solicitor's completion statement, the surveyor's report, and any correspondence from the seller's solicitor. The guarantee was a required disclosure and should appear somewhere in the transaction documents.

If none of these steps succeed, you have two practical options: arrange a new specialist timber survey or obtain indemnity insurance.

Commissioning a new timber survey

If the original certificate cannot be located and the buyer or their mortgage lender requires current evidence of the timber condition, commissioning a new specialist timber survey is often the cleanest solution. A PCA-accredited timber surveyor will inspect all accessible timbers, determine whether any woodworm is active, assess the extent of any structural damage, and provide a written report.

If the survey concludes that the property is free from active woodworm and any historic damage is not structurally significant, the report effectively serves as a substitute for the original certificate in reassuring the buyer and their lender. A timber survey typically costs between £150 and £400, depending on the size of the property and the depth of investigation required.

If the survey identifies an active infestation, you will need to arrange professional treatment and obtain a new certificate before proceeding. For more on the treatment options and how to approach negotiations after a survey finds woodworm, see our guide on selling a house with woodworm.

Indemnity insurance as an alternative

Where the original certificate cannot be found and the property shows no current signs of active woodworm, indemnity insurance is the most widely used alternative in conveyancing. Your solicitor can arrange the policy quickly and it is a recognised solution that most buyers and mortgage lenders will accept.

How the policy works

The policy covers the buyer and their mortgage lender against the financial cost of remedial work if the woodworm infestation recurs and the original guarantee cannot be relied upon because the certificate is missing. It lasts indefinitely, transfers automatically to future owners, and requires no ongoing premiums after the initial one-off payment.

Typical cost

Indemnity insurance for a missing woodworm treatment certificate typically costs between £40 and £120 as a one-off premium, depending on the value of the property and the level of cover required. This is usually paid by the seller, though it is negotiable. Costs are low relative to the alternative of commissioning a new survey or re-treating the property.

When indemnity insurance is not appropriate

Indemnity insurance cannot be used if there are any current signs of active woodworm in the property — for example, if fresh bore dust or recently emerged exit holes have been found. Insurers will not cover a known existing defect. If the buyer's survey has flagged active woodworm, the infestation must be treated by a PCA-accredited contractor and a new certificate obtained before the sale can complete on standard terms.

There is also a sequencing requirement: indemnity insurance must be arranged before any formal enquiries are made of the contractor or the PCA about the missing certificate. Once you have raised the issue formally, insurers may decline to cover it. Your solicitor will manage this sequencing as part of the conveyancing process. For broader context on how indemnity insurance works in property transactions, see our guide on the property certificate pack.

Disclosure on the TA6 Property Information Form

Whether or not you have the certificate to hand, you are legally required to disclose known woodworm treatment on the TA6 Property Information Form. The TA6 is the standard seller's questionnaire in England and Wales and includes specific questions about property defects, alterations, and any guarantees or warranties relating to the property.

The relevant sections require you to confirm whether any timber treatment has been carried out, the approximate date, the contractor's name, and whether a guarantee was provided. You should also state whether you hold the certificate or whether it has been lost, and what steps you have taken to locate it.

Deliberately omitting known woodworm treatment from the TA6 is misrepresentation. A buyer who discovers after completion that you knew about a woodworm history and failed to disclose it could pursue a legal claim for damages against you. The safest approach is always to disclose what you know and explain the position clearly — your solicitor can help you frame the disclosure in a way that does not alarm the buyer unnecessarily.

For a full guide to completing the TA6 accurately and minimising the risk of misrepresentation claims, see what is a TA6 form.

Costs at a glance

Practical checklist for sellers

If your property has had woodworm treatment at any point, work through the following checklist before marketing:

1. Locate the original treatment certificate and guarantee document. Check your property files, previous conveyancing paperwork, and any home information pack documents.
2. Check the guarantee expiry date. If the guarantee has not yet expired, confirm that it is transferable and note whether notification to the contractor is required on sale.
3. If the certificate is missing, contact the original contractor or the PCA database before taking any other steps.
4. If the contractor cannot be traced and the PCA database does not hold the record, speak to your solicitor about indemnity insurance. Do this before raising any formal enquiries.
5. Inspect accessible timbers for signs of active woodworm: fresh bore dust, clean-edged exit holes, or visible frass beneath affected areas. If you find anything suspicious, commission a specialist timber survey before marketing.
6. Complete the TA6 form honestly, disclosing all known treatment history and the current status of the certificate and guarantee.
7. Prepare your documentation early so that when enquiries are raised by the buyer's solicitor, your solicitor can respond promptly. Slow responses to timber-related enquiries are a common source of delay in residential conveyancing.

For a full overview of the other documents you will need to assemble before exchange, see our guide on the hidden costs of selling a house, which covers the financial preparation involved in getting a property to market.

Sources

• Property Care Association (PCA) — property-care.org
• Royal Institution of Chartered Surveyors (RICS) — rics.org
• Building Research Establishment (BRE) — bregroup.com
• Law Society — TA6 Property Information Form, 5th edition, 2020
• GOV.UK — Building Regulations, Approved Document to support Regulation 7 (timber preservation in areas affected by house longhorn beetle): gov.uk
• Historic England — Guidance on managing wood-boring beetles in historic buildings: historicengland.org.uk

Related guides

• Timber Treatment Guarantee for Sellers

Frequently asked questions