Woodworm or Dry Rot Found in Your Survey? What It Means and What to Do Next

When a RICS surveyor flags woodworm or dry rot in your house survey report, it does not automatically mean the purchase should fall through. Many findings are historic, pose little structural risk, and can be resolved through treatment, a specialist report, and negotiation. The key question is whether the infestation is active — and what it has done to the timber around it.

What the Survey Report Is Actually Telling You

Woodworm is the collective name for the larvae of wood-boring beetles, most commonly the common furniture beetle (Anobium punctatum). The larvae burrow through timber as they feed, leaving behind small round exit holes — typically 1–2 mm in diameter — and a fine powdery dust called frass.

Surveyors are trained to spot these signs during a Level 2 or Level 3 building survey. When they note 'evidence of woodworm' in your report, they are recording what they can see. Crucially, they are not always confirming whether an infestation is currently active. That distinction matters — and it determines what happens next.

Active vs Historic Woodworm: The Critical Difference

Not all woodworm findings carry the same risk. Many older properties carry the physical signs of a past infestation that has long since died out, often following a previous timber treatment.

Signs that suggest active woodworm include:

• Fresh exit holes with clean, pale edges rather than darkened, aged ones

• Fine powdery frass that falls freely from the timber

• Live larvae visible where timber has been recently broken or opened

• Exit holes appearing in areas not previously noted in earlier surveys

Historic woodworm, by contrast, typically shows older, darkened exit holes with no fresh frass and timber that remains structurally sound. A specialist damp and timber survey — costing between £190 and £490 for a standard property — will clarify which you are dealing with and produce a remediation scope if treatment is needed.

Dry Rot: When the Timber Finding Is More Serious

If your surveyor mentions dry rot (Serpula lacrymans), the concern is usually greater than woodworm alone. Dry rot is a fungal decay that feeds on the structural components of timber and, critically, can spread through masonry and across gaps without direct contact with a moisture source.

A surveyor will look for:

• Timber that crumbles easily into cube-shaped pieces

• A distinctive mushroom-like smell in confined spaces

• White or grey cotton-wool-like mycelium growth on surfaces

• Orange or reddish-brown fruiting bodies, known as sporophores

Dry rot remediation is more involved than woodworm treatment. It requires identifying and removing the moisture source, cutting out all affected and at-risk timber, treating surrounding masonry, and replacing structural members where necessary. Costs vary significantly with the extent of the spread.

How to Respond When Timber Defects Are Flagged

If woodworm or dry rot appears in your survey report, these are the recommended next steps before you exchange contracts:

• Request a specialist damp and timber survey from a qualified treatment company — this produces a scope of works, a remediation plan, and a treatment guarantee

• Obtain a written quotation for the works so you have a figure for negotiation

• Ask your solicitor to include the specialist report in the conveyancing process

• Use the quotation to negotiate a price reduction or to request that the seller completes the works prior to exchange

• Confirm that any completed treatment comes with a 20–30 year guarantee, as most mortgage lenders require this

Do not accept verbal reassurances. Any remediation affecting the structural integrity of the property should be formally documented and guaranteed in writing.

Can You Still Buy a Property with Woodworm or Dry Rot?

Yes — and many buyers do. The presence of timber defects does not make a property unmortgageable. What matters to lenders is that active infestations have been professionally treated, that a treatment guarantee is in place (typically 20–30 years), and that the contractor is a recognised member of a trade body such as the Property Care Association (PCA).

If treatment has already been carried out by a previous owner, ask the seller to provide the original guarantee documentation. Some guarantees are transferable to a new owner on request — your solicitor will check this on your behalf.

What Mortgage Lenders Require

Most mortgage lenders will not release funds on a property with evidence of active woodworm or dry rot until a professional treatment has been completed, or a retention is placed on the mortgage pending completion. Your lender's mortgage valuer may flag the same issues independently — and if they do, your lender may require a specialist remediation report before proceeding to mortgage offer.

This is one reason why commissioning your own independent survey, rather than relying solely on the lender's valuation, gives you far more information at a stage when you still have options to renegotiate.

Frequently Asked Questions

Does woodworm in a survey mean I should walk away from the property?

Not necessarily. Many findings are historic rather than active and carry minimal risk. A specialist timber survey will confirm the situation and give you a treatment cost before you are committed.

How much does woodworm treatment cost in the UK?

Professional woodworm treatment for a standard property typically costs between £500 and £1,000. Structural repairs to compromised timber can add significantly to this figure depending on the extent of the damage.

Can a Level 3 survey detect all timber problems?

A Level 3 Building Survey covers accessible timber areas — roof spaces, ground floors, exposed joists and timbers — and notes evidence of woodworm, rot or decay. Areas concealed behind plasterwork may require a specialist to carry out invasive investigation.

Should I commission a separate damp and timber report?

If your survey report recommends one, yes. A specialist report typically costs between £190 and £490 and provides a treatment scope, formal quotation, and guarantee — all useful tools when negotiating with a seller or satisfying a mortgage lender.

Speak to a RICS Surveyor Before You Proceed

If you are buying a property where timber defects have been flagged, a Level 3 Building Survey from Nivek Surveying Services will give you a clear, detailed picture of the condition of all accessible timbers, with plain-English guidance on the risk level and the right next steps.

We cover Nottingham, Derby, Leicester, Coventry, Mansfield, and the wider East Midlands. Get in touch to discuss your property before you commit.