What does timber decay / wet rot mean on a house survey?

Wet rot is timber decay caused by sustained moisture. It does not usually spread through dry timber in the same way as dry rot, but it can seriously weaken affected joists, roof timbers, floors, or joinery if the moisture source continues. The real issue is both the damaged timber and the cause of moisture. Replacing timber without fixing leaks, ventilation, damp, or roof defects risks the same problem returning. Lenders may want evidence that structural timber is sound.

Is timber decay / wet rot a reason to pull out of a purchase?

Not automatically. Timber decay / wet rot severity ranges from cosmetic to deal-breaker. Pull out only if the cost to remediate exceeds the renegotiation headroom the seller will accept, if your lender refuses to lend on the property, or if a specialist report confirms an active, worsening defect. Most buyers renegotiate rather than walk; a written quote from a local trade is the strongest evidence to use.

How much does timber decay / wet rot cost to fix?

Costs vary widely based on severity, property type, and region. A surveyor's flagged finding usually leads to one of three outcomes: a written quote from a local trade (£0-£250 for the inspection itself), a specialist follow-up survey (£200-£600), or remediation works ranging from a few hundred pounds for cosmetic items to several thousand for structural ones. Always get two written quotes before negotiating a price reduction.

Can I get a mortgage with timber decay / wet rot?

Mortgageability depends on lender, severity, and supporting evidence. Most mainstream UK lenders will lend if a qualified specialist confirms the issue is stable, with a written report. Some apply a retention until remediation is complete; a few decline outright on certain combinations (active subsidence, knotweed without a management plan, non-standard construction). Speak to your broker before exchange, and share the surveyor's wording verbatim.

Survey finding

Timber decay or wet rot flagged in your survey

Needs attention

Wet rot is usually a moisture problem first and a timber problem second. This page explains how buyers should separate local repair from ongoing damp risk before exchange.

Last updated: 6 May 2026. Editorially reviewed: 20 May 2026.

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Common findings

Finding

Timber decay / wet rot

Needs attention

What this usually means

Wet rot is timber decay caused by sustained moisture. It does not usually spread through dry timber in the same way as dry rot, but it can seriously weaken affected joists, roof timbers, floors, or joinery if the moisture source continues.

Why it matters

The real issue is both the damaged timber and the cause of moisture. Replacing timber without fixing leaks, ventilation, damp, or roof defects risks the same problem returning. Lenders may want evidence that structural timber is sound.

Ask your surveyor

Check:Which timbers appear affected and are any structural elements involved?
Check:What moisture source do you think caused the wet rot?

Ask the seller

Check:Have any timber repairs, treatments, or damp works been carried out?
Check:Are you aware of leaks, blocked ventilation, or historic water ingress in the affected area?

Next steps

•Get a timber and damp specialist to identify both the decay and the moisture source.
•Ask for a quote that separates timber replacement from moisture-source repair.

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Specialist report needed? Yes/No with why
Should you pull out? Direct assessment

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Sources used

We use UK public and specialist sources where they are available. Public datasets can be incomplete, delayed, or missing for some addresses. Treat them as a starting point, not as a replacement for professional advice.

Source standard: preference goes to official government datasets, statutory bodies, professional standards, and primary dataset publishers. We cite the source family on the page and explain coverage limits rather than filling gaps with unsupported estimates.

Timber decay / wet rot

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