Wet Rot Diagnosis & Treatment Across London & Surrey
Identify, treat and repair wet rot before it becomes a structural problem.
What is Wet Rot?
Wet rot is a broad term for several species of wood-decaying fungus that attack timber with consistently high moisture content — typically above 50% moisture content by weight. The most common wet rot fungi are Coniophora puteana (cellar fungus) and Fibroporia vaillantii, but the practical treatment approach is the same regardless of species.
Unlike dry rot, wet rot does not have the ability to spread through masonry or travel beyond the area of wetness. However, it will continue to attack timber as long as moisture is present, and in structural timber — floor joists, rafters, lintels — the consequences can be severe.
Common Locations for Wet Rot
- ✓Window frames and sills — particularly timber sills where paint protection has failed and water has been sitting in joints
- ✓External door frames — the bottom sections of door frames and cills are vulnerable due to ground splash and condensation
- ✓Roof timbers — rafters, battens and sarking boards affected by roof leaks or inadequate ventilation
- ✓Floor joists — in suspended timber floors, particularly near external walls where the DPC has failed or airbricks are blocked
- ✓Skirting boards and architraves — where damp walls are in contact with timber
- ✓Structural lintels — in older properties, timber lintels above openings affected by penetrating damp
- ✓Decking and outbuildings — external timber structures with inadequate protection or drainage
How We Treat Wet Rot
Survey & Assessment
We survey all affected timber using moisture meters and probes to determine the extent of decay. We assess structural integrity and identify the moisture source.
Moisture Source Fix
Treating wet rot without fixing the moisture source is pointless — the rot will return. We identify and repair the underlying moisture problem as part of the treatment.
Fungicidal Treatment
Remaining sound timber in the vicinity of decay is treated with preservative fungicide by brush, spray or injection to kill residual fungal growth and protect against re-infection.
Timber Replacement
Decayed timber is cut out and replaced with pre-treated structural timber, matched to the existing section where possible. End-grain of new timber is treated with preservative.
Preservative Consolidants
In non-structural applications (window frames, decorative timber), decayed material can sometimes be consolidated and rebuilt using epoxy-based wood hardeners and fillers rather than full replacement.
Guarantee
All wet rot treatments are guaranteed. The guarantee period covers both the fungicidal treatment and any structural repairs carried out by our team.
How do I know if my window frames have wet rot?
Common signs include: softness when pressed, paint bubbling or flaking, discolouration (darkening) of the timber, visible cracking, and a spongy or fibrous texture when probed. Our survey will confirm if rot is present and assess its extent.
Is wet rot structurally dangerous?
Wet rot in structural timber — floor joists, rafters, lintels — can compromise structural integrity if it progresses unchecked. Early treatment prevents the need for major structural works.
Can wet rot spread to dry areas?
Unlike dry rot, wet rot cannot spread beyond the areas of wetness. However, if the moisture source is not addressed, the wet area can expand, and the rot will spread with it.
Ready to Get Started?
Surveys available across London and Surrey. Same-day attendance available.
Frequently Asked Questions
How quickly can you attend in this area?
We aim to attend damp, mould and leak inspections within 2–5 working days. For urgent situations — active water ingress, mould affecting health, or pre-sale requirements — we offer same-day and next-day emergency attendance. Call 0800 054 1524 to check availability.
What types of damp do you treat here?
We treat all types of damp: rising damp (ground moisture rising through walls), penetrating damp (moisture entering through external walls or roof), condensation damp (from poor ventilation), and leak-related damp from plumbing or drainage failures. Every survey identifies the root cause before treatment is recommended.
Are your reports accepted by insurers and solicitors?
Yes. All our damp surveys, mould inspections and leak detection reports are written in a format accepted by all major UK insurers (Aviva, AXA, Direct Line, LV, Zurich) and by solicitors for property disputes and conveyancing. Reports are signed by a qualified inspector with full photographic evidence.
Do you provide Awaab’s Law compliant reports for landlords?
Yes. We provide Awaab’s Law compliant investigation and remediation reports for landlords and housing associations across our coverage area. Under the Social Housing Regulation Act 2023, social landlords must investigate and act on damp and mould within strict timeframes. Our reports document every stage of the inspection and treatment process.
What is the typical cost of a damp survey?
A professional damp survey typically costs £150–£350 depending on property size and complexity. This includes a full written report with moisture readings and photographic evidence. Call 0800 054 1524 for a quote specific to your property.