A damp and mould survey is an investigation into why a home is damp and where the mould is coming from, ending in a written report that explains the cause and what should be done about it. For landlords and letting agents it has become an essential tool: government guidance now says plainly that damp and mould is not to be blamed on tenants’ “lifestyle”, and the landlord is expected to find and fix the underlying cause. This guide explains what a proper investigation involves, what the report should tell you, and how to use it.
Why “it’s the tenant’s lifestyle” no longer works
For years, the standard response to mould in a rented home was a leaflet about opening windows. That has changed.
The government’s guidance for rented housing providers, Understanding and addressing the health risks of damp and mould in the home, was produced after the death of two-year-old Awaab Ishak in Rochdale. It says damp and mould should not be put down to tenants’ “lifestyle choices”. Cooking, showering and drying clothes are part of normal life, not optional extras. The guidance puts the responsibility on landlords to identify the underlying cause, whether that’s a building defect, inadequate ventilation or poor insulation, and to put a lasting fix in place.
This doesn’t mean occupants have no part to play. Sensible ventilation and heating help. But a landlord who answers every mould complaint with “it’s condensation, open a window” without looking at the building is now on weak ground.
What are a landlord’s legal duties on damp and mould?
The rules depend on the type of landlord:
- Social landlords (councils and housing associations) in England must meet the deadlines set by Awaab’s Law for investigating and making safe significant damp and mould hazards. We explain those timescales in Awaab’s Law explained.
- Private landlords have repairing obligations under the Landlord and Tenant Act 1985, and their properties can be assessed by the council under the Housing Health and Safety Rating System (HHSRS), the risk-based assessment introduced by the Housing Act 2004. Damp and mould is one of the hazards it covers. Where a serious hazard is found, the council can take enforcement action. The HHSRS was updated in 2026 with new operating guidance.
- Private landlords and Awaab’s Law: the Renters’ Rights Act 2025 gives the government powers to extend Awaab’s Law to private renting. The detail and the start date were still to be confirmed at the time of writing, but the direction of travel is clear.
Whichever applies to you, you’ll need to show that you found out why the home is damp and acted on it.
Do you need a “mould specialist” or a damp surveyor?
People searching for a mould specialist usually mean one of two things:
- a mould remediation contractor, who cleans and treats mould and may install ventilation; or
- someone to work out why the mould is there.
Both have their place, but they’re different jobs. Mould is a symptom. It grows where a surface stays damp, and treating the surface without dealing with the moisture means it comes back. That’s the cycle that leads to repeated complaints, repeated callouts and, for social landlords, repeated Awaab’s Law deadlines.
An independent damp surveyor is someone who diagnoses the problem but doesn’t sell the treatment. That matters because the person who decides what’s wrong then has no reason to favour one fix over another. We explain more in why use an independent damp surveyor.
What an independent damp and mould investigation covers
A proper investigation looks at the whole building, not just the patch of mould. Expect it to include:
- Your account and the tenant’s: when the problem started, when it’s worst, what’s been tried, and any history of leaks or repairs.
- Outside the building: roof coverings, gutters and downpipes, pointing and render, window and door seals, ground levels against the walls, air bricks, and signs of leaking drains.
- Inside: where the mould and damp are, their pattern and extent, and whether the damage looks like condensation, rain penetration, a leak or ground moisture.
- Ventilation: whether extractor fans are fitted, whether they actually extract, trickle vents, and whether air bricks or chimneys have been blocked.
- Heating and insulation: whether the home can be heated reasonably, cold spots, missing loft insulation and cold bridges (spots such as concrete lintels where heat escapes faster and walls stay colder).
- Measurements: surface and air temperatures, relative humidity and dew point, which together show whether condensation is likely, plus moisture readings interpreted carefully. Electrical moisture meters can mislead on masonry and salty plaster, so readings are used to compare one area with another rather than as proof on their own.
- Timbers: skirtings, floors and joists near damp areas, checked for decay.
For a step-by-step account of the visit, see what happens in a damp survey.
What should a damp report contain?
A good damp report is something you can act on and, if needed, show to someone else, whether that’s a tenant, a letting agent, a council officer or a court. It should include:
| Section | What it tells you |
|---|---|
| Scope and limitations | What was inspected, what couldn’t be accessed, and the conditions on the day |
| Findings | Room-by-room observations, with photographs and readings |
| Diagnosis | The cause or causes, in order of significance, with the reasoning |
| Recommendations | What to repair, improve or monitor, prioritised |
| Further investigation | Anything that needs opening up, monitoring or specialist input |
Look for a report that explains why it reaches a conclusion. “Rising damp, inject DPC” with no reasoning isn’t a diagnosis.
How the report supports a repair plan
The best use of a damp and mould report is to turn it into a plan with clear stages:
- Make safe: deal with any active leaks, clean mould safely, and address urgent health risks first.
- Fix the building: repair gutters, pointing, render or roof defects; correct ground levels or bridged damp proof courses; fix plumbing leaks.
- Improve ventilation and heating: fit or upgrade extraction in kitchens and bathrooms, restore blocked vents, deal with cold bridges and missing insulation.
- Advise the household: practical, respectful advice on ventilation and drying clothes, as a supplement to the repairs, not instead of them.
- Follow up: check after a few weeks and again in the colder months that the problem hasn’t returned.
This sequence also gives you a clear record of what was found, when, and what was done, which is exactly what the government guidance expects.
Letting agents: when to recommend a survey
If you manage properties, an independent survey is worth recommending when:
- mould keeps returning after cleaning;
- a tenant disputes the cause, or a landlord insists it’s “just condensation”;
- a contractor has quoted for expensive damp-proofing and the landlord wants a second opinion (see getting a second opinion on a damp-proofing quote);
- a vulnerable household is affected;
- the council or a tenant’s representative is involved.
Can tenants commission a damp survey?
Yes. Some tenants commission one where they and the landlord disagree about the cause. You’ll need access to the parts of the building being inspected, so it usually works best when the landlord agrees. If you’re a tenant and your landlord isn’t responding, your council’s private sector housing or environmental health team can inspect under the HHSRS. Social tenants should use their landlord’s repairs and complaints process first.
For practical day-to-day steps while a problem is being sorted, our guides on condensation on windows and mould in the bathroom may help.
Damp and mould in Yorkshire and the North West
A lot of rented housing across Yorkshire and Greater Manchester is older solid-walled stock: gritstone and sandstone terraces, back-to-backs and inter-war council houses. These buildings face Pennine weather, with plenty of wind-driven rain. They’re prone to cold walls, rain penetration through weathered pointing, and modern finishes such as cement render and gypsum plaster trapping moisture in walls built to breathe. Many have had kitchens and bathrooms refitted without effective extraction. A surveyor familiar with that stock is less likely to default to “rising damp” or “lifestyle”.
What does a damp and mould survey cost?
It depends on the property’s size, the number of rooms affected, access, and whether sampling or follow-up visits are needed. We don’t publish a standard price; we quote a fixed fee for the property before we book. See what affects damp survey cost for the factors involved.
Book an independent damp and mould survey
We carry out independent damp and timber surveys for private and social landlords, letting agents and tenants across West, North and South Yorkshire, Greater Manchester and nearby areas. Our surveyor is a PCA Qualified Technician in damp and timber, and as a RICS-regulated firm that sells no treatment or repairs, our report is about the cause and the right fix, nothing else. Try the damp checker for a first view, then send us the address and what’s been reported.
Sources and further reading
- Damp and mould: understanding and addressing the health risks for rented housing providers — GOV.UK
- Damp and mould in the private rented sector — GOV.UK
- Landlord and agent guide to the Housing Health and Safety Rating System (HHSRS) — GOV.UK
- Guidance document: the use of moisture meters to diagnose dampness in buildings — Property Care Association
- Investigation of moisture and its effect on traditional buildings — RICS