Damp and mould in rented homes: fix the cause
Government guidance is clear that landlords must find and fix the underlying cause of damp and mould, not just wipe it off. Here is how to work out the cause, what fixes it, and how to handle a tenant's report.
Published 11 November 2026 · By Positive Contractors, NICEIC Approved Contractor and Gas Safe registered
What the guidance says
The government's guidance Understanding and addressing the health risks of damp and mould in the home (updated August 2024) applies to social and private landlords in England. Its key points:
- Damp and mould affect health, mainly the airways and lungs, and some people are at much higher risk
- Landlords should respond with urgency and treat reports seriously
- The underlying cause must be found and tackled: building defects, poor ventilation, or condensation. Removing surface mould on its own will not stop it coming back
- Tenants should not be blamed for everyday living such as cooking, showering and drying clothes
- The home should be inspected again after the work, the guidance suggests at least 6 weeks later, to check the problem has gone
Damp and mould is also one of the hazards councils assess under the Housing Health and Safety Rating System, and they can require a landlord to fix it.
Find the cause first
| Type | Typical signs and causes |
|---|---|
| Condensation | Black spotty mould in corners, behind furniture, around windows and on cold walls, worst in winter. Moist air from cooking, bathing and drying clothes meets cold surfaces, with too little extraction or heating to clear it. |
| Penetrating damp | Patches that grow after rain, often on one wall. Leaking gutters and downpipes, cracked render, failed pointing, roof or flashing defects, or window seals. |
| Leaks | Stains below bathrooms and kitchens, or around pipes, that appear whatever the weather. Failed seals, waste pipes or supply pipes. |
| Rising damp | A tide mark up to about a metre above the floor on ground floor walls, sometimes with salts. Often caused by bridged or failed damp proof courses, or raised ground levels outside. |
What fixes it
- Extraction: a working extractor fan in every kitchen and bathroom, ideally humidity-controlled or continuous-running so it works without the tenant remembering
- Whole-house ventilation: positive input ventilation in a loft, or MVHR in well-sealed or refurbished homes, where condensation keeps coming back
- Heating: a heating system that works and that the tenant can afford to run, so walls stay above the dew point
- Repairs to the building: gutters, downpipes, pointing, roof and window seals for penetrating damp; pipework and seals for leaks
- Mould removal: treat and clean affected areas once the cause is fixed, and redecorate with mould-resistant paint where it helps
Telling a tenant to open windows can help, but the guidance says advice to tenants must never replace dealing with the cause.
Handling a tenant's report
- Acknowledge it quickly, and ask for photos and where the damp is
- Inspect promptly, and sooner if anyone in the home is vulnerable
- Write down the likely cause and the work you will do, with dates
- Do the work, then clean and treat the mould
- Re-inspect several weeks later and keep a dated record of everything
In social housing, Awaab's Law already sets fixed deadlines for investigating and repairing damp and mould. The Renters' Rights Act allows it to be extended to private renting, but no start date has been set. See our Renters' Rights Act guide.
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Common questions
Is condensation mould the tenant's fault?
Not by default. The government guidance says tenants should not be blamed for everyday living. Landlords are expected to provide adequate ventilation and heating so normal cooking, bathing and drying clothes don't cause mould.
Will a new extractor fan stop the mould?
If condensation is the cause, a properly sized fan that runs automatically usually makes a big difference. Persistent cases may need whole-house ventilation such as positive input ventilation or MVHR.
How soon should a landlord act on damp and mould?
The guidance says to respond with urgency, and faster where someone in the home is vulnerable. Keep a dated record of the report, the inspection and the work.
Do you deal with damp and mould for landlords?
Yes. We investigate the cause, fit extraction and ventilation, repair leaks and the building fabric, and treat and redecorate affected areas across London and Essex.
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