9% of privately rented homes in England had a recorded damp problem in 2023–24 — the highest rate of any housing tenure, and rising (English Housing Survey). The law covering what a landlord must actually do about it just changed its name to Awaab’s Law, after a two-year-old who died from prolonged mould exposure in a home his family had already reported. This guide explains what counts as a serious hazard, what a landlord is legally required to do and by when, and the route that lets you skip the council entirely if they don’t.
Why Damp and Mould Just Became a Legal Priority
Awaab Ishak died in December 2020, aged two, from a respiratory condition a coroner later linked to prolonged mould exposure in his family’s flat in Rochdale. His father had reported the mould to the housing association in 2017 and was told to paint over it. The case became the reason housing law changed: Awaab’s Law, which forces social landlords to investigate and fix serious hazards to a fixed timetable, came into force on 27 October 2025.
The Renters’ Rights Act 2025 extends equivalent duties to private landlords. The widely reported working date is 1 May 2026, though it’s worth being honest here rather than falsely precise: the exact structure of the private-sector timescales was still being finalised in government guidance as this was written, and it may not mirror the social-housing version detail for detail. Treat the principle — fixed, enforceable deadlines for serious hazards — as settled, and check current GOV.UK guidance for the exact private-rental timescale in force before relying on a specific number in a live dispute.
What Actually Makes Damp a “Category 1” Hazard
Not every patch of mould triggers the same legal response, and knowing the difference changes how you approach a landlord who’s dragging their feet. The Housing Health and Safety Rating System defines 29 hazards a home can have, and damp and mould growth is Hazard 1 on that list — but its severity is banded, not binary. The most serious bands, A to C, are classified Category 1; anything in bands D to J is Category 2.
The distinction is not academic. Once a council identifies a Category 1 hazard, it has a legal duty to take enforcement action — there’s no discretion involved. A Category 2 hazard gives the council the power to act if it judges the case serious enough, but nothing forces it to. A council inspector assessing black mould creeping across a bathroom ceiling with a family member who has asthma living in the room is assessing genuine health risk, not just square footage of visible growth — which is why two flats with similar-looking mould can land in different bands depending on ventilation, occupant vulnerability, and how long the problem has run.
London’s older housing stock makes this more than a theoretical distinction. A Victorian conversion in a solid-wall street in somewhere like Walthamstow or Brockley, with no cavity to insulate and original single-glazed sash windows, generates condensation far more readily than a new-build flat with modern ventilation — and condensation left unaddressed over a winter is exactly how a Category 2 patch becomes a Category 1 one. The building’s age doesn’t excuse the hazard once it’s serious; if anything, a landlord letting out solid-wall period stock without functioning extractor fans or trickle vents is choosing a property type that needs closer attention, not less.
Awaab’s Law: The Timescales That Now Apply
For social housing, already in force since October 2025, the rules are specific. An emergency hazard — hark back to Awaab’s case, black mould in a bedroom a toddler slept in — must be made safe within 24 hours of being reported. A significant but non-emergency hazard must be investigated within a fixed window, and once that investigation concludes, safety work has to start within 5 working days.
Private renters aren’t automatically covered by identical wording yet, but the direction of travel is clear and the enforcement principle — a clock starts the moment you report it, not whenever the landlord gets round to it — is what the Renters’ Rights Act is built to import into the private sector. Report the date and method of every complaint in writing, even a “leaving a landlord a note isn’t enough” comment. A dated email or portal message is the record that makes any later timescale argument, social or private, actually stick.
You Don’t Have to Wait for the Council
Council enforcement isn’t the only route, and for a private renter facing a slow or unresponsive environmental health team, it often isn’t the fastest one. The Homes (Fitness for Human Habitation) Act 2018 gives tenants a direct right to sue their landlord in the county court if the property is unfit to live in — damp and mould squarely included — without needing a council inspection or enforcement notice first.
This sits on top of a landlord’s older, more basic duty under Section 11 of the Landlord and Tenant Act 1985 to keep a property’s structure and installations in repair. The 2018 Act is the sharper tool: a successful claim can result in a court order forcing repairs, plus damages for ruined belongings, health impacts, or the distress of living with the problem. It costs money and time to bring — this is genuinely not a same-week fix — but it removes the landlord’s ability to simply wait out a slow or under-resourced council team, which is the single biggest practical advantage over the enforcement-only route.
Set expectations honestly before you start: a county court claim typically runs to months rather than weeks once you factor in pre-action correspondence, any expert survey needed to evidence the cause, and the court’s own listing backlog. Legal aid is rarely available for this specific claim type, though a no-win-no-fee arrangement with a housing disrepair solicitor is common enough that cost shouldn’t be the reason you don’t start one — most take an initial case on that basis precisely because a genuine Category 1 hazard case is usually strong on the facts.
How to Actually Report It So It Sticks
What you send matters as much as what you say. Photograph the affected area with a visible date, and keep photographing it over time so a static problem doesn’t read as a one-off. Put every report in writing — email, tenant portal, letter — rather than a phone call or a conversation on the doorstep, because a verbal complaint leaves no timestamp to hold anyone to later.
Environmental health teams and courts alike respond fastest to a clear written timeline: date first reported, date of any landlord response, what was promised, whether it happened. A single furious email eighteen months into an unresolved problem carries less weight than a dated paper trail showing you raised it early and kept raising it. If a landlord’s only response is a suggestion to “open a window more” or run a dehumidifier, treat that as a response to note down, not a fix — ventilation advice doesn’t address a structural cause like a leaking roof, failed damp-proofing, or inadequate insulation causing condensation.
What Landlords Should Be Doing Now
Waiting for the private-sector deadline to firm up before acting is the wrong read of where this is heading. A Category 1 damp or mould hazard already carries mandatory council enforcement risk under the existing HHSRS framework, regardless of Awaab’s Law’s exact private-sector rollout date, and a Homes (Fitness for Human Habitation) Act claim is already available to any tenant right now. The safer position is treating every damp or mould report as running against a fixed clock already, rather than waiting for the specific number to be confirmed.
Genuine repair costs — fixing a leak, replacing failed damp-proofing, improving ventilation — are typically deductible as revenue expenses against rental income, distinct from the capital-cost treatment that applies to a genuine improvement; our London landlord tax guide covers that distinction in full. The wider compliance picture around the Act sits in our summary of Renters’ Rights Act obligations for London landlords, and damp caused by poor insulation often overlaps directly with the issues covered in our guide to EPC rating and energy efficiency rules — a solid-wall period conversion with a poor EPC band is frequently the same flat generating a damp complaint two winters later.
What to Do Next
- Report any damp or mould in writing, with a dated photograph, the moment you notice it — not after it’s already spread.
- Ask your landlord or agent directly whether they consider it a Category 1 hazard, and keep their response in writing either way.
- If the response is advice about ventilation rather than an investigation into the cause, treat that as inadequate and escalate.
- Request an environmental health inspection from your council if the landlord doesn’t act within a reasonable time, and keep your own written timeline running in parallel.
- If council enforcement stalls, a Homes (Fitness for Human Habitation) Act claim through the county court is available without needing the council’s involvement at all — get advice from Shelter or a solicitor before filing, since it’s a real legal process, not a form you fill in and forget.
Healthier Homes, Better Lettings — FTR London
Landlords: a documented, responsive approach to damp and mould is no longer just good practice — it’s the difference between a manageable repair and a legal claim. List your property on FTR London and make your maintenance record part of what you offer prospective tenants, not something you hope never comes up.
Renters: a home with a live damp or mould problem is a home you’re entitled to see fixed, not tolerate. Browse listings on FTR London and don’t treat “a bit of condensation” as normal — check for it at viewings, and know the route above if it turns up after you’ve moved in.
