Damp & Mould Landlord Responsibilities London 2026

London landlords are legally responsible for fixing damp and mould caused by disrepair or building defects, and painting over it is not a fix. Under the Homes (Fitness for Human Habitation) Act 2018 a rented home must be free from serious damp and mould hazards throughout the tenancy, and a council can act under the Housing Health and Safety Rating System where mould reaches a Category 1 hazard. Awaab's Law, which sets strict timescales to investigate and repair damp and mould, currently applies to social housing and is expected to be extended to the private rented sector. This guide explains your duties and how the cause is traced and fixed.

What are a landlord's legal responsibilities for damp and mould?

A landlord's core duty is to keep the structure and exterior of the property in repair and to ensure the home is fit for human habitation, and damp and mould caused by disrepair fall squarely within that. The Homes (Fitness for Human Habitation) Act 2018 implies a term into almost every tenancy that the property must be fit for human habitation at the start of and throughout the tenancy. Where serious damp and mould make the home unfit, the tenant can take the landlord to court directly, without involving the council, and seek an order for the works to be done plus compensation. The Landlord and Tenant Act 1985 (section 11) separately requires landlords to keep the structure, exterior, and installations for water, heating and sanitation in repair, which covers the leaks, failed pointing and broken gutters that cause most penetrating damp. The practical point is that responsibility follows the cause. Where damp and mould arise from a building defect, a leak, or a lack of adequate ventilation that the landlord could remedy, it is the landlord's job to put right. Telling a tenant to simply wipe down the mould or open more windows is not a lawful discharge of that duty where the underlying cause is a defect in the property. Landlords letting in London can read more about their obligations on our /for-landlords page.

The Housing Health and Safety Rating System and Category 1 hazards

Beyond the tenant's own right to act, local councils have power to intervene where damp and mould become a health hazard, and the tool they use is the Housing Health and Safety Rating System (HHSRS). Under the HHSRS, an environmental health officer assesses hazards in a property and scores them. Damp and mould growth is one of the 29 recognised hazard categories. Hazards are rated as either Category 1 (the most serious) or Category 2. Where a council finds a Category 1 damp and mould hazard, it has a duty to take enforcement action, which can include serving an improvement notice requiring the landlord to carry out remedial works by a deadline, a prohibition order restricting use of part of the property, or in serious cases emergency remedial action carried out by the council and recharged to the landlord. Ignoring an improvement notice is a criminal offence and can lead to prosecution, an unlimited fine, or a civil penalty of up to £30,000 per breach imposed by the council instead of prosecution. A formal notice also makes the landlord vulnerable to a rent repayment order. The message is straightforward: once a council is involved over Category 1 damp and mould, the cost and consequences of inaction rise sharply, and carrying out a proper repair promptly is always the cheaper course.

Awaab's Law and the move toward the private rented sector

The most significant recent development is Awaab's Law, named after Awaab Ishak, the two-year-old who died in 2020 from prolonged exposure to mould in a social home, and landlords need to understand both what it does now and where it is heading. Awaab's Law was introduced through the Social Housing (Regulation) Act 2023 and currently applies to social housing in England. It works by setting legally binding timescales: registered social landlords must investigate reported damp and mould hazards within a fixed period and begin repairs within a further fixed period, with emergency hazards addressed much faster. The aim is to remove the delay and dismissiveness that allowed Awaab's mould to go untreated. Crucially for private landlords, the Government's wider rental reform agenda, carried through the Renters' Rights legislation, is expected to extend Awaab's Law principles to the private rented sector, applying similar duties to investigate and fix damp and mould within set timescales. This extension is proposed and being implemented through secondary legislation rather than already in force for private lets, so the exact timescales and start dates for private landlords are still being confirmed. The sensible position is to operate now as though strict timescales already apply: respond to a damp or mould report promptly, investigate the cause, and carry out the repair without delay. Landlords who already work this way will face no adjustment when the rules bite.

Why painting over mould fails: fixing the root cause

The single most common mistake landlords make is treating the surface and ignoring the source, and it never works for long because mould is a symptom, not the disease. Mould grows where surfaces stay damp, so the only durable fix is to remove the source of moisture. Painting over mould, even with mould-resistant paint, hides it for a few weeks before it bleeds back through, because the wall behind is still wet. Anti-mould washes kill the visible growth but do nothing about why the wall is damp. A genuine repair starts with a diagnosis: is this penetrating damp from a defect letting water in, rising damp from a failed or bridged damp-proof course, condensation from inadequate ventilation, or the after-effect of a leak? Each cause has a different fix. Penetrating damp is solved by repairing the defect, repointing, fixing the roof or gutters, sealing around windows. Rising damp needs the damp-proof course addressed and any bridging removed. Condensation is solved by improving ventilation and heating, not by lecturing the tenant. A leak needs the leak found and stopped before anything else. Only once the source is dealt with does it make sense to strip back, treat, replaster and redecorate the affected area. We approach damp and mould this way through our leak damage repair and property repairs services, because reinstating a wall over a source that is still active simply books the same job in again next winter.

Damp type	Typical cause	The real fix
Penetrating damp	Defect letting water in: roof, gutter, pointing, window seal	Repair the external defect, then dry and reinstate internally
Rising damp	Failed or bridged damp-proof course	Address the DPC and remove bridging, replaster with appropriate system
Condensation damp	Poor ventilation and heating, moisture-laden air	Improve extraction and ventilation, treat cold spots, then redecorate
Leak-related damp	Plumbing leak, overflow or escape of water	Trace and stop the leak, dry the structure, then repair finishes

How tenants report damp and mould, and what landlords must do

A landlord's clock effectively starts when a tenant reports a problem, so how reports are handled matters as much as the repair itself. Tenants should report damp and mould to the landlord or managing agent in writing, with photographs and the date noticed, and keep a record. If the landlord does not respond, the tenant can escalate to the local council's environmental health team, who can inspect under the HHSRS. Under the Fitness for Human Habitation Act the tenant can also pursue the landlord directly through the courts. A documented report that goes unanswered is precisely the evidence that supports enforcement, compensation, or a rent repayment order against the landlord. For the landlord, the correct response to any damp or mould report is consistent: acknowledge it quickly, arrange an inspection to diagnose the cause rather than assume it, carry out the remedial works needed to remove the source, and keep records of what was found and done. Treating reports seriously and acting promptly is not only good practice, it is the behaviour that the forthcoming private-sector timescales are designed to enforce. Landlords who dismiss damp as the tenant's lifestyle, without investigating whether a defect is responsible, are the ones who end up facing notices and claims.

How we trace the source and reinstate the property

Fixing damp and mould properly is a sequence, and skipping a step is what leaves landlords paying twice, so it helps to understand how a thorough repair is carried out. The work begins with a survey to identify the cause. That can mean inspecting the roof, gutters, pointing and window seals for penetrating damp, checking the damp-proof course, assessing ventilation and identifying cold spots that drive condensation, and using moisture readings and, where a leak is suspected, leak detection to find the source. Diagnosis first means the repair targets the actual problem rather than the visible symptom. Once the source is identified, it is dealt with: the external defect repaired, the leak stopped, ventilation improved, or the damp-proof course addressed. Only then does reinstatement begin, allowing the structure to dry, treating the affected area, replastering where the plaster has blown or is salt-contaminated, and redecorating so the finish matches. Done in this order, the repair holds, because the wall is dry before it is covered. This is the approach we take on damp and mould work across London, combining leak detection, structural repair and reinstatement so that landlords get a fix that lasts rather than a cosmetic patch that reappears. Getting it right once protects the tenant's health, the landlord's compliance position, and the fabric of the building.

Frequently Asked Questions

Is a landlord legally responsible for damp and mould?

Yes, where the damp and mould are caused by disrepair or a building defect. The Homes (Fitness for Human Habitation) Act 2018 requires the property to be fit for human habitation throughout the tenancy, and section 11 of the Landlord and Tenant Act 1985 requires the landlord to keep the structure, exterior and water, heating and sanitation installations in repair. Telling a tenant to simply wipe down mould caused by a defect is not a lawful discharge of that duty.

What is Awaab's Law and does it apply to private landlords?

Awaab's Law was introduced through the Social Housing (Regulation) Act 2023 and sets legally binding timescales to investigate and fix damp and mould. It currently applies to social housing. Extending it to the private rented sector is proposed under the Renters' Rights agenda and is being implemented through secondary legislation, so exact timescales and start dates for private landlords are still being confirmed. Private landlords should already respond to damp and mould reports promptly and fix the cause.

Can the council take action over mould in a rented property?

Yes. Councils assess hazards under the Housing Health and Safety Rating System (HHSRS), where damp and mould growth is a recognised hazard. A Category 1 hazard triggers a duty to act, and the council can serve an improvement notice, a prohibition order, or carry out emergency works. Ignoring an improvement notice is a criminal offence and can lead to a fine or a civil penalty of up to £30,000, plus exposure to a rent repayment order.

Why does painting over mould not work?

Because mould is a symptom of a damp surface, not the cause. Painting over it, even with mould-resistant paint, hides it for a few weeks before it bleeds back through, since the wall behind is still wet. The only durable fix is to remove the source of moisture, whether that is penetrating damp, rising damp, condensation or a leak, then dry and reinstate the affected area.

How quickly must a landlord deal with reported damp and mould?

Once Awaab's Law is extended to private lets, fixed timescales are expected to apply, requiring landlords to investigate a reported hazard within a set period and begin repairs within a further set period, with emergencies handled faster. Those timescales are still being confirmed for the private sector, so the safe approach now is to acknowledge a report immediately, inspect to diagnose the cause, and carry out the repair without delay.

Damp and Mould: Landlord Responsibilities in London (2026)