Damp and mould are among the most common issues in rented homes — and also one of the most misunderstood. Left unresolved, they can damage the property, affect tenant health, and lead to disputes about responsibility.

The good news is that most problems can be prevented or resolved quickly when both landlords and tenants understand their roles and legal obligations.

Condensation is the most common cause in rented homes, but penetrating damp, leaks, or insulation problems can also be responsible.

Why it matters

Damp and mould are not just cosmetic issues. They can:

• Damage walls, ceilings, carpets and furnishings

• Cause unpleasant odours

• Lead to timber decay and long-term structural problems

• Trigger respiratory issues, especially for children or vulnerable occupants.

That’s why both landlords and tenants have a duty to act early.

Landlord responsibilities

Landlords must ensure the property is structurally sound, safe and properly maintained.

This typically includes:

Maintaining the structure of the property

• Roof, walls, windows and gutters in good repair

• No leaks or penetrating damp

• Adequate insulation where required

Keeping installations in working order

• Heating systems must function properly

• Extractor fans should work in kitchens and bathrooms

• Plumbing must not leak

Investigating reported problems promptly
If a tenant reports damp, landlords should:

• Inspect quickly

• Identify the cause

• Arrange repairs where needed

If mould results from a building defect, the responsibility sits with the landlord.

Tenant responsibilities

Tenants also play a key role in preventing condensation-related mould.  They should:

Ventilate the property

• Open windows regularly

• Use extractor fans when cooking or showering

• Keep trickle vents open where fitted

Heat the home reasonably - A consistently cold property increases condensation risk.

Reduce moisture build-up

• Avoid drying clothes on radiators without ventilation

• Keep lids on pans when cooking

• Wipe condensation from windows and sills

Report problems early - Small issues become large ones when ignored. Tenants should notify the landlord or agent as soon as damp appears.

Legal responsibilities around damp and mould in rented homes

Damp and mould are not just maintenance issues — they can be considered legal housing hazards if not addressed properly. UK legislation places clear obligations on landlords to ensure rented properties are safe and fit for occupation.

Fitness for Human Habitation

Under the Homes (Fitness for Human Habitation) Act 2018, rental properties must be fit to live in at the start of the tenancy and throughout it.  A property may be considered unfit if serious damp or mould is present.  Tenants have the right to take legal action if the landlord fails to resolve hazards within a reasonable time after being notified.

Housing Health and Safety Rating System (HHSRS)

Local authorities assess housing conditions using the Housing Health and Safety Rating System.  Damp and mould fall under the category of excess cold and damp hazards.  If a council identifies a serious risk, they can:

• Require the landlord to carry out repairs

• Serve an Improvement Notice

• Carry out emergency remedial action

• In extreme cases, restrict use of the property

Repair obligations in law

Section 11 of the Landlord and Tenant Act 1985 requires landlords to:

• Keep the structure and exterior in repair

• Maintain heating and hot water systems

• Repair pipework, drains and ventilation systems

If damp is caused by roof leaks, plumbing faults, structural defects, or failed ventilation systems, the landlord is legally responsible for fixing the issue.

Tenant responsibilities in law

Tenants must:

• Use the property in a “tenant-like manner”

• Ventilate and heat the property reasonably

• Report problems promptly

If mould occurs mainly due to lifestyle factors (for example persistent lack of ventilation), responsibility may be shared — but landlords must still investigate before reaching any conclusion.

A growing focus on mould prevention

Recent housing guidance and enforcement trends make it clear that damp and mould complaints should never be ignored. The expectation is that landlords act early, investigate properly, and prioritise building performance before assuming lifestyle causes.

In short, the direction of travel in housing law is towards prevention, documentation and prompt action.

Download our Landlord Damp & Mould Guide

To help you prevent issues before they start, we’ve produced a free guide covering:

• How to identify the type of damp

• What landlords must legally repair

• What tenants should do day-to-day

• Simple prevention tips that really work

• When professional treatment is needed

• How to stay compliant and avoid disputes

Download your free copy today - you can find this in our Free Resources tab.