Finding mould in your flat is bad enough but when it’s coming from your neighbour’s property, things get even more complicated. Whether you’re a leaseholder, tenant, or homeowner, mould spreading from an adjacent flat can cause health issues, structural damage, and legal disputes.
This guide explains your rights under UK law and outlines the practical steps to stop the mould and hold the right party accountable.
What Causes Mould to Spread Between Flats?
In UK housing, especially older buildings or poorly insulated conversions, moisture often travels between party walls, floors, or ceilings.
Common causes of cross-property mould include:
- Leaking pipes or appliances in the neighbouring flat
- Condensation caused by poor ventilation
- Penetrating damp from shared roofs or external walls
- Structural issues like cracked render or blocked gutters
Mould thrives in humid, poorly ventilated environments, so a problem in one flat can easily migrate next door.
Is the Neighbour Responsible?
That depends on who owns what, and what caused the problem.
If your neighbour is a tenant:
- The landlord (not the tenant) is usually responsible for repairs under the Landlord and Tenant Act 1985.
- If their landlord fails to act, you may need to involve your own landlord, management company, or local council.
If your neighbour is a leaseholder:
- Responsibility may lie with the freeholder, especially if the issue originates from shared walls, roofs, or drains.
- If the problem stems from neglect (e.g. not reporting a leak), the neighbour could be directly liable.
What Are Your Legal Rights?
Under UK housing law, mould that affects health and safety is considered a statutory nuisance.
You have legal rights under:
- The Environmental Protection Act 1990
- The Housing Health and Safety Rating System (HHSRS) under the Housing Act 2004
- The Defective Premises Act 1972 (for injury or health issues)
These give you the right to:
- Demand action from the responsible party
- Report the issue to your local council’s environmental health team
- Seek compensation for health impacts or property damage in severe cases
Step-by-step: What to do
Follow these steps to document and address the mould issue:
1. Document damage
Take dated photos of:
- Visible mould and damp patches
- Condensation or water ingress
- Any health impacts (e.g. asthma, skin reactions)
Keep records of communication with neighbours, landlords, or managing agents.
2. Notify the responsible party
Start by writing to:
- Your neighbour (if appropriate)
- Their landlord or letting agent
- Your property management company or freeholder (if applicable)
Use clear, factual language and request a professional inspection.
3. Request a damp investigation
If responsibility is disputed, arrange a damp survey from a certified company.
The report may determine:
- Source of moisture
- Required repairs
- Whether legal intervention is needed
We offer expert damp surveys, call now to book yours.
4. Involve the local council
If the mould is severe or ignored, your council’s Environmental Health team can:
- Inspect the property under HHSRS
- Issue enforcement notices
Penalise negligent landlords or owners
5. Seek legal advice
If damage or health issues persist, you may need to:
- Use a housing solicitor
- Claim via small claims court or through landlord insurance
How to prevent further mould spread
While waiting for repairs or action, you can take steps to minimise risk in your own flat:
Short-term protection
- Use a dehumidifier to lower humidity
- Keep windows open where possible (ventilation)
- Avoid drying clothes indoors without extractor fans
Professional solutions
- Anti-mould treatment for walls and ceilings
- Air quality testing and purification
- Damp-proofing or insulation upgrades
Health risks of long-term exposure
Prolonged exposure to mould, especially black mould (Stachybotrys chartarum), can cause:
- Respiratory problems (asthma, wheezing)
- Allergic reactions and skin irritation
- Headaches, fatigue, and sinus infections
This is particularly dangerous for:
- Children and babies
- People with respiratory conditions
- The elderly
Conclusion
Mould caused by a neighbour’s flat is not just frustrating, it’s a genuine legal and health issue. But as a UK property resident, you have clear rights and a legal framework to support you. By documenting damage, contacting the correct parties, and seeking professional help, you can resolve the issue and restore a healthy living environment.
Need help tracing and removing mould at its source? Contact us today for expert mould removal and damp surveys.
