Dealing with damp or mould in your property?
Act promptly to meet your existing legal obligations and protect your tenants' health.
Complete step-by-step guide to preventing, identifying, and resolving damp and mould issues in rental properties. Covers your current legal obligations under the Homes (Fitness for Human Habitation) Act 2018 and HHSRS, and what to expect when Awaab's Law is extended to the PRS.
Understanding Damp & Mould
Learn the types of damp and why they occur
Identify the Type of Damp
Understanding what type of damp you're dealing with is crucial for effective treatment.
Three Main Types of Damp
There are three distinct types of damp, each with different causes and solutions:
1. Condensation (Most Common - 90% of cases)
- Cause: Warm, moist air meeting cold surfaces
- Signs: Water droplets on windows, walls, and mirrors; mould in corners and on cold walls; musty smell
- Common locations: Bathrooms, kitchens, bedrooms, behind furniture
- Season: Worse in winter when heating is on and windows are closed
2. Penetrating Damp
- Cause: Water entering through walls, roof, or windows
- Signs: Damp patches that get worse in rain; staining on walls; plaster damage; tide marks
- Common locations: Around windows, under roof line, on external walls
- Season: Worse during wet weather
3. Rising Damp (Least Common)
- Cause: Ground moisture rising through walls due to failed damp-proof course
- Signs: Tide marks up to 1 meter high; salt deposits; peeling wallpaper; damaged skirting boards
- Common locations: Ground floor walls, typically up to 1m high
- Season: Consistent year-round
⚠️ Important:
Don't assume it's rising damp - this is often misdiagnosed. 90% of damp issues are condensation-related and much easier to fix.
Checklist
- ✓Check if damp patches appear after rain (penetrating damp)
- ✓Look for condensation on windows in the morning
- ✓Check if damp is only on ground floor up to 1m (rising damp)
- ✓Note if mould appears in corners and behind furniture (condensation)
- ✓Document with photos showing location and extent
Understand Your Legal Obligations
Awaab's Law sets strict timescales for fixing damp and mould hazards.
Awaab's Law - Named After Awaab Ishak
Awaab's Law, part of the Renters Rights Act, was introduced after 2-year-old Awaab Ishak died from prolonged exposure to mould in his home. It sets strict timescales for landlords to fix health hazards.
Legal Timescales for Fixing Damp & Mould
| Hazard Level | Timescale | Example |
|---|---|---|
| Emergency | 24 hours | Severe water leak causing immediate hazard |
| Serious | 7 days | Extensive mould affecting multiple rooms |
| Other | 14 days | Localised mould in one area |
Penalties for Non-Compliance
- Fines up to £7,000 per hazard for missing deadlines
- Rent Repayment Orders - tenants can claim back up to 12 months rent
- Prohibition Orders - property cannot be let until fixed
- Criminal prosecution for serious cases
💡 Pro Tip:
The clock starts from when the tenant reports the issue. Keep detailed records of all communications and actions taken.
Don't Delay
Inspection & Assessment
Conduct a thorough property assessment
Conduct a Thorough Property Inspection
A systematic inspection helps identify all issues and their causes.
Room-by-Room Inspection Checklist
External Inspection
- Check roof for missing/damaged tiles or slates
- Inspect gutters and downpipes for blockages or damage
- Look for cracks in external walls or damaged pointing
- Check window and door seals for gaps
- Verify drainage is working and water flows away from building
- Look for overflowing gutters or water staining
Internal Inspection - Every Room
- Walls: Check for damp patches, mould, peeling paint/wallpaper
- Ceilings: Look for water stains, sagging, mould
- Windows: Check for condensation, mould on frames, broken seals
- Corners: Common mould locations, especially external walls
- Behind furniture: Move furniture to check walls behind
- Smell: Musty odours indicate hidden mould
Ventilation Check
- Test all extractor fans (should run for 15 mins after light switched off)
- Check trickle vents in windows are open and working
- Verify airbricks are not blocked
- Check bathroom and kitchen ventilation is adequate
Heating System Check
- Test heating works in all rooms
- Check radiators heat up properly
- Verify thermostat is working and accessible
- Ensure heating is affordable for tenant to run
📸 Document Everything:
Take photos of every issue, including close-ups and wide shots showing location. Date-stamp all photos. This protects you legally and helps track progress.
Templates & Downloads
Damp & Mould Inspection Checklist
Comprehensive room-by-room inspection checklist
Identify the Root Cause
Don't just treat symptoms - find and fix the underlying cause.
Common Causes and Solutions
Condensation Causes
- Inadequate heating: Property too cold, causing condensation on cold surfaces
- Poor ventilation: Moisture has nowhere to escape
- Lifestyle factors: Drying clothes indoors, not using extractor fans, keeping windows closed
- Thermal bridging: Cold spots in walls where insulation is poor
Penetrating Damp Causes
- Roof defects: Missing tiles, damaged flashing, blocked gutters
- Wall defects: Cracked render, damaged pointing, porous brickwork
- Window/door defects: Failed seals, gaps in frames
- Plumbing leaks: Hidden pipe leaks in walls or under floors
- Ground level issues: Soil piled above damp-proof course, blocked drainage
Rising Damp Causes
- Failed damp-proof course: Original DPC has broken down
- Bridged DPC: Render or soil covering the DPC
- No DPC: Older properties may not have one
⚠️ Warning:
Treating mould without fixing the cause is pointless - it will just come back. Always address the root cause first.
When to Call a Professional
If you're unsure about the cause, or suspect rising damp or serious structural issues, get a professional damp survey. This typically costs £200-£400 but can save thousands in incorrect treatments.
Fixing the Issues
Implement effective solutions
Fix Structural Issues First
Address any structural problems causing water ingress.
Priority Repairs
Roof Repairs
- Replace missing or damaged tiles/slates
- Repair or replace damaged flashing around chimneys and valleys
- Clear and repair gutters and downpipes
- Fix any roof leaks immediately
External Wall Repairs
- Repoint damaged brickwork
- Repair cracked render
- Apply water-repellent treatment to porous walls (if appropriate)
- Ensure soil and debris are below damp-proof course level
Window and Door Repairs
- Replace failed window seals
- Repair or replace damaged window frames
- Seal gaps around windows and doors
- Ensure window trickle vents are working
Drainage Improvements
- Clear blocked drains and gullies
- Ensure ground slopes away from building
- Install or repair drainage channels if needed
- Keep airbricks clear and unblocked
💡 Cost Estimates:
- Roof repairs: £200-£2,000 depending on extent
- Repointing: £30-£50 per square meter
- Window seal replacement: £50-£150 per window
- Gutter cleaning/repair: £100-£300
Improve Ventilation
Proper ventilation is crucial for preventing condensation.
Ventilation Solutions
Essential Ventilation Improvements
- Bathroom extractor fans: Must extract at least 15 litres/second and run for 15 minutes after light switched off
- Kitchen extractor fans: Must extract at least 30 litres/second (60 for cooker hoods)
- Window trickle vents: Ensure all windows have working trickle vents
- Airbricks: Check all airbricks are clear and unblocked
Advanced Ventilation Options
- Positive Input Ventilation (PIV): Whole-house ventilation system, costs £400-£800 installed
- Mechanical Ventilation with Heat Recovery (MVHR): For severe cases, costs £2,000-£5,000
- Humidity-controlled extractor fans: Turn on automatically when humidity rises
Installation Costs
- Bathroom extractor fan: £100-£250 installed
- Kitchen extractor fan: £150-£400 installed
- Window trickle vents: £20-£50 per window
- PIV system: £400-£800 installed
✅ Building Regulations:
New or replacement extractor fans must comply with Building Regulations Part F (Ventilation). Use a qualified electrician for installation.
Templates & Downloads
Ventilation Specification Guide
Technical specifications for compliant ventilation systems
Ensure Adequate Heating
Properties must be warm enough to prevent condensation.
Heating Requirements
Minimum Temperature Standards
- Living rooms: Must be capable of reaching 21°C
- Other rooms: Must be capable of reaching 18°C
- Affordability: Heating must be affordable for tenants to run
Heating System Improvements
- Upgrade old boilers: Modern condensing boilers are 90%+ efficient vs 60-70% for old boilers
- Install thermostatic radiator valves (TRVs): Allow room-by-room temperature control
- Improve insulation: Loft insulation (270mm minimum), cavity wall insulation, draught-proofing
- Consider alternative heating: Air source heat pumps, infrared panels for problem areas
Cost Estimates
- New combi boiler: £1,500-£3,000 installed
- TRVs: £30-£60 per radiator installed
- Loft insulation: £300-£500 for typical property
- Cavity wall insulation: £500-£1,500
💰 Grants Available:
Check for ECO4 scheme grants, local authority grants, and energy company obligations that may cover some or all costs of heating and insulation improvements.
Remove Existing Mould Safely
Proper mould removal protects health and prevents recurrence.
Safe Mould Removal Process
Safety First
- Wear protective equipment: gloves, goggles, face mask (FFP3 rated)
- Ventilate the area well - open windows
- Keep children and pets away during cleaning
- Don't brush or vacuum mould - this spreads spores
Cleaning Method
- Prepare solution: Mix specialist mould remover or diluted bleach (1 part bleach to 4 parts water)
- Apply to affected areas: Spray or wipe onto mouldy surfaces
- Leave for 15-20 minutes: Allow solution to work
- Wipe clean: Use disposable cloths, dispose of immediately
- Dry thoroughly: Use dehumidifier or heater to dry area
- Apply mould-resistant paint: Once dry, paint with anti-mould paint
When to Call Professionals
- Mould covers more than 1 square meter
- Mould has penetrated into plaster or wood
- Mould returns quickly after cleaning
- Black mould (Stachybotrys) is present
- Tenant has health issues affected by mould
⚠️ Important:
Cleaning mould is only a temporary fix. You MUST address the underlying cause (ventilation, heating, water ingress) or it will return.
Professional Mould Remediation Costs
- Small area (under 1m²): £200-£400
- Medium area (1-3m²): £400-£800
- Large area (3m²+): £800-£2,000+
- Severe cases requiring replastering: £2,000-£5,000+
Health Hazard
Prevention & Tenant Education
Prevent future issues through education
Educate Tenants on Condensation Prevention
Tenant behaviour significantly affects condensation levels.
Tenant Guidance - Preventing Condensation
Daily Actions
- Open windows: Open windows for 10-15 minutes each morning to let moisture escape
- Use extractor fans: Always use when cooking or showering, leave running for 15 minutes after
- Keep trickle vents open: Small vents in windows should stay open year-round
- Wipe condensation: Wipe down windows and sills each morning
Heating Advice
- Keep heating on low constantly: Better than high heat intermittently (e.g., 18°C all day vs 22°C for 2 hours)
- Heat all rooms: Don't close off unused rooms - this creates cold spots
- Use thermostatic controls: Set radiator valves to maintain consistent temperature
Drying Clothes
- Dry outside: Whenever possible, dry clothes outside
- Use a vented dryer: If using a tumble dryer, ensure it vents outside
- If drying inside: Open windows, close door to rest of house, use dehumidifier
Furniture Placement
- Leave gaps: Keep furniture 5-10cm away from external walls
- Don't block vents: Never block airbricks or extractor fans
- Allow air circulation: Don't overfill wardrobes or cupboards
📄 Provide Written Guidance:
Give tenants a written condensation prevention guide at move-in and when issues arise. This protects you legally and helps tenants understand their role.
Templates & Downloads
Tenant Condensation Prevention Guide
Information sheet for tenants on preventing condensation
Implement Ongoing Monitoring
Regular checks prevent small issues becoming big problems.
Ongoing Monitoring Plan
Regular Property Inspections
- Quarterly inspections: Check for early signs of damp or mould
- Post-winter inspection: Thorough check after winter when condensation is worst
- After heavy rain: Check for penetrating damp after prolonged wet weather
What to Check
- Windows for condensation and mould
- Corners of rooms, especially external walls
- Behind furniture (ask tenant to move items)
- Bathrooms and kitchens for mould
- Extractor fans still working
- Heating system functioning properly
- External: gutters, roof, walls
Tenant Reporting
- Encourage tenants to report issues early
- Provide clear contact details for maintenance
- Respond to reports within 24 hours
- Keep records of all reports and actions taken
Seasonal Maintenance
- Autumn: Clear gutters, check roof, service heating
- Winter: Monitor for condensation issues
- Spring: Check for winter damage, clean extractor fans
- Summer: Major repairs and improvements
💡 Pro Tip:
Use a property management app or spreadsheet to track inspections, maintenance, and tenant reports. This creates an audit trail for legal protection.
Checklist
- ✓Schedule quarterly property inspections
- ✓Create inspection checklist
- ✓Set up tenant reporting system
- ✓Plan seasonal maintenance tasks
- ✓Keep detailed records of all checks
- ✓Respond to tenant reports within 24 hours
- ✓Document all remedial work with photos
Frequently Asked Questions
Common questions about damp & mould management
What's Next?
You've completed the Damp & Mould Management. Here are some related resources to help you further.
Guidance only. Landlord Handbook provides practical information to help landlords understand their responsibilities. It is not legal or financial advice. Always check the latest GOV.UK guidance and seek professional advice where appropriate.