Damp & Mould Inspection Checklist for Properties

Damp and mould are among the most common and damaging issues found in residential properties across the United Kingdom. Left unchecked, damp causes structural deterioration, destroys fixtures and finishes, and creates conditions for mould growth that can seriously affect the health of occupants. Recent legislation has strengthened the obligations on landlords and property owners to address damp and mould promptly. This checklist provides a systematic approach to inspecting properties for damp and mould, identifying the causes, and documenting findings for remediation.

Why Damp and Mould Inspections Matter

Damp and mould affect an estimated one in five homes in the UK. The health consequences are well documented: prolonged exposure to mould spores can cause respiratory problems, allergic reactions, and exacerbate conditions such as asthma and eczema. For vulnerable occupants including children, elderly residents, and those with compromised immune systems, the risks are even greater. From a property perspective, damp causes timber decay, plaster deterioration, and corrosion of metal components. For landlords, Awaab's Law now imposes strict timescales for investigating and addressing damp and mould complaints. A proactive inspection regime demonstrates compliance, protects tenants, and prevents small problems from becoming major remediation projects.

The Damp and Mould Inspection Checklist

Visual Indicators of Damp

A thorough visual inspection is the first step in identifying damp problems. Many signs of damp are visible on wall and ceiling surfaces if you know what to look for and inspect systematically.

• Check all walls at ground floor level for tide marks, staining, or salt crystallisation indicating rising damp
• Inspect walls below windows and around door frames for water staining from penetrating damp
• Look for bubbling or peeling paint and wallpaper which often indicates moisture beneath the surface
• Examine ceilings for brown staining or damp patches that could indicate a leak from above
• Check skirting boards and floor edges for warping, softness, or discolouration from moisture

Mould Growth Assessment

Mould requires moisture to grow and typically appears first in areas with poor ventilation and high humidity. Identifying mould early and understanding its extent is essential for effective remediation.

• Inspect corners of rooms, particularly at ceiling level, for black, green, or white mould growth
• Check behind furniture placed against external walls where airflow is restricted
• Examine window reveals, frames, and sills for condensation mould
• Look inside wardrobes and cupboards on external walls for musty smells or visible mould
• Inspect bathroom ceilings, tile grout, and silicone seals for persistent mould growth

Condensation Assessment

Condensation is the most common cause of damp in UK homes. It occurs when warm, moist air contacts cold surfaces, depositing water that creates ideal conditions for mould growth.

• Check windows for excessive condensation, particularly in the morning, which indicates poor ventilation
• Inspect window trickle vents to confirm they are present, open, and unobstructed
• Assess extractor fans in kitchens and bathrooms for correct operation and adequate extraction rate
• Look for condensation on cold water pipes, cold external walls, and behind headboards

Rising Damp Investigation

Rising damp occurs when groundwater is drawn up through masonry by capillary action. A functioning damp-proof course should prevent this, but defects, bridging, or absence of a DPC can allow moisture to rise.

• Check the external damp-proof course is visible and not bridged by raised ground levels, render, or debris
• Measure the height of any internal damp staining — rising damp typically reaches up to one metre
• Look for white salt deposits on internal wall surfaces which indicate mineral salts carried by rising moisture
• Inspect the base of internal walls for crumbling plaster or deteriorating pointing at ground level

Penetrating Damp Investigation

Penetrating damp enters through the building envelope due to defects in the roof, walls, windows, or plumbing. Identifying the entry point is critical for effective repair.

• Trace damp patches to their highest point to identify the likely entry route
• Inspect external walls directly above internal damp for cracks, failed pointing, or damaged render
• Check window and door seals for gaps that could allow wind-driven rain to penetrate
• Examine the roof above any damp area for missing tiles, failed flashing, or blocked gutters
• Investigate whether internal plumbing leaks could be the source rather than external penetration

Subfloor and Below-Ground Assessment

Ground floor rooms with suspended timber floors or solid floors can be affected by moisture from below. Inadequate ventilation below suspended floors leads to timber decay and damp conditions.

• Check airbricks around the property perimeter are clear and providing ventilation to the subfloor void
• Inspect accessible subfloor areas for standing water, excessive moisture, or timber decay
• Look for damp-proof membrane failures on solid floors indicated by damp patches on the surface
• Verify that external ground levels are below the internal floor level and the damp-proof course

Ventilation and Airflow Assessment

Adequate ventilation is the primary defence against condensation damp. Modern properties with sealed windows and draught-proofing can inadvertently reduce airflow to problematic levels.

• Test all extractor fans for correct operation and adequate extraction rates using a tissue test
• Check that trickle vents are fitted to all habitable rooms and that occupants understand their purpose
• Assess whether any rooms lack any form of background ventilation which could contribute to damp
• Verify that tumble dryers are vented externally and not discharging moisture into the property

Moisture Readings and Documentation

While professional damp surveys use calibrated instruments, a handheld moisture meter provides useful indicative readings that help quantify and track damp conditions over time.

• Take moisture meter readings on all walls at regular intervals and record the values with locations
• Compare readings between internal and external walls to identify patterns
• Document readings at different heights on affected walls to distinguish between rising and penetrating damp
• Record ambient temperature and relative humidity in affected rooms for reference

Best Practices for Damp and Mould Inspections

• Inspect during or shortly after wet weather when damp problems are most visible
• Move furniture away from external walls before inspecting to reveal hidden damp and mould
• Use a moisture meter for objective measurements rather than relying solely on visual assessment
• Photograph all damp and mould with date stamps and measure the affected area for records
• Distinguish between symptoms and causes — treating mould without addressing the moisture source is ineffective
• For rental properties, respond to tenant reports promptly and document all investigations and actions taken

How Checksheets Helps

Checksheets provides a comprehensive digital inspection tool specifically designed for damp and mould assessments. Follow the structured checklist room by room, recording moisture readings, photographing affected areas, and categorising issues by type and severity. The platform helps you distinguish between condensation, rising damp, and penetrating damp with guided assessment criteria. Generate professional reports that document your findings and recommended actions, suitable for sharing with tenants, contractors, or housing authorities. For landlords responding to damp complaints, Checksheets creates a timestamped audit trail that demonstrates compliance with Awaab's Law timescales. Track remediation progress through follow-up inspections and confirm that repairs have resolved the underlying issues.

Damp and mould are problems that worsen when ignored. A proactive inspection approach protects occupant health, preserves your property, and keeps you on the right side of your legal obligations. Start your free checklist today and address damp and mould with confidence and professionalism.