Preparing Your Home for Winter Damp Issues
London property owners should always be on the lookout for damp and mould, which can attack any property, old or new. The winter is, of course, a season when dampness is more prevalent and in this short blog, we offer a few tips on how to prepare your London home for winter damp issues.
- Ventilation – Every property should be well ventilated, especially during the damp winter months; open windows regularly and keep kitchen and bathroom doors closed when condensation levels are high. If there are rooms that you don’t normally heat, turn on the radiators for a few hours 2-3 times a week, which will remove moisture in the air. Mechanical ventilation can be used with natural ventilation to create an airflow and this will greatly reduce damp and condensation.
- Penetrating damp – We haven’t seen the Sun for months here in the UK, which doesn’t help with damp and moisture and prior to the arrival of winter, you should carry out a thorough inspection of all exterior and interior walls, ceiling and floors. If you prefer, we at London Damp Specialists can carry out penetrating damp solutions that come with a quote for any necessary remedial work. We can match any survey quote and our work had a gold seal guarantee for a full 30 years.
- Condensation – It is perfectly normal for an occupied building to generate condensation, hot water and cooking adds a lot of moisture to the air; ventilation is the key. Open a few windows to create a good airflow, 30 minutes is enough to dry out the air, do this twice a week if possible and this will remove most of the moisture from the interior. If your windows have condensation issues, use a dry cloth to remove the water and do this whenever you see water. If you would prefer a professional approach, we at London Damp Specialists offer complete condensation solutions and we guarantee our work for 30 years.
- Roof inspection – Blocked guttering causes rainwater to cascade down the exterior walls, while missing roof tiles let rain into the roof structure and can damage joists and rafters. You should have your roof inspected by a local roofer; it can be dangerous to climb on a roof, especially if you are not familiar with working at height. This is not something you should overlook, a common source of moisture and damp is the roof, so make sure you ask a local roofing contractor to add you to their list of roof inspections.
- Rising damp – Your property should have a DPC membrane that prevents moisture rising into the building. The course is made from bitumen and should it be worn down or damaged, it can no longer do what it is designed to. We can carry out a thorough DPC inspection to ensure that all is well.
As soon as the summer starts to turn into autumn, this is the ideal time to call London Damp Specialists on 020 8528 3864 or fill in the form on your website and book a comprehensive damp survey.
Professional Damp Diagnostic Equipment
Electronic Moisture Meter
Purpose:
Takes comparative moisture readings from accessible walls, floors, ceilings and other surfaces to identify abnormal moisture patterns.
Common Uses / Notes:
Helps the surveyor map affected areas and identify patterns associated with rising damp, penetrating moisture, condensation and potential leaks. Readings support the survey but are not a diagnosis on their own.
Deep-Reading Moisture Meter
Purpose:
Investigates below the immediate surface of building materials without requiring extensive removal of finishes.
Common Uses / Notes:
Helps locate moisture within walls, beneath accessible floors, inside subfloor areas and deeper within the building fabric where hidden moisture is suspected.
Non-Destructive Moisture Scanner
Purpose:
Checks for changes in moisture beneath walls, ceilings and flooring non-invasively without puncturing or damaging the finished surface.
Common Uses / Notes:
Ideal for decorated walls, ceilings and flooring where pin testing would be undesirable. Useful for tracing water migration paths and comparing dry areas against suspected damp sections.
High-Definition Borescope Camera
Purpose:
Provides a close visual inspection of concealed or difficult-to-access spaces without opening up large sections of the building.
Common Uses / Notes:
Used beneath floors, inside wall cavities, behind linings and around hidden pipework to uncover leaks, hidden moisture, timber decay, or construction defects with minimal disturbance.
4K Aerial Drone
Purpose:
Captures high-resolution images of roofs, chimney stacks and other inaccessible high-level external areas.
Common Uses / Notes:
Inspects roof coverings, chimney stacks, flashing, guttering, parapet walls, valleys, high-level brickwork and difficult elevations to reveal defects linked to penetrating damp and water ingress. Subject to weather, safety rules and flight regulations.
Indoor Humidity Monitor
Purpose:
Measures the amount of moisture held within the indoor air (relative humidity and temperature).
Common Uses / Notes:
Helps determine whether high ambient humidity, insufficient ventilation, or surface condensation could be contributing to black mould growth and damp conditions.
Infrared Thermal Imaging Camera
Purpose:
Displays surface temperature variations across walls, floors and ceilings.
Common Uses / Notes:
Assists in identifying cold bridging, condensation risk, insulation irregularities, thermal patterns and hidden water leaks. Interpreted alongside physical moisture readings rather than treated as proof of damp on its own.
Ventilation and Airflow Tester
Purpose:
Tests the extraction performance and airflow velocity of mechanical extractor fans and ventilation outlets.
Common Uses / Notes:
Assesses extractor fans in kitchens, bathrooms and utility rooms to determine whether moisture-producing areas have sufficient extraction rate (L/s or m3/h) to control humidity, condensation and mould risk.
Multi-Gas Detection Equipment
Purpose:
Screens indoor air to identify certain gases present within the property.
Common Uses / Notes:
Supports investigations involving drain smells, suspected sewer gases (H2S, NH3, CH4), combustion concerns (CO, O2) and flammable gases (CH4, C3H8). Does not replace testing or certification by a Gas Safe registered engineer.
VOC and Chemical Vapour Monitor
Purpose:
Screens the air for Volatile Organic Compounds (TVOC/VOC) and chemical substances such as formaldehyde (HCHO).
Common Uses / Notes:
Useful when investigating unusual chemical smells, building material emissions/off-gassing, conditions following water damage, or general indoor air quality concerns.
Fine Particle Monitor
Purpose:
Measures airborne material and particle concentrations across precise size ranges, including PM1.0, PM2.5 and PM10.
Common Uses / Notes:
Supports investigations involving fine dust, smoke, poor indoor air conditions and environments affected by post-leak damage or extensive mould contamination.
Socket and RCD Testing Device
Purpose:
Provides limited, basic electrical safety and protective circuit screening during the inspection.
Common Uses / Notes:
Helps identify certain socket wiring problems, confirms the operation of Residual Current Device (RCD) protection and detects AC voltage in damp areas. Does not constitute a full electrical inspection or an Electrical Installation Condition Report (EICR).
Equipment & Inspection Levels
Essential Damp Survey
Standard price: £299 + VAT
Promotional Price: £199 + VAT (Limited Time Offer)
Repair Deduction: Full survey cost deducted if remedial work is instructed.
The Level 1 survey is an entry-level inspection of the main accessible areas. It is intended for relatively straightforward concerns involving visible damp, suspected rising damp or isolated moisture patches.
Equipment Provided
- Electronic damp meter
Areas and Checks Included
- Accessible walls
- Accessible floors
- Ceilings
- Visible drain and plumbing leak checks
- Damp information and prevention guidance
Recommended For
This option is suitable when a customer needs a basic assessment using a standard damp meter. It can be used for a general check or where there is a simple and clearly defined moisture concern.
The inspection covers accessible internal surfaces, drains and plumbing but does not include the advanced diagnostic instruments provided with the higher survey levels.
The survey price will be deducted if we undertake the recommended remedial work.
Enhanced Damp & Timber Survey
Standard price: £399 + VAT
Promotional Price: £299 + VAT (Limited Time Offer)
Repair Deduction: Full survey cost deducted if remedial work is instructed.
The Level 2 survey includes the Level 1 inspection together with deeper moisture investigation and checks for timber-related deterioration.
Equipment Provided
- Electronic damp meter
- Deep-reading moisture meter
- Non-invasive moisture scanner
Areas and Checks Included
- Accessible walls, floors and ceilings
- Visible drain and plumbing leak checks
- Wet rot inspection
- Dry rot inspection
- Woodworm inspection
- Deeper moisture readings from suitable building materials
- Non-destructive moisture checks beneath accessible floors and within subfloor areas
- Damp information and prevention guidance
Recommended For
It is appropriate for concerns involving wet rot, dry rot, woodworm, concealed dampness or moisture below finished surfaces.
The combination of deep-reading and non-invasive instruments allows the surveyor to gather information from subfloors, beneath accessible floorboards, behind suitable panelling and within other reachable concealed areas without unnecessary dismantling.
The Level 2 survey is a good choice for buyers and sellers who require a more detailed damp and timber assessment before proceeding with a property transaction.
The survey charge will be deducted from the cost of remedial work undertaken by us.
Comprehensive Property Moisture Survey
Standard price: £499 + VAT
Promotional Price: £399 + VAT (Limited Time Offer)
Repair Deduction: Full survey cost deducted if remedial work is instructed.
The Level 3 survey is our most comprehensive inspection. It incorporates the Level 1 and Level 2 services and adds advanced diagnostic equipment, ventilation testing and high-level external inspection.
Equipment Provided
- Electronic damp meter
- Deep-reading moisture meter
- Non-invasive moisture scanner
- Infrared thermal imaging camera
- Indoor humidity monitor
- HD borescope camera
- Airflow and ventilation tester
- 4K inspection drone
- Socket and RCD testing device
Areas and Checks Included
- Accessible walls, floors and ceilings
- Visible drains and plumbing
- Wet rot, dry rot and woodworm
- Deep moisture testing
- Accessible subfloor moisture checks
- Thermal imaging
- Indoor humidity measurement
- Borescope examination where appropriate
- Brickwork and pointing
- Visible damp-proof course
- Extractor fan airflow
- Roof coverings
- Chimney stacks
- Flashing and guttering
- High-level external components
- General visible structural condition
- Basic socket and RCD screening
- 4K drone photographs where flight conditions permit
Recommended For
This option is suitable when a customer needs a basic assessment using a standard damp meter. It can be used for a general check or where there is a simple and clearly defined moisture concern.
The inspection covers accessible internal surfaces, drains and plumbing but does not include the advanced diagnostic instruments provided with the higher survey levels.
The survey price will be deducted if we undertake the recommended remedial work.
Specialised Laboratory Testing Add-Ons
Laboratory Analysis of Plaster Samples
Price £299 + VAT
(The cost of this add-on is deducted from your repair bill if we carry out the recommended remedial works).
Small plaster samples are carefully taken from affected walls and sent to an independent laboratory to analyse the concentration of hygroscopic salts (chlorides and nitrates).
Why it matters: Hygroscopic salts are carried by ground moisture during rising damp and remain in plaster even after masonry dries.
Diagnostic value: Differentiates true rising damp from condensation, rainwater penetration, or temporary plumbing leaks.
Note: Salt analysis can be particularly helpful when moisture-meter readings alone do not provide a sufficiently clear diagnosis. It may assist in distinguishing possible rising damp from condensation, water penetration or residual contamination caused by a historic leak. The results are considered together with the moisture profile, construction of the building, external ground levels, condition of the damp-proof course and other survey observations. This is the only additional service requiring minor invasive work because physical plaster samples must be collected. If we undertake the recommended remedial work, the survey cost will be deducted from the cost of that work.
Laboratory Mould & qPCR DNA Analysis
Surface swab or lift samples are submitted to an accredited laboratory for advanced qPCR DNA testing to identify exact mould species and spore concentrations.
Why it matters: Identifies toxigenic species (e.g., Stachybotrys chartarum) and concealed mould growth behind dry lining or furniture.
Diagnostic value: Establishes whether mould contamination is localised or widespread, enabling precise environmental remediation planning.
This service may be beneficial where:
- A persistent musty smell is present
- Mould repeatedly returns after cleaning
- The property has experienced previous water damage
- Contamination is suspected behind furniture or inside cupboards
- Occupants have concerns about the indoor environment
- The extent of visible mould is unclear
- Independent laboratory evidence is required
Note: The results can help establish whether contamination appears isolated or more widespread. They may also assist with planning appropriate cleaning, removal, drying, ventilation or moisture-control measures. Laboratory mould testing does not replace the need to investigate the moisture source. Mould is normally a symptom of excess moisture, condensation, leakage or inadequate ventilation, so the underlying cause must also be identified. If we carry out the recommended work, the survey fee will be deducted from the cost of that work.
Gas, Vapour & Airborne Contaminant Screening
Price £299 + VAT
(The cost of this add-on is deducted from your repair bill if we carry out the recommended remedial works).
Comprehensive environmental air quality screening for properties with persistent odours, post-flood contamination, or air quality issues.
Screening includes:
- Indoor air-quality assessment – IAQ
- Volatile organic compounds – TVOC/VOC
- Formaldehyde – HCHO
- Fine airborne particles – PM1.0, PM2.5 and PM10
- Dust and smoke particles – PM1.0, PM2.5 and PM10
- Sewer gas screening – H2S, NH3 and CH4
- Flammable gas screening – CH4 and C3H8
- Carbon monoxide – CO
- Hydrogen sulphide – H2S
- Ammonia – NH3
- Oxygen levels – O2
- Stale-air and ventilation assessment – IAQ and TVOC
- Drain odour investigation – H2S, NH3 and CH4
- Chemical smell investigation – TVOC, VOC, HCHO and NH3
- Post-leak air and surface-condition checks – PM2.5 and TVOC
- Combustion gas screening – CO, O2 and CH4
- Building-product off-gassing assessment – TVOC and HCHO
- General pollutant screening – PM1.0, PM2.5, PM10 and TVOC
Diagnostic value: Pinpoints the source of foul drain odours, chemical off-gassing and stale air problems linked to poor ventilation. It is also useful when a property contains a persistent foul, stale or unexplained smell. Odours can originate from damp building materials, stagnant water, contaminated drains, sewer gases, mould-related conditions or chemical vapours. Targeted screening helps narrow down the possible source and supports further investigation.
Note: Screening results do not replace specialist gas, environmental or medical assessments where these are required. The survey charge will be deducted if London Damp Specialists completes the recommended remedial work.
