Damp Proofing Specialists in London: Extensive Expertise and Coverage

Description: An aerial structural inspection employing ultra-high-definition 4K drone cameras to evaluate roof coverings, chimney stacks, flashings, rainwater goods and external elevated fabric. The survey captures clear photographic and video records of visible defects, wear, weathering and required maintenance in areas unreachable or hazardous to inspect from the ground.

Value: Supplies clear, documented photographic and video evidence of external building envelope faults without requiring direct physical access or the considerable cost of scaffolding. It allows penetrating damp sources to be identified at high levels so that external repair works can be planned accurately.

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.

Description: Utilises a specialist air-sampling pump to capture circulating airborne mould spores within internal living spaces, combined with outdoor comparative air sampling where suitable. Collected samples are submitted to an accredited testing laboratory to evaluate spore concentrations and identify specific mould categories where viable.

Value: Surface swabs only identify mould DNA present on a targeted structural material; an air pump test directly evaluates the spores actively travelling through your indoor air. This provides essential diagnostic data when assessing suspected airborne mould issues, particularly when contamination is hidden and no visible mould has broken through onto surfaces.

Note: Air pump analysis measures active spore levels at the specific time of collection. Diagnostic results are reviewed alongside exterior control samples, internal damp meter readings, ventilation performance and observed structural conditions. Survey fee credited when repairs are completed by us.

(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.

(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.

Description: A specialist diagnostic testing service established to locate and identify biological deposits, organic residues and environmental contaminants across domestic and commercial premises. Samples are obtained via sterile surface swabs, targeted material sampling, or appropriate extraction techniques, followed by professional laboratory analysis.

Value: Uncovers concealed biological matter and hazardous organic residues that cannot be detected through visual inspection alone. Independent laboratory testing delivers definitive evidence regarding bodily fluids, waste ingress, bacterial risks and animal contamination, ensuring that decontamination and repair treatments are accurately targeted.

Testing categories can include:

• Human bodily fluids: Blood and suspected blood residues; urine and urine residues; semen and suspected semen residues; saliva and saliva residues; and other suspected bodily fluid residues (subject to laboratory capability).
• Human waste and associated contamination: Faecal matter and suspected faecal residues; biological residues linked to human waste; and laboratory indicators of faecal contamination where test protocols exist.
• Animal waste and biological residues: Domestic and pest animal droppings; animal urine saturation; animal bodily fluids (subject to laboratory capability); and biological residues linked to active infestation in sub-floors and cavities.
• Bacterial contamination: General bacterial presence; specific bacterial indicators connected to sewage and waste contamination; and targeted bacterial organisms where laboratory testing is available.
• Other biological and organic residues: Suspected organic deposits on floors, wall plaster and timber surfaces; residues resulting from human or animal activity; and unidentified mixed biological contaminants.

Note: The designated testing method depends on the material investigated, the contaminated substrate and the necessary degree of laboratory identification. The survey fee is credited when repairs are completed by us.