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How Do Surveyors Find Damp?

Dampness is a serious problem that occurs in around 4% of all houses in the UK, and it is capable of causing serious structural damage and even causing health issues if left unchecked. Whether it’s the result of leaks, condensation, or structural defects, dampness can detriment the integrity of a structure, leading to costly repairs and health hazards for occupants. However, highly-trained surveyors can find dampness, along with the help of specialist equipment and tools, to remove and prevent it from reoccurring. 

Surveyors use a variety of techniques to find damp. Visual inspections come first, scanning for stains, discolouration, and mould growth. Moisture meters are then used to measure moisture content in materials, while thermal imaging cameras identify hidden moisture behind walls or under flooring.

In this article, we will take a look into the techniques and tools utilised by surveyors to identify damp. This will provide a good understanding of how specialist damp surveyors find, analyse and take action against dampness.

The Methods for Finding Dampness

When it comes to finding dampness within a property, surveyors use a variety of approaches. Each of these methods has valid reasoning for existing within their overall approach, as each will help to find different issues or signs of damp. Let’s take a look into these methods for finding dampness: 

Visual Inspection

Visual inspections stand as one of the most important methods for discovering dampness within buildings. Through a thorough examination of both the interior and exterior, expert surveyors have the skills needed to search for dampness in the correct areas. From water stains and discolouration to peeling paint or wallpaper and visible mould growth, a surveyor with enough knowledge and expertise will find these. This comprehensive approach allows surveyors to identify potential problem areas and create a tailored remediation strategy. 

Moisture Meters

Moisture meters are an indispensable tool for surveyors, as they provide precise measurements of moisture levels within various building materials. Using probes or sensors, surveyors can delve into materials such as wood, drywall, and plaster, accurately gauging moisture content within them. This approach enables the identification of areas susceptible to dampness. By providing quantitative data, moisture meters allow surveyors to make informed decisions regarding the severity of moisture issues and the appropriate course of action. Whether assessing the extent of water damage or monitoring moisture levels during construction or renovation projects, these devices play an extremely important role in maintaining the structural integrity and longevity of buildings. 

Thermal Imaging

Thermal imaging is a powerful technique used by surveyors to detect moisture buildup within building structures. By capturing temperature variations on surfaces, thermal cameras unveil potential dampness concealed behind walls or beneath flooring. These devices distinguish subtle differences in thermal properties, determining temperature differences between damp areas from dry ones. This enables surveyors to pinpoint moisture infiltration with precision, which then allows for a method of remedying the issue. Through thermal imaging, surveyors can identify hidden moisture issues early, preventing further damage and minimising the risk of mould growth. 


Hygrometers play a pivotal role in damp surveys, as they allow for the assessment of indoor humidity levels which is crucial for dampness detection. By measuring relative humidity within the air, these tools identify areas of excessive moisture that may signify underlying damp issues. Surveyors use hygrometers to gauge environmental conditions, pinpoint potential moisture sources and assess the risk of mould growth. 

Probing and Sampling

In situations where visual inspection and moisture meters are inconclusive, surveyors may resort to probing and sampling techniques for a more in-depth analysis. This may involve drilling small holes into walls or extracting material samples for laboratory testing, providing valuable insights into the extent of moisture damage and the presence of mould or other contaminants.

Building History and Documentation

Surveyors also rely on the building’s history and documentation to glean insights into past moisture problems or maintenance issues. Reviewing previous inspection reports, maintenance records, and renovation history can help surveyors identify recurring dampness issues and formulate effective remediation strategies tailored to the specific needs of the property.

Methods of Remedying Dampness

Specialist surveyors utilise a variety of advanced techniques and strategies to effectively address dampness in buildings, tailoring remediation methods to the specific type of dampness and underlying causes.

Installation of Damp-Proof Membranes or Barriers

One commonly used method involves installing damp-proof membranes or barriers. These barriers are designed to prevent moisture from infiltrating the building structure, effectively halting dampness at its source.

Improvement of Ventilation Systems

Surveyors may recommend improving ventilation systems to reduce humidity levels and prevent condensation buildup. By enhancing airflow within the building, ventilation improvements help mitigate the risk of dampness and promote a healthier indoor environment.

Targeted Treatments such as Biocide Application or Mould Removal

In cases of severe dampness or mould infestation, specialist surveyors may implement targeted treatments such as biocide application or mould removal. These treatments are designed to eliminate existing moisture sources and prevent further damage, restoring the building to a dry and safe condition.


In conclusion, the detection and remediation of dampness within buildings are critical aspects of property maintenance and management. From identifying the subtle signs of moisture infiltration to implementing targeted remediation strategies, specialist surveyors play a vital role in safeguarding the structural integrity and health of buildings. 


What are the common signs of dampness in buildings?

Common signs include water stains, discolouration, peeling paint or wallpaper, musty odours, and visible mould growth.

What are the potential causes of dampness in buildings?

Dampness can result from leaks, condensation, poor ventilation, rising damp from the ground, or defects in the building envelope.

What health risks are associated with dampness and mould in buildings?

Dampness and mould can exacerbate respiratory issues, allergies, and asthma, and may lead to other health problems if left unaddressed.

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