Thermal drone surveys & aerial thermal imaging across the UK

A thermal camera measures infrared radiation emitted and reflected by surfaces and presents the differences as a thermal image. The image represents apparent surface temperatures. It does not allow the camera to see inside a roof, a wall or an electrical component.

Temperature patterns in a thermal image may be influenced by many factors, including:

• Surface material and emissivity
• Reflections from surrounding surfaces and the sky
• Solar heating and residual stored heat
• Wind, rain and recent rainfall
• Ambient temperature and the internal to external temperature difference
• Time of day
• Sensor type and resolution
• Viewing angle and flight distance
• Capture methodology

Good drone thermography therefore depends as much on capture conditions and method as it does on the equipment.

Thermal imagery can help identify

Thermal imagery may help identify unusual temperature patterns that could warrant closer investigation, such as:

• Unexpected hot areas
• Unexpected cold areas
• Temperature variation across a roof
• Potential insulation inconsistencies
• Areas showing unusual thermal behaviour
• Solar modules behaving differently from surrounding modules
• Electrical or mechanical components showing elevated surface temperatures

Thermal imagery does not automatically confirm

• The presence of water or moisture
• The precise source of a leak
• The cause of an insulation problem
• Structural defects
• Electrical failure
• The severity of a defect
• Whether repair is required
• Compliance with a particular professional standard

Thermal evidence should be interpreted in the context of the asset, environmental conditions and purpose of the inspection. Further testing or specialist interpretation may be required.

Thermal cameras do not directly see moisture. Under suitable conditions, moisture can influence the thermal behaviour of materials and create temperature patterns that may help identify areas for further investigation.

Confirmation of moisture or the source of water ingress may require additional inspection or testing. Thermal capture is often requested alongside drone roof surveys so that visible roof condition and thermal patterns can be considered together.

For suitable buildings and environmental conditions, thermal imagery can help visualise temperature differences across the building envelope and identify areas that may warrant further energy efficiency investigation.

Potential applications include:

• Building envelope investigation
• Roof temperature variation
• Insulation inconsistencies
• Thermal bridging
• Heat loss patterns
• Façades and high level elevations
• Commercial property and industrial buildings

The conditions required for useful thermal capture depend on the building and purpose of the survey, so timing is assessed as part of the assignment. Building thermal surveys can also be combined with drone building inspections where visual condition is also relevant.

Thermal aerial capture may be useful for certain roof investigations where temperature patterns across the roof surface are relevant.

• Flat commercial roofs
• Industrial roofs
• Large roof areas
• Investigation of unusual thermal patterns
• Supporting further investigation of suspected insulation or moisture issues

The suitability of roof thermography depends heavily on roof construction, environmental conditions and the purpose of the inspection. See drone roof surveys for visual roof capture, or drone inspection services for the wider inspection range.

Where suitable conditions and specialist capability are available, thermal drone imagery can help identify modules or areas of an array displaying temperature patterns different from surrounding panels.

• Module level thermal anomalies
• Hot spots
• Comparative array inspection
• Larger solar installations

Thermal imagery highlights temperature behaviour rather than confirming the electrical cause, which normally requires specialist interpretation or testing. More detail is available on solar panel drone inspection.

Thermal imagery is often most useful when considered alongside standard visual imagery so the thermal pattern can be related to the physical asset being inspected.

Potential outputs may therefore include:

• Thermal imagery
• Corresponding visual imagery
• Site overview imagery
• Individual areas of interest
• Other agreed capture

Where aligned visual and thermal capture is required, this should be specified within the brief.

Deliverables are agreed according to the purpose of the assignment and customer requirements.

Potential outputs may include:

• Thermal imagery
• Radiometric thermal files where appropriate and supported
• Visual reference imagery
• Annotated imagery where specifically agreed
• Temperature information where appropriate
• Original files where agreed
• Other agreed evidence or data formats

Where specialist thermography interpretation or a particular report format is required, this should be identified before the assignment so suitable capability can be confirmed.

Thermal imagery may support insurance, loss adjusting, property and facilities management workflows where temperature data is relevant to the investigation.

Evidence and reporting requirements vary according to the organisation, claim and intended use, so any specific requirement should be agreed before the assignment.

Depending on the assignment, Drone Assisted may match the requirement with a pilot operating suitable radiometric thermal equipment.

Radiometric thermal cameras can record temperature information associated with individual image pixels, supporting more detailed analysis where temperature measurement is required.

The appropriate sensor depends on the asset, required output, measurement requirement and intended use of the data. Where a specific sensor specification, resolution, measurement accuracy or calibration status is needed, it should be raised in the brief so capability can be checked for that assignment.

Drone Assisted checks pilot identity, commercial drone insurance and appropriate CAA registration as part of network onboarding.

Where thermal capability is required, the assignment is assessed for suitable equipment and relevant pilot experience. Additional competency, qualifications and Operational Authorisation are checked where required for the proposed operation.

The exact regulatory requirements depend on the aircraft, location, surrounding environment, airspace and nature of the assignment. See commercial drone pilot requirements for how UK rules apply in practice.

Some assignments may require specialist thermography interpretation or recognised thermography competency in addition to drone operating capability. Where this is required, it should form part of the customer brief. Professional thermography qualifications are available through organisations such as BINDT. Where a particular qualification is required for the intended use, Drone Assisted can assess that requirement when sourcing suitable capability.

Where building surveying, engineering, electrical or other professional interpretation is required, thermal imagery can be supplied as part of the agreed evidence for an appropriately qualified specialist to assess.

Our approach to pilot standards reflects the principles of safety, professionalism and responsible drone operations promoted by organisations such as ARPAS UK.

The best capture conditions depend on what is being investigated. Building envelope, roof, electrical and solar applications can require very different environmental conditions.

Potential considerations include:

• Temperature difference
• Solar loading
• Cloud cover
• Wind
• Rain and recent rainfall
• Surface material
• Time of day
• Intended measurement

The appropriate timing and conditions should therefore be assessed as part of the assignment rather than applying one standard rule to every thermal survey.

• Site address or postcode
• Asset type
• What is being investigated
• Reason for the survey
• Intended use of the thermal data
• Area requiring capture
• Any previous inspection information
• Required outputs
• Whether professional thermography interpretation is required
• Deadline
• Site access information
• Known operational restrictions

Not sure whether thermal capture is the right solution? Tell us what you are trying to investigate and we can assess whether thermal drone capability may be appropriate. Discuss your thermal requirement.

Potential users of aerial thermal imaging and thermal inspection services can include:

• Facilities managers
• Property managers
• Commercial landlords
• Building surveyors
• Insurers and loss adjusters
• Roofing businesses
• Solar operators
• Energy businesses
• Industrial organisations
• Maintenance teams
• Construction companies

Pricing varies according to the asset, location, required thermal capability, survey conditions, site size, output requirements and any specialist interpretation needed.

Indicative pricing for straightforward residential and smaller commercial thermal assignments may fall around £300 to £600. Larger commercial or specialist assignments may fall around £600 to £1,500 or more depending on the requirement. Complex energy, industrial and large area projects are priced individually.

The price is confirmed before the assignment proceeds.