~ Summary ~
Using high-resolution thermal imaging, we conducted a detailed inspection of a commercial roof to identify potential water ingress issues. The survey revealed thermal anomalies, indicating possible moisture retention or unbonded membrane sections beneath the waterproof layer. Conducted at optimal environmental conditions, this non-invasive investigation provided GPS-referenced thermal data, enabling the client to target affected areas for further assessment. By detecting roofing issues early, this inspection helped prevent costly structural damage and ensure long-term waterproofing integrity.
Introduction
A newly installed waterproof roofing system at a commercial building in London was suspected of water ingress issues, potentially compromising the structure’s insulation and longevity. The client, requested a thermal imaging inspection to identify potential moisture buildup beneath the roofing membrane. Detecting water ingress early is crucial, as trapped moisture can lead to deterioration of insulation materials, thermal inefficiencies, and long-term structural damage.
To conduct this assessment, a ground-based thermal inspection was carried out using high-resolution thermography equipment. The inspection aimed to detect thermal anomalies that could indicate the presence of moisture beneath the roofing surface. As water retains heat longer than surrounding materials, thermal imaging was performed after sunset to observe heat retention patterns that might signal hidden moisture issues.
Commercial Roof Inspection, Thermal Imaging for Water Ingress, Building Thermography, Waterproofing Assessment, Infrared Moisture Detection, Roof Leak Investigation, Non-Invasive Thermal Survey, Flat Roof Water Damage, Construction Quality Control, Thermal Mapping for Building Surveys
Scope of Work
The thermal survey was conducted 45 minutes before dusk, ensuring that the roof surface was free from solar gain, which could otherwise interfere with thermal readings. This approach provided the most accurate detection of heat-retaining moisture. By employing this non-invasive technique, the inspection was able to highlight thermal discrepancies without the need for destructive testing.
The inspection process included:
Roof Structure and Material Considerations
Understanding the composition of the roof was essential to interpreting thermal anomalies correctly. The roofing system comprised:
- Concrete base layer, providing structural support.
- MOY Rockwool insulation, a material that can retain moisture if compromised.
- Knauf Aquapanel sublayer, contributing to overall waterproofing.
- Paraflex ARD/S waterproof membrane, installed as the primary protective barrier against water ingress.
Since the waterproof membrane was suspected to be fully bonded to the substructure, the inspection sought to determine whether thermal anomalies were caused by trapped moisture or unbonded air pockets within the system.
Challenges & Solutions
Distinguishing Moisture from Air Pockets
- Challenge: Both moisture retention and unbonded air pockets can produce similar thermal signatures, making it difficult to conclusively determine the cause of detected anomalies.
- Solution: A combination of temperature gradient analysis and additional physical inspections was used to differentiate between the two conditions.
Environmental Impact on Thermal Readings
- Challenge: External environmental factors, such as solar exposure and wind conditions, can affect thermal readings and create false positives.
- Solution: The survey was conducted after sunset, when heat dissipation from the roof was at a natural cooling stage, enhancing the accuracy of thermal detection.
Verification of Anomalies Through Additional Testing
- Challenge: The thermal imaging inspection indicated possible moisture retention, but could not confirm if the waterproof membrane was actively failing.
- Solution: Further invasive testing or moisture probe assessments were recommended to verify findings and confirm the presence of water beneath the membrane.
Key Findings
Thermal Anomalies Detected
The inspection identified several thermal anomalies, with temperature differences exceeding 3°C in multiple locations. These anomalies were categorized as:
- Potential moisture retention: Areas exhibiting prolonged heat retention suggested possible trapped water beneath the membrane.
- Unbonded waterproof membrane sections: Certain areas displayed thermal irregularities, likely due to air pockets where the roofing membrane was not properly bonded.
- Thermal bridging effects: Some elevated temperature zones were associated with underlying structural elements, rather than water ingress.
Influence of Installation Factors
During the analysis, it was observed that thermal variations were not uniform, suggesting multiple contributing factors:
- Material bonding inconsistencies: Some sections of the waterproof membrane appeared to be loosely bonded, creating air pockets that mimicked moisture-related thermal patterns.
- Insulation condition: The presence of Rockwool insulation raised the possibility that some anomalies were due to moisture absorption at the time of installation, rather than active water ingress.
- Structural elements affecting temperature: Areas with steel supports and overlapped material seams exhibited higher thermal readings, likely due to thermal bridging rather than leaks.
