Very good point and article!
I was doing a water intrusion inspection (out of dire necessity) yesterday in the sunlight.
I told the client that John Snell would slap my knuckles with a ruler if he knew what I was doing!
The client spent $24,000 on engineers to fix water leaks around windows of his new house last year. After 15 inches of rain last weekend, water started flowing again! If I didn’t get out there following these weather conditions, I may not have had another opportunity so I elected to try to do this job under adverse testing conditions.
Though he is a military pilot and uses Flir imaging on a daily basis, it didn’t dawn on him until yesterday to find someone to scan his house (even though he thought about flying is helicopter by ) so there were several days of extreme sunlight on the building prior to my arrival.
It was extremely difficult to locate water intrusion in the extreme sunlight.
Saturated wall, window and hardwood flooring was easy to evaluate with electronic moisture testing (once you knew where to “stick it”) however thermal imaging anomalies where extremely subtle.
I see many thermal scans posted that come directly out of the camera and are not properly tuned.
In the scan below we were concentrating on moisture intrusion below the windowsill which was flowing out from the wall plate inside the garage. Note the electric switch as the scan is tuned from the automatic camera settings.
There was an opening in the wall behind the electrical box that was sealed.
There were also numerous moisture entry points where window remediation practices failed.
The client had already started re-caulking window cracks before my arrival which hindered a visual inspection.
The delta-T and delta-h were practically nil.
To say the least, this was an extremely challenging diagnostic.
Camera sensitivity and resolution becomes critical under these circumstances and extensive use of computer software manipulation is absolutely necessary.
We must know our limitations and control our clients expectations when attempting diagnostics under marginal conditions!