ORTHOSBy the time a roof leak shows up as a stain on a ceiling, water has usually been sitting in the roofing system for weeks or months. The material got wet, dried a little, got wet again, and the damage compounded quietly the entire time. Thermal imaging catches that trapped moisture while it's still invisible from both the roof surface and the ceiling below.
Why trapped moisture shows up as heat
Wet insulation and wet roofing material hold heat differently than dry material — they absorb heat during the day and release it more slowly after sunset than the dry sections around them. A thermal camera doesn't see moisture directly; it sees the temperature difference moisture causes. That's why timing the flight right matters as much as the camera itself.
How this differs by roof type
| Roof type | What the thermal signature looks like |
|---|---|
| Flat / membrane | Clear, well-defined moisture pockets — the easiest roof type to read |
| Composition shingle | Broader, softer-edged warm zones tracing the underlying deck |
| Tile | Signature reads through the tile but is muted — usually needs a slightly longer post-sunset window |
None of these are guesswork once you know what you're looking at, but a report on a tile roof and a report on a flat commercial roof shouldn't be read the same way — the annotation on each accounts for that.
Roof moisture vs. solar hot-spot detection
The same thermal sensor covers two different jobs. On a roof, the target is trapped moisture — a warm signature standing out against a dry background. On a solar array, the target is the opposite pattern: an underperforming or failing panel runs hotter than its neighbors because it's not converting sunlight into electricity efficiently, so the defective cell shows up as a bright spot against an otherwise uniform field.
Timing after a storm
Post-storm documentation works best as soon as it's safe to fly — ideally within a few days. Fresh moisture intrusion has the clearest thermal signature; the longer it sits, the more the material dries unevenly and the harder the pattern is to read cleanly. This is also the window insurance adjusters care about most, since it ties the damage most directly to the event.
What the report actually includes
- Annotated thermal map — anomalies marked directly on the image.
- Paired visible-light photo — the same spot shown in a normal photo for reference, so the finding isn't just an abstract heat map.
- Flagged coordinates — specific locations called out, not a generic "check the roof" summary.
Frequently asked questions
Does thermal roof inspection work on any roof material?
Yes — flat/membrane, composition shingle, and tile roofs all show a moisture signature, though how clearly it reads and the best flight timing varies by material.
How soon after a storm should a thermal scan happen?
As soon as it's safe to fly, ideally within a few days. Fresh moisture intrusion has the clearest thermal signature before conditions dry unevenly and the pattern becomes harder to read.
Can thermal imaging find failing solar panels too?
Yes — the same sensor detects underperforming or failing panels, which run hotter than neighboring panels due to inefficient energy conversion, visible in a single low-altitude pass over the array.
Orthos Aerial Group runs thermal roof and solar inspections across the Sacramento Valley — Redding to Sacramento.