Commercial Roof Moisture Inspection
A full-roof thermal moisture map for flat and low-slope commercial roofing — flown at night, when trapped moisture reveals itself as a heat signature the naked eye can't see.
Trapped moisture under a flat or low-slope commercial roof membrane (EPDM, TPO, built-up, or modified bitumen) is one of the most common and most expensive-to-ignore roofing problems, because it's almost always invisible from a visual inspection. By the time a leak shows up on the ceiling below, the wet insulation has often been degrading the roof system from underneath for months or years.
Roof moisture surveys work on a different thermal principle than an insulation scan: wet material has higher thermal mass than dry material, so it absorbs heat during the day and releases it more slowly after dark. On a sunny day followed by a clear night, dry sections of the roof cool off quickly once the sun sets, while wet or saturated sections stay measurably warmer for hours — a heat signature that shows up clearly on a thermal camera even though the surface looks completely normal to the eye. This is why moisture surveys are flown after dark, a few hours past sunset, once the roof has begun cooling but before the whole surface equalizes.
A drone-flown survey covers the entire roof from a consistent top-down (nadir) angle in a single pass, producing a stitched, distortion-free moisture map — something a technician walking the roof with a handheld unit can't reliably reproduce, especially on large, multi-section, or steep-pitch commercial roofs.
Why it's requested
- Full-roof coverage in a single flight, including sections that are difficult or unsafe to walk
- Detects trapped moisture well before it causes a visible interior leak or ceiling stain
- No foot traffic on the membrane — reduces the risk of accidental puncture or wear from a walked survey
- A dated, GPS-tagged moisture map you can use for maintenance planning, capital budgeting, or contractor bid comparisons
Why moisture surveys are flown at night
The whole roof heats up under direct sun during the day, but wet and dry areas release that stored heat at different rates once the sun goes down. Dry insulation and substrate cool quickly; saturated areas hold residual heat longer, creating a temperature differential that's often modest — commonly just a few degrees — which is exactly why a high-sensitivity radiometric thermal camera and an experienced interpreter matter more than raw image resolution.
We schedule flights around the conditions that produce a clean read: a sunny, warm day followed by a clear night with a real temperature swing between daytime peak and scan time. Rain, high humidity, and heavy wind in the hours before a flight can all distort or wash out the moisture signature, so weather-dependent rescheduling is a normal part of doing this correctly.
What you'll see in your report
Every survey delivers a full-roof thermal map with suspected moisture zones outlined and ranked by apparent severity, paired with matching visual-light imagery and plotted against a roof plan where available.
- Full-roof thermal moisture map with flagged zones plotted by location
- Radiometric temperature data behind each flagged anomaly, not just a color image
- Matching visual-light imagery for every flagged zone
- GPS-tagged, timestamped captures suitable for maintenance records or capital planning documentation
Supporting your claims process, without being part of it
If a roof leak or storm event has already caused damage, a dated, GPS-tagged thermal survey and report can serve as independent, third-party documentation that you or your contractor provide to your insurance adjuster as part of your own claims process. We're a drone inspection service — we document what the roof shows, we don't handle, file, or negotiate anything on your behalf, and we don't work for or represent any carrier.
Ideal for
- Property managers and REITs maintaining a portfolio of flat or low-slope commercial roofs
- Facility managers planning roof maintenance, repair, or replacement budgets
- Roofing contractors who want an independent moisture map before scoping a repair or re-roof
- Building owners who've noticed an interior leak or stain and need to find the actual source
What affects the cost
Roof Moisture Survey questions, answered
Wet roofing material holds heat longer than dry material after sunset, which is exactly the temperature differential a moisture survey is built to detect. Flying during the day, while the whole roof is heated by direct sun, washes out that contrast.
Often, yes. Moisture frequently spreads laterally under a membrane before it ever reaches a point where it drips through to the interior, so a thermal survey can flag saturated areas well before a ceiling stain appears.
We provide a dated, GPS-tagged inspection report that you or your contractor can use as supporting documentation in your own claims process. We're an independent inspection service — we don't file claims, represent any insurance carrier, or provide insurance products of any kind.
A thermal survey is a non-invasive screening tool that identifies where moisture is likely present so a roofing contractor can target physical core samples or moisture-meter checks to the areas that actually need them — it's a fast way to narrow down where invasive testing is worth doing, not a replacement for it.
Related services
Ready to request a roof moisture survey?
Tell us about your property and we'll dispatch an FAA Part 107 certified pilot to map insulation gaps, roof moisture, or heat loss — with a clear report in your hands within days.