We were recently contacted to quote a thermal drone roof inspection of a set of three large roofs in Carrollton, Texas. This area is part of a massive business park. The roofing company that reached out to us was already planning on doing a complete roof layover, and they wanted the thermal drone roof inspection to provide additional situational awareness on potential moisture issues before starting the project.
At roughly 750,000 square feet, this would be the single largest thermal drone roof inspection project we would do to date. Below, we’ll discuss our thought process on planning this inspection project and how we went about executing it.
Pre-Inspection Planning
As is the case with any thermal flat roof inspection, planning is paramount.
Weather
For a thermal flat roof inspection to yield accurate, actionable data, certain environmental criteria must be met. These include things like recency of rainfall, wind velocity, and general conditions the day prior/of the inspection. For a more comprehensive look at the specific criteria, check out our FAQ page.
This inspection was requested in the middle of a cold spell that lasted several weeks. There was intermittent precipitation and cold, cloudy conditions that weren’t conducive to a good thermal flat roof inspection.
So, we heavily utilized several weather forecast/outlook resources, and we found a 48-hour window where the weather would be suitable for an inspection.
Airspace Authorization
The inspection was location was inside surface-based controlled airspace. This means that authorization from the FAA would be required to fly a drone in this area. Thankfully, the FAA’s LAANC system made it easy to obtain on-demand airspace authorization to fly in that area.
Post-Processing
The inspection was conducted successfully without a hitch. We ended up going out to the location on two separate nights to gather imagery.
The first night, the drone spent about an hour and a half flying an autonomous flight route to capture thousands of individual images that were later stitched into a 2D thermal roof map. The second night, we manually flew the drone and captured thermal images at certain intervals to provide a closer, more detailed look of thermal anomalies present at each roof segment.
Thermal Roof Map
Being our largest flat roof inspection project to date, the post-processing was quite time intensive. First, we had to trim down our 4,000+ autonomously captured images to 4,000 to be compatible with the thermal map software we use. Then, it was simply a matter of letting the software do its thing to create the end product.
Tuning the Thermal Images
Then, we uploaded all of the manually captured thermal images to our thermal post-processing software. We then went through each of the 140+ images, tuned them to maximize the contrast of visible thermal anomalies, and provided remarks on what we saw. This was by far the most time-consuming part of post-processing.
Here are a few of the individual images captured during the inspection.
The Report
Then, we were ready to generate the end product—the report. The report is a PDF document containing the thermal roof map, the tuned thermal images, a brief breakdown of our process, and an analysis of our findings. This is the final product that our clients can incorporate into their processes to support their project.
In Closing
Ultimately, we concluded that a significant portion of the different roof structures in question showed signs of possible moisture ingress. Our client was initially planning on doing a roof layover of these roof structures; now that they are equipped with our preliminary findings regarding potential moisture ingress, their ongoing decision-making process in the project is enhanced.
To learn more about our thermal drone roof inspection service, check out our service page.
