The recent storm season has hit the Houston, Texas area particularly hard. From catastrophic structural damage to long stretches without power, the Houston area has been indiscriminately wrecked by inclement weather over the last several weeks.
Severe weather (particularly in Texas) always means all kinds of structural damage, to include roof damage. And when it comes to flat roofs that are already inherently susceptible to moisture issues, the odds of significant damage are significantly higher.
Assessing Roof Condition With a Thermal Drone
One of our long-time clients reached out regarding an infrared roof inspection of a property down in the Houston area. This roofing company has been chosen to work on the roof of a moderate-sized building in a small industrial business park area.
Given the recent weather phenomena, it was assumed that the roof would likely be in bad shape. However, the extent of the damage is critical information for the roofing contractor, as it will enable them to better forecast material and time requirements to complete the project.
So, we loaded up our equipment (the DJI Mavic 3T in this case) and made the drive down south to Houston.
After arriving on site, we did a thorough area walk around to check the area for obstacles. There were some trees close to the building, but we were able to take note of their exact location and approximate altitude to deconflict with our drone’s mapping flight plan (more on that shortly).
We then checked the surrounding airspace to determine whether we would need to obtain a LAANC clearance to fly — in this case, a clearance wasn’t required. The final step was to secure on-demand liability insurance, then we were ready to get started with the thermal roof inspection.
2D Thermal Map
Depending on the scope of a particular project, we like to create a 2D thermal map of the roof to include in our final inspection report. We describe this product as a Google Maps view overlaid with thermal data captured during the inspection.
Below you can see the thermal map we generated for this project. This particular map is comprised of 241 individual thermal photos that were taken at various points over the roof.
As you can see, this product provides a high level of detail regarding the roof’s condition from an infrared radiation standpoint. At a glance, the client can quickly ascertain whether this roof is experiencing moisture ingress issues, and if so, where the “hot spots” are.
This is a great tool/product to show everyone in the office; everyone can quickly gauge the extent of the damage on the roof of an upcoming project.
As we suspected, this roof appears to have a significant amount of surface area that appears to have moisture issues. The southwest corner of the roof was tarped off, so we can safely assume that there is likely even more moisture damage under the cover.
As a quick side note, you likely noticed what appear to be pools of liquid depicted in bluish-purple on the thermal map. Though this might appear to be water, these are actually areas where sediment/dirt/debris has accumulated on the roof’s surface.
However, it can still be important to take note of these areas, as these are likely the “low” spots where standing water accumulates on the roof and ultimately deposits this debris. Given enough time and wear and tear from the elements, the roof is likely to allow water ingress around these points, as these are points where moisture collects.
But for the purposes of analyzing the roof as it currently is in terms of moisture intrusion, the brighter “hot” spots are what we’re interested in, as these are the areas that are currently harboring moisture.
Capturing Thermograms Manually
In addition to autonomously capturing the thermograms that will be stitched together to generate the thermal map, we spent the majority of the inspection time manually capturing thermograms to include in the final report.
We flew the drone over the entire roof structure and strategically captured images to report our findings. Below is a selection of thermograms we manually captured during the inspection.
As you can see, there appears to be a significant amount of moisture being held under the roof membrane. The majority of the suspected moisture is concentrated near the central portion of the roof, but it extends outward to all but one edge.
As a side note — we typically capture thermograms in the two color palettes seen above. In our experience, these palettes best show the data in an easy-to-digest format.
The End Product
So, what did our client receive at the conclusion of this project? The end product was a thermal report with the 2D map pictured above along with some manually captured thermograms.
During the post-processing stage of our workflow, we narrowed our batch of photos down to 12 photos to include in the report.
Take a look at the final thermal report below.
With this thermal drone roof inspection report in hand, the roofing company can now better plan for this project. You might be thinking — isn’t it just a roof replacement? Why was this level of inspection necessary?
Even if a roofing company knows that they will be replacing a roof, a thermal drone roof inspection can be invaluable, as it sheds light on underlying problems that, if not properly planned for, can significantly delay project completion.
Given the amount of suspected moisture damage seen in the thermograms, it is overwhelmingly likely that the foundation of this roof has rot, insulation, and mold issues. Now equipped with this knowledge, the roofing company can plan for a more thorough restoration effort in conjunction with a standard roof replacement rather than be blindsided by this revelation when they start tearing up the roof.
The end result is a more realistic timeline and a better, more strategic allocation of resources. And this is all information that would have been impossible to know without an aerial infrared inspection.
The Bottom Line
Not only is this another successful thermal drone roof inspection project in the books, but it is a step toward helping Houston’s infrastructure recover from a series of relentless storms. We’re just happy that we could play even a small role in restoring a piece of infrastructure.
To learn more about our thermal roof inspection process, take a look at our service page.
