Roofs are a crucial part of any building. They provide structural support, insulation, and keep out bad weather. But to ensure a roof stays in good condition, it needs to be regularly inspected.
Enter drones. Also known as unmanned aerial vehicles (UAVs), they can detect all types of roof issues with highly accurate radiometric thermal sensors. Whether it’s a warehouse or a school, a thermal roof inspection helps keep big flat commercial rooftops in top condition.
In this article, we’ll go over what thermal drone roof inspections are and list five major benefits to implementing into your facility management.
Table of Contents
What are Thermal Drone Roof Inspections?
A thermal drone roof inspection checks for anomalies and defects in a roof. But it also serves as a baseline survey for general maintenance. For example, it can confirm that a roof was installed or rebuilt properly.
No matter the age of your roof, a thermal inspection lets you know everything is in order. Drones equipped with infrared (IR) sensors can scan large roofs in mere minutes. Then, the thermal images are processed by advanced drone software to deliver detailed thermal maps and models. These give you an accurate view of the roof’s condition and potential issues that need your attention.
“The work input to value output with drone-based thermal imagery is game changing. It’s unlike anything else in construction technology right now.”
-Grant Hagen, Virtual Design and Construction Manager at The Beck Group
1. Mitigating Risk
Traditional roof inspections are dangerous. They often lead to falls from climbing tall ladders and trips and slips from skirting unstable surfaces. Sometimes a roof even poses risks of collapse, electrocution, or getting stuck in a confined space. In fact, the work fatality rate for roofers is more than ten times the rate of work fatalities overall.
Fortunately, drones make roof inspections significantly safer. They can cover large roofs while the drone pilot operates from a safe location. They can get all the necessary data and more without putting anyone in harm’s way.
By performing routine drone inspections, you also minimize the risk of roof failures in the future. Identifying roof issues early on helps maintain the health and condition of a building and the occupants inside. Proactivity is key.
2. Valuable Data
Thermal roof inspections performed by manned aircraft capture lower-quality data and less of it. This is because they have to fly at high altitudes which results in lower resolution images. And the lower the resolution, the lower the accuracy.
Drones, however, can fly much closer to the roof for high-resolution thermography. They can also access areas that are harder for larger aircraft and humans to reach. This means they can produce more actionable data for reports and repairs.
Here are some of the issues that a thermal drone roof inspection can uncover:
- Water leaks and moisture. If left unaddressed, these could lead to further water damage like molding or rot.
- Cold spots. These usually occur from cracks or holes in the roof where heat is escaping and can be a huge energy waster.
- Water puddles. You shouldn’t have any water collecting on the roof. If you do, it may be a sign that a gutter or drain is clogged somewhere.
- Shrinkage. Roof materials will expand and contract with changing temperatures. This can lead to cracks and other threats to the roof.
- Blistering. A roof blister is a pocket of air in the roof that is usually caused by heat. This could be a sign of poor ventilation or a manufacturing defect.
Video Credit: Teledyne FLIR
The beauty of drone thermography is that it is highly accurate. For one, infrared data catches minute details. And since drones can be programmed to fly routine routes that repeat the same shots from the same angles, they are even more likely to detect any changes over time. This adds another layer of accuracy that you just don’t get from traditional inspections.
Ultimately, the valuable thermal data helps with preventative maintenance, repairs, recordkeeping, and even funding real estate deals because you have a more accurate assessment of the building’s value.
3. More Efficient and Less Costly
Drone inspections are highly efficient. They reduce inspection time by eliminating the need to transport, assemble, and set up a lot of heavy access equipment like ladders and scaffolding. Typically, the actual inspection (collecting drone data) takes under an hour. Part of this efficiency stems from the ability to pre-program flight routes for autonomous flights. Drone operators can outline the perimeter of a roof and then sit back while the drone does the heavy lifting.
Of course, faster inspections also lead to more cost savings. For one, you don’t need to hire as much manpower for as many man-hours. Drones get the job done in a fraction of the time with one or two operators. This also means you don’t need to worry about insuring as many workers or equipment for liabilities. Plus, hiring out drone equipment is much less expensive than hiring out manned aircraft like helicopters for thousands of dollars per day.
Drone inspections can also be performed more frequently, which allows you to catch and prevent more roof issues in the long run. They are a non-invasive way to inspect roofs and get the most out of your building maintenance budget.
4. Warranty Claims
Most roofs come with a warranty. Typically, manufacturers guarantee their roofs for 10 to 25 years, and installers guarantee their workmanship for up to 2 years. Depending on the warranty, they’ll cover anything from roof leaks to high wind and hail damage to roof punctures. But you should carefully read over the specific terms of the warranty to learn what it will pay for.
A drone thermal inspection can help you detect issues covered under the warranty so you can get the most out of it. While you may be tempted to say “if it ain’t broke, don’t fix it,” you could be saving a lot of money on repairs down the line by catching issues sooner than later. If you wait too long and allow roof defects to get worse, you risk letting the warranty expire before you can derive a benefit from it.
5. Thermal Maps
A thermal map is a detailed visual that shows temperature levels. Also referred to as a heat map, a thermal image uses different colors to indicate different temperatures. These visual cues can show clusters that vary in intensity, so you can easily spot areas of concern and assess the overall condition of your roof.
In the realm of roof inspections, a comprehensive thermal map is an invaluable deliverable that can be put to use immediately while also providing a base line for future inspections.
Video Credit: DroneDeploy
Proceed with Caution When Hiring Drone Pilots
If you want to stay ahead of the curve, get a thermal roof inspection. But be wary of any drone pilot offering thermal roof inspection services who is unlicensed or doesn’t have the proper equipment, experience, or training. You’ll want to do your research and see if they can thoroughly and correctly answer the following questions:
- What are your data acquisition practices for my roofing material? Different materials often require unique settings and considerations. Some common roofing material types include modified bitumen, single ply (TPO, PVC, EPDM), metal, shingle, tile, and coatings.
- Are you a licensed roof inspector or contractor? They will need to be licensed or work directly with someone who is. They should also follow ASTM C1153, the national standard for locating wet insulation in roofing systems with infrared imaging.
- What are the ideal weather conditions for a roof inspection? The roof must be dry, and the inspection needs to be done at night with winds slower than 15 MPH (24 km/h). The best time is an hour after sunset.
If the drone pilot can’t answer these questions satisfactorily, be sure to look for someone else. Remember that hiring an inexperienced inspector will cost you significantly more money in the long run. For example, if the thermal inspection data labels a leak incorrectly, you could start tearing up the roof just to find out there was no issue after all.
A professional UAS pilot with a certification in thermography will be able to accurately provide a wide variety of data beyond differences in temperature. Here are some thermography terminology they should be familiar with:
- Qualitative & quantitative data
- Emissivity
- Gain
- Temp Span
- Auto Tune
- Thermal Tuning
- Spot Size Ratio
- Palettes
- Isotherms
- Blackbody
- Reflected Apparent Temperature
- Instantaneous Field of View (IFOV) and Field of View (FOV)
- Solar Absorption
- Thermal Crossover
- Thermal Shadow
- Environmental Diurnal Cycle
- Solar Reflectance
- Radiometry
- Multi-Spectral Dynamic Imaging
- Flat Field Correction
Thermal drone roof inspections are not just point and shoot either. There are several factors to consider when performing one. A single incorrect setting or miscalculation could render all the data inaccurate and useless. That’s why any drone pilot should be licensed and understand the following:
- FAA Part 107 License
- Airspace knowledge
- Preflight checklists
- Aircraft care and maintenance
- Emergency procedures
- sUAS thermography certification
- Flight planning
- Flying in different flight modes
- Operating in coordination with manned aircraft
- Correct camera and flight settings
- Suitable weather conditions
- Standard operating procedures (SOPs)
- Risk management
- Liability
- Staying current with changing laws
- Battery voltages and proper storage
- Analyzing drone data
- Aircraft registration
Once you’ve verified that your drone pilot has the proper experience and credentials, you’ll want to do your due diligence and ask for references and reviews of past projects. Only then can you be confident you’re getting the most long-term value from a thermal roof inspection.
Next Steps: Getting Started with Thermal Drone Roof Inspections
Here at The Drone Life, our certified and experienced drone experts deliver high-quality commercial roof inspections that yield a reliable long-term ROI. If you don’t know the condition of your roof or need a baseline assessment, now is the time. Don’t hesitate to schedule a free consultation with one of our drone pilots today.
