This document presents a use case that outlines a problem for which several potential solutions exist. How did ABZ Innovation’s C10 washing drone solve this particular task? You’re about to see!

The problem

The subject is a building whose roof requires cleaning. According to the owner, no cleaning has been done for 10 years. During this time, significant natural contamination has accumulated—primarily moss. In addition, there are leaves, branches, and bird droppings present. The roof height is approximately 6–8 meters. The structure is old, and its load-bearing capacity is questionable, so standing on it and cleaning with conventional methods would be risky.

Common solutions

• Scaffolding could be erected around the building, allowing for thorough cleaning. However, it does not enable effective reach over the roof’s surface. Furthermore, procuring and assembling the scaffolding takes considerable time.

• A boom lift is much quicker to deploy, but renting it is expensive. It also requires a skilled operator. The moss coverage would make the surface difficult to clean.

• Industrial rope access is not viable in this case due to the weakened and aged roof structure—it would be unsafe to step on it.

• Telescopic cleaning is a relatively inexpensive and accessible solution, but it is extremely time-consuming.

The solution provided by ABZ Innovation

Regardless of the chosen method, water and electricity must be supplied on-site, meaning hose setup will always take time. The C10 drone, however, requires minimal preparation. The system can be made ready for operation in about 15 minutes.

We used tap water for cleaning, delivered from an outdoor faucet to the high-pressure unit using a standard garden hose.

Testing of the high-pressure equipment and air purging of the hose system was conducted on the ground, as always. This is essential not only for time efficiency but also for flight safety. At this point, the water flows through the high-pressure hose at 180 bar with a flow rate of 15 liters per minute.

We lifted the drone from the ground and gradually gained altitude. This allowed us to guide most of the high-pressure hose onto the roof with the help of the drone. Once positioned, we reactivated the high-pressure unit.

Using a tilted 40° spray nozzle, we began approaching the highest point of the designated roof plane and started loosening the moss. While flying, we cleaned the surface using a 60–100 cm wide water stream in a top-down scanning pattern.

The greatest challenge was not loosening the moss but removing the soaked and softened layers from the roof. One key factor that significantly improved efficiency was moving the drone along its vertical axis. The cleaning power directly influenced the drone’s flight speed.

Thanks to this method, we successfully cleaned a roof surface where traditional methods would have essentially failed.

Results

• Cleaned area: 550 square meters

• Time required: approx. 3 hours

• Contamination type: thick, 10-year-old moss layer

• Chemicals used: 0 liters

This type of cleaning is far from uncommon—over time, moss formation threatens nearly every roof.