Drone, rope access, gondola, platform or pole: which one for your building?
There is no single best way to clean a façade. We use three of the five methods below ourselves and we say no to the drone when another tool does the job better. Here is how we choose.
Short answer: a tethered drone is the fastest option on large, tall, flat or curved surfaces with a clear ground area below, and it keeps everyone on the ground. Rope access remains the right choice for detail work on complex façades. A building maintenance unit (gondola) is efficient where it exists and reaches every façade. A water-fed pole wins below about 17 m. An aerial platform is for detail work and places the drone cannot fly close to. Most of our jobs combine two methods.
| Method | Best for | Speed | People at height | Main limits |
|---|---|---|---|---|
| Tethered drone | Large glass and cladding surfaces, curved façades, inner courtyards, roofs, solar arrays | 500–800 m²/h on suitable surfaces | None during application | Wind, rain, permits, ground perimeter, encrusted dirt needing a brush |
| Rope access | Detail work, complex façades, inspections by hand | Slow on large surfaces | Yes, technicians on ropes | Anchors needed on the roof, weather, working-at-height risk, workers in front of rooms |
| Gondola (BMU) | Towers that already have one, regular glass cleaning | Medium | Yes, in the cradle | Only where installed, maintenance and downtime, does not reach every façade or canopy |
| Aerial platform | Detail work, frames and joints, low and medium heights | Medium to slow | Yes, in the basket | Needs ground access and space, up to about 40 m, slow on very large surfaces |
| Water-fed pole | Ground to fourth floor, shop fronts, glass roofs over lift shafts, canopies | Fast at low height | None | Height, about 17 m maximum |
Where the drone wins
- Tall buildings without a gondola, or with a gondola that does not reach every façade.
- Curved, stepped or set-back façades that a cradle or platform cannot follow.
- Closed courtyards and atriums where nothing with wheels can get in.
- Occupied buildings: no worker hanging outside guest rooms, patient rooms or offices.
- Fragile roofs and solar arrays that must not be walked on.
- Short interventions: set-up in hours, not days of scaffolding.
Where the drone loses
- Heavy encrusted dirt that needs mechanical brushing: the pole or the platform does it.
- Frames, joints, sills, detail work: a person with a brush is better.
- Wind and rain: the drone stays on the ground.
- No safe ground area below the work zone: we cannot close a perimeter, we do not fly.
- Airport zones and restricted airspace without permission.
That is why our teams carry a 17 m carbon pole and can bring a 40 m platform. The drone does the volume, the pole and the platform do the finish.
What drives the cost
Whatever the method, five things set the price.
Access and set-up
Scaffolding and anchors cost days. A gondola costs maintenance. A drone needs a perimeter and permits. The pole needs nothing.
Hours at height
Every hour with a person on a rope or in a basket is slower and more supervised than an hour with a pilot on the ground.
Surface and dirt
Glass with pollution film is fast. Textured cladding with algae is slow. Encrusted dirt needs brushing whatever the tool.
Frequency
A building cleaned three times a year is cheaper per pass than one cleaned every three years.
Disruption
Closing a car park for a morning is cheap. Closing a hotel wing for a week is not. Night work costs more per hour but saves days.
Site constraints
Water and power on site, take-off area, airspace. We check all of this in the survey before quoting.
Comparison questions
Is drone cleaning cheaper than rope access?
Usually, on large surfaces: fewer hours, no anchors, no days of set-up. On small or detailed surfaces, rope access or a pole can be cheaper. We quote both when it is close.
Is drone cleaning safer?
Nobody works at height during application, and the ground zone is closed and controlled, with a prevention plan. The risk moves from people to equipment, which is why the drone is tethered and why we follow the Thai distance and permit rules.
Can a drone replace our building maintenance unit?
It can replace it for cleaning the surfaces the gondola reaches, and add the ones it does not. It does not replace it for glass replacement or maintenance tasks.
Can the drone clean windows from the inside?
No. Interior glass is done by hand or with a pole.
Have a building in Thailand that is hard to clean?
Send us a few photos, the address and the approximate height. We will tell you honestly whether a drone, a water-fed pole or a platform is the right tool, and whether your site could join the pilot program.