Drone, rope access, EWP or scaffold: choosing an access method for exterior cleaning

The methods at a glance

Scaffold

Scaffold gives a stable working platform across a whole elevation, which is why it remains the right choice when cleaning is part of a larger job such as facade repairs, sealant replacement or repainting. For cleaning alone it is rarely economic. Hire, erection and dismantling dominate the cost, the building is wrapped for weeks, and balconies, windows and frontages are blocked for the duration.

Elevated work platforms

Boom lifts and scissor lifts are quick to set up and suit low to mid-rise buildings with firm, level ground beside each elevation. Their limits are reach, ground conditions and footprint. The machine needs hardstand, often occupies car parking or a footpath, and setbacks, landscaping or basement slabs can stop it getting close enough. Boom-type platforms with a boom of 11 metres or more also need an operator who holds a high risk work licence.

Rope access

Abseil technicians can reach almost any elevation and can do hands-on work that a drone cannot, such as scrubbing heavy staining, resealing or inspecting at arm's length. The trade-offs are that people work at height on every drop, roof anchors must be inspected and certified before use, the area below each drop is closed off, and progress is one drop at a time. Specialist crews can also carry booking lead times.

Swing stages and building maintenance units

Some towers were designed with a permanent building maintenance unit or davit system. Where one is installed and certified, it is a practical way to reach glazing. Where there is none, rigging a temporary swing stage adds engineering, certification and time. Either way, people still work in a suspended cradle beside the facade.

Drones

A cleaning drone carries the spray to the surface while a two-person crew controls it from the ground. Nobody works at height, nothing is fixed to or loaded against the building, and most buildings are finished in days rather than weeks.

The method has clear limits. It does not suit heavy mechanical staining, graffiti or coating removal, ground-level hardstand, internal atria, or sites in airspace where approval cannot be obtained. Wind sets an operating limit on every flight, and CASA's separation rules mean the ground below the work has to be managed. Our CASA guide covers those rules.

Combining methods

Sometimes the best answer is a mix. A drone can clean the upper elevations, roof and glazing while a ground-level crew cleans shopfronts, awnings and paving. On a building due for repairs, a drone clean beforehand shows the true condition of the facade before anyone commits to scaffold.

How to choose

• Is the job cleaning only, or cleaning plus repairs? Repairs usually need hands-on access.
• How tall is the building, and how much ground is there beside each elevation?
• Is the building occupied or trading, and how much disruption can it take?
• Is the soiling organic growth and salt film, or heavy staining and graffiti?
• Is the site near an airport, a helipad or other controlled airspace?
• How often does it need cleaning? Recurring cleans multiply the cost of access.

If you are not sure, send us the address. We will tell you at scoping whether a drone suits the building and, if it does not, which trade does. The cost guide explains how each choice affects the price.