Drone (UAS) façade inspection support.
High-resolution UAS imagery of the building envelope to support the 100% visual sweep component of a PFI cycle — produced as elevation-indexed photographs and, where useful, georeferenced orthomosaics for defect mapping.
Where drones fit into a façade inspection
An unmanned aircraft system (UAS, commonly called a drone) is an access tool, not an inspection authority. Used well, a UAS can capture every square metre of a tall building's façade in a fraction of the time that ground-based photography would require, at a resolution that supports defect identification — and from angles that ground photography cannot reach.
Under Singapore's Building Control (Periodic Inspection of Buildings and Building Façades) Regulations 2021, the 100% visual inspection of a façade is to be carried out using photographic cameras and equivalent methods. A UAS-mounted camera is one practical way of delivering that visual sweep on buildings where ground-based or BMU-based photography is impractical due to height, geometry or surrounding access.
What a UAS does not do is replace the close-range component of an inspection. A 10% close-range physical inspection of each elevation — using probing tools, borescopes or scanning equipment — still has to be done by a person at touchable range, under the Competent Person's direction.
What a drone façade survey produces
Elevation-indexed photo set
Systematic overlapping photographs of each elevation at planned distances, indexed by face and zone. Used as the primary 100% visual sweep record for the CP's report.
Orthomosaic of each face
Where planned and accepted by the CP, photogrammetry produces a flattened, true-to-scale image of each elevation. Defects can be annotated digitally onto the orthomosaic, providing a clear locator drawing.
Defect close-ups
Targeted close-up imagery of zones flagged during the overview pass — supporting the CP's decision on where to direct the 10% close-range physical inspection.
Hard-to-reach details
Underside views of canopies, soffits, parapet caps and inset balconies — geometry that ground-based or BMU-based cameras cannot easily cover.
What drones are good at — and not
- Good for: overall condition record, defect-pattern mapping, hard-to-reach geometry, before-and-after comparison shots between cycles, supporting the 100% visual sweep.
- Less suitable for: any defect that requires touch — hollow tile detection, sealant adhesion check, probing of soft render, borescope work behind cladding return edges. These remain in the close-range scope.
- Not a substitute for: the CP's certification, the 10% close-range physical inspection, or the structured site-safety regime around work-at-height activities adjacent to the building.
Regulatory considerations in Singapore
UAS operations in Singapore are regulated by the Civil Aviation Authority of Singapore (CAAS) under the Air Navigation Act and the relevant CAAS rules on unmanned aircraft. Depending on the operation, the following may apply:
- Operator and Pilot registration with CAAS where the aircraft weight, location or operating profile requires it.
- Activity Permit for UA flights in restricted airspace, near sensitive infrastructure, or otherwise outside the scope of a standard recreational flight.
- Operator Permit for organisations carrying out commercial UA operations of certain classes.
- No-fly zones around airports, certain government installations and other restricted areas — checked before every job.
- Building owner permissions and adjoining-property considerations for any close-range flight near a façade.
The applicable permits depend on the equipment, the operating area and the operating profile. We confirm the current requirements with CAAS before booking flight time. Where the building site falls in a restricted area or near sensitive infrastructure, a UAS approach may not be appropriate and we will recommend a ground- or BMU-based alternative.
UAS flight approvals and flight timing are subject to the prevailing CAAS framework and, in some locations, additional clearance from RSAF or other airspace and security authorities. Approvals and timing can be subject to last-minute restrictions, cancellations or rescheduling due to airspace activity, security events, weather or proximity to sensitive infrastructure.
We do not promise guaranteed drone availability or fixed approval timelines for any site. UAS is always planned with a non-UAS access fallback — rope access, gondola, MEWP or scaffold — so that the inspection programme can proceed if a flight is restricted or rescheduled.
Site-safety considerations
UAS operations adjacent to occupied buildings carry their own safety regime — separate from, and additional to, the work-at-height regime that applies to rope-access or gondola crews. Our flight plans take into account:
- Exclusion zone on the ground beneath the flight path, with ground crew managing pedestrian and vehicle exclusion.
- Battery management, return-to-home conditions and forced-landing zones.
- Weather windows (wind speed and gust limits, rain, visibility) and abort criteria.
- Coordination with the building manager on resident notice, exterior camera positioning and any privacy considerations for the imagery captured.
How we work with your CP and BMU/access plan
The UAS survey is typically planned as one component of the field programme — sequenced before the close-range work so that the CP can use the UAS imagery to direct the close-range drops or trails efficiently. We deliver the UAS imagery to the CP in a structured folder layout indexed by elevation and zone, with raw files preserved alongside the processed orthomosaic where one has been produced.
Drone / UAS operations on this site are described as access and imaging support. Approval to use equivalent methods, technology or equipment for visual and close-range inspection under the PFI regulations rests with the Commissioner of Building Control on application by the appointed Competent Person.