An annual diagnosis: infrared thermography, AI classification of 13 defect types and a building health score — completed in half a day with no scaffolding, tracked year over year to build the building's medical record. Assessed per building condition, with a formal proposal after the on-site assessment.
Three to five typhoons a year, 59% of housing stock over 30 years old, and fewer than a thousand qualified surveyors nationwide. Survey prices span a 45× range, and buildings are surveyed once every five to ten years.
Taiwan now has more than 5.54 million homes over 30 years old — 59% of the national housing stock. In Taipei City the figure reaches 73.8%.
Taipei has required 913 commercial-district towers to complete their first facade safety filing by the end of 2026, but there are only around 800 qualified surveyors nationwide — and Taipei alone has 4,393 buildings on the register.
Manual tapping survey is quoted anywhere from NT$35 to NT$1,574 per square metre — a 45× spread. A single building costs NT$150,000–400,000 to survey, scaffolding takes one to two weeks, and it happens once every five to ten years.
The years in between are a blind spot — while three to five typhoons a year keep accelerating the deterioration.
Sources: Ministry of the Interior real estate information platform · Taipei City Building Administration · CNA, December 2023
Nobody has a full physical once a decade. Neither should a building.
Most "AI facade inspection" on the market is a general-purpose model pointed at a wall. GDS built a multi-stage detection architecture in-house: a segmentation model trained on Taiwanese buildings finds the defects, a multimodal large model reviews them, and material-aware reading strips out false positives — collapsing the work of finding problems from days to hours. Every site's review results feed back into training, so the more we fly, the better the models understand Taiwanese buildings.
68,000+ facade defect images · instance segmentation · 13 fine-grained classes
Trained on local finishes and their failure modes — tile, split-face brick, exposed-aggregate render, painted render — and tuned for high recall: better to over-report and let the review layer filter than to let a high-risk defect slip past the first pass.
High-resolution tiled inference + cross-tile geometric merging
A crack often occupies a thousandth of the pixels in a frame and vanishes on downscaling. We cut the 48MP image into overlapping tiles, run each at full resolution, then merge — so hairline cracks survive.
Segmentation model for precise location × multimodal large model for semantic voting
Every detection is independently reviewed by a model with visual reasoning: is that a structural crack, or an expansion joint, a water stain, a window-frame shadow? Coordinates come from the expert model, semantics from the large model's vote — two AIs built on different principles checking each other, which drives false positives sharply down.
Identify the finish first, then apply material-specific defect rules
A tile joint is not a crack; sealant is not water ingress. The pipeline determines the elevation material first — tile, exposed aggregate, paint, curtain wall, fair-faced concrete — then reads defects accordingly, so surface texture is not mistaken for damage.
Automatic thermal ↔ visible geometric registration + per-pixel temperature recovery
Hollowing is invisible from outside but not to a thermal camera. Thermal imagery is registered automatically onto the high-resolution visible coordinate frame with per-pixel temperature recovered — so hollowing is not judged by looking at a colour, but on quantifiable ΔT evidence.
Where public safety is involved, AI never removes a finding on its own
For classes that can fall and injure — spalling, bulging, delamination, exposed rebar — automation may only offer an opinion; it has no authority to dismiss. The final determination is made on site by an inspector recognised by the Department of Urban Development, with the full review trail retained.
Taiwan sees three to five typhoons a year. Every one of them tears, penetrates and repeats.
Force 10+ winds work at ageing joints and loosened tiles.
Rain enters cracks, accelerating rebar corrosion and widening hollow areas.
40°C summers and 10°C winters pull joints apart year after year.
We calculate a single 0–100 score for each building, weighted across five dimensions and tracked annually — so you see the trend, not just a snapshot.
Continue annual tracking
Monitor priority areas
Schedule remediation
Address as a priority
Act immediately
Tracked every year, the health score shows you the trend rather than a single snapshot.
Manual hammer-tapping survey spans a 45× price range. These are public figures:
| Item | Per m² | Source |
|---|---|---|
| Building Administration minimum reference | NT$35 | Taipei Building Administration (window-cleaning gantry tapping) |
| Building Administration maximum reference | NT$1,574 | Taipei Building Administration (rope access tapping + removal + waterproofing) |
| City government surveyed market rate | NT$150–300 | Department of Urban Development (typical vendor quotes) |
| Highest actual case on record | NT$1,574 | CNA, December 2023 (councillor's review of filed cases) |
| Item | Full manual survey | Drone168 annual health contract |
|---|---|---|
| Frequency | Once | Once a year, compounding |
| Trend tracking | None | Year-over-year timeline and trend |
| Typhoon comparison | None | Preferential terms on extra surveys for contract clients |
| Data retention | Paper report | Permanent access on the cloud platform |
| Cost assessment | Only known after measuring on site | Tiered, with a proposal after the on-site assessment |
One aircraft carrying visible-light imaging, infrared thermography, laser ranging with RTK, and onboard AI — a whole building scanned in half a day.
24 mm wide + 70 mm medium + 168 mm tele, 112× hybrid zoom
Resolves a 0.3 mm crack at 10 m, and reaches parapet and signage-base detail.
VOx 640×512 → 1280×1024 super-resolution, ±2°C accuracy
Post-sunset full-elevation scanning, detecting tile hollowing invisible to the eye.
1,800 m ranging, centimetre-level GPS
Every defect carries precise 3D coordinates, so year-over-year comparison lands on the same spot.
Open to third-party model deployment
Flags suspected defects in flight and automatically captures them at higher density.
From site survey to timeline archiving, with flight operations completed in half a day and dual review by AI and qualified personnel.
An engineer attends to assess site conditions, plan the flight path, file the CAA flight application, and confirm ground safety control for people and vehicles.
Systematic scanning of the full envelope with the M4T to written procedure, in four stages: panoramic 3D model → visible-light detail survey → infrared thermal hollowing scan → close capture of suspect areas.
The AI processes the full image set in batch, flagging cracks, hollowing, spalling, water ingress and surface ageing — five defect families — and calculates the building health score (0–100).
An inspector recognised by the Department of Urban Development attends, reviews the AI annotations, confirms the priority areas and signs off.
A complete PDF health report: defect schedule, GPS positions, severity grades, health score and maintenance recommendations. The format complies with Taipei City's facade safety diagnosis and declaration regulations and can be used for statutory filing.
Everything is uploaded to the Drone168 platform to build the building's health timeline. At the next survey the system compares automatically, flagging what is new and what has worsened.
The regulation requires diagnosis and sign-off by qualified professionals — not any particular inspection tool. Here is how Drone168 is set up:
Authorises qualified professionals to select the inspection method by professional judgement.
Specify the qualifications of diagnostic personnel; they do not mandate exhaustive manual hammer tapping.
Infrared thermography combined with drone survey achieved 90% accuracy in identifying tile delamination.
Every AI annotation → human review by the inspector → signed confirmation, with timestamps and an operation log retained throughout and no way to alter them after the fact.
Japan, Singapore and Hong Kong moved first; Taiwan's National Land Management Agency is reviewing it. Drone168 is built to the Japanese model, ready for formal regulatory recognition.
The Ministry of Land, Infrastructure and Transport formally recognised drone infrared survey as equivalent to conventional hammer tapping.
Published TR 78:2020, the world's first technical standard for drone facade inspection.
Drones adopted under the Mandatory Building Inspection Scheme, with HK$6bn subsidising 5,000 buildings.
Taiwan's National Land Management Agency is reviewing whether to bring facade finishes into the national building safety declaration regime. Drone168 is built to the Japanese model, ready for formal recognition in Taiwan.
From ageing residential communities to public buildings, drone facade health checks are safe, quick and quantifiable — and produce a report usable directly for statutory filing.
Residential communities over 30 years old (the group Taipei City requires to file), regular survey of ageing tiled facades, and the evidence base for a management committee's annual maintenance plan. The three-year contract suits communities that need continuous tracking.
Xinyi District offices, large shopping centres, hotels. Property managers can contract across multiple buildings at portfolio terms.
Government agencies, schools, hospitals. Aligned with Ministry of the Interior public safety inspection and local government filing requirements.
Written to the format of Taipei City's facade safety declaration regulations, ready for a qualified inspector or diagnostician to sign off.
Want to go deeper on facade health checks, the filing rules, or infrared thermography? These pieces build the context.
Common questions about our annual facade health check and three-year contract. Reach out for anything else.
Diagnosis is the first step of the Facade Asset Health Program. After an on-site assessment we issue a formal proposal — a single survey or an annual health contract — assessed from facade area, building age, cladding material and elevation complexity. The choice is then yours.
Want to know what condition your facade is in? Start with an asset assessment
Leave your building details and we'll arrange an on-site assessment and walk you through how the health program works