How it works
Every result on plotdetect.com.au comes from live government data sources and satellite imagery — not static PDFs or manually maintained databases. Here's exactly where each tool gets its data, how often it updates, and what the limitations are.
Site Report
Try it →Data sources
Update cadence
Government APIs are queried live when the report runs (typically 1–2 minutes end to end). Satellite layers use each source’s own imagery cadence. DCP controls and land-use tables are updated as councils are onboarded and re-checked by weekly source monitoring.
Limitations
The development capacity figure is a computed ceiling from mapped controls — not an approval outcome, and merit assessment can produce a different result. Eligibility outcomes are subject to a development application. Layers with no data for a property say so — absence of data is not clearance. Every figure carries its source and as-at date.
Granny Flat Eligibility
Try it →Data sources
Update cadence
Planning Portal data is queried live at time of check. Aerial imagery is updated by NSW Spatial Services (typically annually). DCP controls are updated when new LGAs are onboarded.
Limitations
Structures already on the lot are identified by you from the aerial image, not found automatically. An automated scan was measured in August 2026 against human review of 56 lots across four councils: it located 14 of the 38 secondary structures a person could see, and reported a further 15 that were not there. It is not used to decide eligibility. Heritage overlays and strata restrictions may introduce exceptions. DCP setback data is available for councils with structured controls. Always confirm with a certifier before committing.
Pre-DA Site History
Try it →Data sources
Update cadence
Satellite composites are based on annual dry-season imagery (June–September, lowest cloud cover). DA records are queried live from the ePlanning Portal. Heritage overlays are updated when councils publish new spatial data.
Limitations
Satellite change detection has ~10 m resolution — small structures (sheds, fences) may not register. DA records depend on councils submitting to the ePlanning Portal. Heritage overlays cover conservation areas only, not all individual heritage items.
Development Monitor
Try it →Data sources
Update cadence
DA data is refreshed daily from the NSW ePlanning Portal. There is typically a 24–48 hour lag from lodgement to appearance in results.
Limitations
Coverage depends on councils submitting applications to the ePlanning Portal. Some councils may have incomplete records. Search radius is 500 m for the free check; monitoring alerts cover 200 m.
Conveyancing Planning Disclosure
Try it →Data sources
Update cadence
Planning Portal data is queried live. DCP provisions are updated when new LGAs are onboarded or instruments are amended.
Limitations
DCP setback controls are available for 22 LGAs. Full DCP coverage (all provision types) is available for Inner West Council. The conveyancing disclosure does not replace a section 10.7 planning certificate.
How we check our work
Every data source listed above is monitored by automated checks that run daily. If a government API goes down, returns unexpected data, or stops responding entirely, our monitoring flags it before any report is affected.
15
Data sources monitored daily
100%
Reports with full audit trail
< 2 min
Alert time on source failure
- -Every report records the exact API endpoints queried, response timestamps, and data versions used.
- -Reports with missing audit data or empty outputs are flagged automatically and withheld until resolved.
- -Source health checks probe each API for expected response structure, not just HTTP 200 status.
How results are computed
Every tool on this platform uses deterministic processing. Given the same property and the same source data, the result is identical every time. There is no AI interpretation, no language model inference, and no probabilistic scoring in the compliance pipeline.
- -Planning controls are extracted verbatim from government instruments — never paraphrased or summarised.
- -Satellite analysis uses published spectral indices with fixed thresholds, not trained classifiers.
- -Where multiple data sources cover the same property, all are shown independently — we do not blend or average conflicting values.
Where location-specific (precinct) rules come from
Some council DCP chapters apply only inside mapped areas — town centres, beachfront character areas, named sites. The boundary of each area is defined by a map figure in the adopted DCP document itself, and that figure is the authority. Council online mapping services publish machine-readable copies of those figures, which councils label as a guide only.
Before a boundary is used to match addresses, it goes through a fixed set of checks:
- -Geometry checks — the polygon must be valid, in the expected coordinate system, with area and location consistent with the adopted figure.
- -Point checks against the adopted figure — real addresses geocoded through the NSW Planning Portal, chosen from inside and outside the mapped area, must match or not match exactly as the DCP figure shows. Negative tests (addresses that must return no match) are part of the set.
- -Provenance recorded — each stored boundary records the DCP map figure it copies, the geometry source, and the date it was checked.
Where an area's boundary has not passed these checks, its location-specific rules are excluded from results and the report states that site-specific controls may exist for the property — a missing boundary is disclosed, never silently filled in. Where mapped areas overlap, the rules for every applicable area are returned. The per-property legal record of which controls apply remains a Section 10.7 planning certificate issued by the council.
What this is not
- -Not a planning certificate. These results do not replace a Section 10.7 certificate issued by council.
- -Not legal or financial advice. We present government data — interpretation requires a qualified professional.
- -Not a substitute for site inspection. Satellite and spatial data cannot capture every on-ground condition.
- -Not exhaustive. Where data is unavailable for a property, the result states “unavailable” — absence of data is not clearance.
A note on accuracy
All results on this platform are indicative — they are starting points for due diligence, not formal planning determinations. NSW planning controls change frequently, and no automated system can substitute for a qualified town planner or building certifier reviewing your specific situation. We cite every data source so you can verify results directly.