Typical scenarios within this site’s subject: questions to ask, materials to prepare and points that can be examined.
Typical scenarios
If fill after site grading is calculated from two digital surfaces, the difference may include changes in the underlying data. In this hypothetical situation the earlier survey misses a site edge, the later one includes a temporary stockpile, and the software uses different boundaries without showing interpolated areas.
Typical scenarios
An area discrepancy may be described as a boundary change. Suppose coordinates were copied from several files, vertex order was unchecked and software accepted angular values without a stated reference system, then labelled the result square metres.
Typical scenarios
If paving is followed by pooling, the neighbouring plot may be blamed. Suppose paving and gate-threshold levels changed, old heights survive only on a drawing and puddle photos show neither rain-time flow nor ditch condition.
Typical scenarios
A satellite basemap may lead users to mistake a roof edge for a wall. An on-screen distance may differ from a tape measurement along the fence, without checking image origin, positioning accuracy or whether the fence follows the registered boundary.
Typical scenarios
If a proposed passage is shown where a neighbour considers their plot to lie, the source boundaries must first be established. An old plan and the existing fence may reflect different information and periods.
Typical scenarios
If comparison of an old plan and a new diagram shows a boundary shift, this does not necessarily mean a fence was moved or neighbouring land occupied. Documents may use different coordinate systems, scales and point-position accuracies. Each diagram's origin and suitability for alignment must first be established. Overlaying pictures without checking source data can create a convincing but unreliable impression that boundaries overlap.
