How to measure a lot: parcel boundary, corners, area and official survey
Lot measurement needs more care because boundaries often relate to buildings, roads and legal records.
Field takeaways
- Parcel reference, occupation boundary and official boundary must be separated.
- Phone GPS is approximate.
- Corners and stake-out need professional control.
- KML/DXF can be reference data.
- MapLab Survey organizes notes, measurements and exports.
The first question of a plot survey
What are you measuring: the deed parcel area, the current use area, the fence or wall line, or the building setback? Those are four different lines on the same plot, and a measurement taken before answering produces arguments. Write one sentence before measuring: "The purpose of this measurement is X." Every number in the report hangs off that sentence.
The field flow, step by step
Open the parcel KML as a reference layer. Measure the existing fence, wall, road or building trace on its own layer — never mix your measurement into the reference. Record corners one by one and photograph the ambiguous ones. Read area and perimeter from the app, and note the areas of the two different lines (deed reference versus use line) separately.
What accuracy to expect
The phone's own GPS works at metre level — enough for orientation, preliminary checks and mapping the use line. Where centimetres matter, a Bluetooth RTK receiver pairs to the same app and the same flow; the hardware makes the difference. Saying which accuracy you measured with belongs in the report as much as the result does.
When boundary and use disagree
A fence can sit metres inside or outside the deed line; this is common and by itself proves nothing. The job is to show both lines on one map and report the difference in metres. Interpretation and legal consequence come from the authorised process, not from the person measuring.
The official boundary
These measurements serve reconnaissance, checking and decision support. Survey for registration, subdivision and merger are licensed surveying work. The app accelerates the field half of that job; it does not replace the signature half.
Try these steps on your own phone.
MapLab Survey handles RTK/GNSS point capture, drawing, area and volume calculations and coordinate conversion, then exports to DXF, KML/KMZ, GeoJSON, Shapefile, GeoPackage, NCZ or CSV. Capture, calculation and export work offline. Live NTRIP corrections and online basemaps need a connection.
Frequently asked questions
Can a phone measure a lot?
Approximately, yes.
How are lot corners found?
With authorized survey control.
Is parcel KML official boundary?
Not by itself.
How does MapLab Survey help?
It organizes reference and field records.
Technical references
The field guidance in this article is aligned with the technical and official references below.
Related: Finding parcel corners · Parcel query on phone · Parcel area difference · MapLab Survey