Measured project / purchasing workbook
Irregular Outdoor Footprint Measurement Tool
Measure convex footprints or non-overlapping triangles, reconcile exclusions and diagonal checks, and record a conservative area uncertainty range.
Measured project workbook
Irregular outdoor footprint measurement
Irregular outdoor footprint measurement
What this worksheet covers
Keep named corners, sufficient coordinate measurements, non-overlapping triangles and exclusions on one field sketch, with a conservative measurement range.
This is a local material-area measurement, not a boundary survey or legal determination. Area can inform bulk material or finish purchasing. Importing area does not create a supported deck or paver piece layout. Curves require an explicitly labeled straight-segment approximation.
Import a saved measurement
Select a source, then an existing field with the same measurement unit. Add region or station rows first when needed. Confirm physical meaning and datum; importing a number does not approve a design or replace the rest of the required measurements.
Enter the measured layout and selected product information, then calculate. Exact schedules and a drawing appear here.
Calculation reference
Method and limits
Measured local coordinates produce area and boundary length. The uncertainty calculation describes entered coordinate error; it does not turn approximate curves into survey evidence.
Convex corners or measured triangles
Choose one ordered strictly convex polygon, or up to 30 non-overlapping measured triangles. Do not fill both tables. Up to ten convex exclusions must lie inside the measured footprint and must not overlap. Each polygon uses the absolute shoelace area; exclusions subtract from the included sum. Shared triangle seams cancel when the material boundary is reconciled, while exposed exclusion edges remain boundary.
polygon area = |Σ(xᵢyᵢ₊₁ − xᵢ₊₁yᵢ)| / 2; net area = included − excluded
Coordinate uncertainty
For entered per-coordinate error e, each polygon contributes e/2 × Σ(|y_next − y_previous| + |x_previous − x_next|) + vertex count × e² to a conservative area bound. Included and excluded bounds are added. The lower net area is clamped at zero; the upper area adds the bound. The perimeter bound adds 2√2 × e for each entered corner. These bounds are not statistical confidence intervals.
An area record, not a material layout
Curves remain acknowledged straight-chord approximations; the entered coordinate-error bound does not include curve approximation error. This tool applies no waste or package rounding and recommends no material purchase. Exporting its area does not create supported board seams, paver cuts, layer depths or a surveyed boundary.
Arithmetic checked against the current calculation source on 1 October 2026. Product instructions remain the exact records entered in this worksheet; recording a source is not external approval.
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