MEASUREMENT CHECK
Roof Pitch Calculator: Reference Point Check
Measure rise and horizontal run from the same labelled reference points. A roof pitch calculator can only transform the pair supplied; it cannot correct a pair assembled from different locations.
Keep both measurements on one triangle
A vertical rise and a horizontal run describe one right triangle. Mark the ridge reference point and the matching eave-side reference point before recording either value. If either point changes, record a new pair.
Name the ridge and eave reference points.
Keep rise and run on the same plane.
Store labels, units, and the result together.
Can I mix a rise and run from nearby points?
No. Use a pair from the same identified triangle; nearby points can describe a different roof plane or baseline.
Geometry record only.
This check improves input traceability. It does not verify construction or approval.