Determine how a jurisdiction measures fence height on sloped ground or atop a retaining wall.

Steps

1. Confirm the local code's method for measuring fence height on sloped ground — common approaches include measuring from average grade at the fence line, from the higher adjacent grade, or per-post as it steps down a slope; there is no single national default.
2. Check whether the jurisdiction requires a stepped/racked fence panel design to track slope changes versus permitting a straight top with a growing gap at the low end.
3. When a fence sits atop or adjacent to a retaining wall, check whether the code measures combined wall-plus-fence height as one structure for zoning purposes rather than treating the fence as its own independent height allowance.
4. Confirm any setback-from-top-of-wall requirement, since some jurisdictions require the fence to sit back from the wall face rather than directly on the wall edge.
5. Get a written interpretation from the local zoning/building official for any borderline slope or wall-top fence condition before construction.