Obtain the support layout before counting
Identify straight runs, corners, ends, gates and changes of level. The selected system and competent design should define line-post spacing and the required terminal and bracing arrangements.
The University of Georgia’s farm fencing publication distinguishes line supports and braced assemblies. Its regional construction examples should not be substituted for the design of an unrelated fence or soil condition.
Calculate a straight run
Assume a hypothetical 120 m straight run with an already approved maximum bay length of 4 m. The number of bays is ceil(120/4) = 30. An open straight run has 31 post positions, including both ends.
If the ends use separately designed straining assemblies, the 31 positions comprise 29 intermediate positions and two end positions. Count additional brace members according to the approved assembly; they do not appear automatically in the line-post formula.
For a 122 m run under the same assumed maximum, 30 bays would be too long. Use at least 31 bays, giving 32 positions. If the design permits equal bays, their length would be about 3.935 m. The designer may instead specify another setting-out arrangement.
Split the schedule at real changes
| Feature | Counting rule |
|---|---|
| Gate | End the adjoining run and schedule its support arrangement |
| Corner | Use the approved corner assembly, avoiding duplicate shared items |
| Terrain transition | Follow the approved straining and support detail |
| Closing bay | Record its actual length and construction |
| Brace | Count the complete assembly separately from ordinary line positions |
Do not apply “bays plus one” independently to every line on a plan and then accidentally buy the same shared corner twice. Use unique support identifiers to reconcile quantities.
Keep wire allowances separate
Post positions do not determine usable roll length or termination allowance. Calculate wire and joining components using the actual straining sections and product instructions. A route may have the same overall length but require more terminations because of gates or changes in alignment.
Do not use a quantity article as an installation tensioning procedure. Tensioned wire and support work require the selected system’s instructions, suitable equipment and a safe method.
Check the count against the drawing
List each run’s length, permitted spacing, bay count and support identifiers. Sum the unique supports, then add brace components and gate assemblies. Compare that schedule with the delivered package before sending materials to remote installation areas.
At completion, update positions that changed through approved site decisions. The resulting as-built support map is also the starting point for later repairs or extensions; it records the real configuration instead of leaving maintenance staff to infer it from average spacing.