Calculator / Decision example
Edging stock length does not specify its connectors
Written for this calculation decision · reviewed October 12, 2026 · TwoCut.
Start with the continuous border
A rectangular 10 × 6 ft bed needs 2 × (10 + 6) = 32 ft of border. At 10% buying allowance the stock budget is 35.2 ft. Generic 8 ft metal sections round to five pieces, or 40 ft purchased. Those eight excess feet combine the allowance with whole-piece rounding; they do not represent eight feet of installed border.
Fixing intervals and product kits are separate questions
At a maximum 2 ft spacing, the geometric rectangle model gives 16 fixing positions. A real section may contain attached stakes, require overlapping joints, use special corner pieces or need extra support in loose soil. “Five sections and sixteen spikes” is therefore a model output, not a bill of materials for an arbitrary branded kit.
Compare two purchasing alternatives
A 40 ft flexible roll could cover the stock budget without section joints, but still requires its own corner and anchoring instructions. Metal sections may hold a chosen profile more firmly while adding connectors and cut ends. Neither option is selected automatically: check usable coverage after overlaps, the intended curve radius and the product’s supplied hardware.
Basis and error sources
The perimeter and upward rounding are basic geometry. Colmet attached-stake edging illustrates why hardware depends on the product rather than on a universal spike spacing. For an irregular border, enter its measured total instead of treating it as this rectangle. Buried obstacles and cut losses remain site measurements. Changing the allowance does not substitute for a connector specification.
Compare the purchasing decision
| Alternative | Arithmetic | Buying implication |
|---|---|---|
| 8 ft metal stock | 5 pieces / 40 ft | Connectors and product fixings checked separately |
| 40 ft flexible roll | 1 roll / 40 ft | Confirm corner treatment, overlaps and anchors |
These alternatives use the stated model rather than field measurements. A lower headline quantity is useful only when the product inputs and required cuts are correct.