Round curtain fabric widths before multiplying by drop length.
Why can a curtain order exceed finished coverage area divided by fabric width?
Use the matching calculator
Use this decision sequence
- Use the specified rod coverage and fullness to determine required sewn width.
- Use usable fabric width after the applicable seam and side-hem deductions.
- Round to full fabric widths per window before multiplying by aligned cut drop.
- Keep separately matched windows separate unless a checked cut plan proves shared use.
Keep the quantities distinct
| Quantity or assumption | How to use it |
|---|---|
| Finished rod coverage | Not the same as full fabric width demand. |
| Full fabric widths | Discrete cuts across the fabric roll. |
| Aligned cut drop | Includes supplied allowances and pattern-repeat rounding. |
Worked comparison
An illustrative 2 m rod at supplied fullness 2 requires 4 m sewn width. With 1.5 m usable fabric width, that takes three full widths. A 2 m drop plus 0.2 m allowances rounds to 2.4 m at a supplied 0.3 m repeat. Two identical windows then need 3×2.4×2 = 14.4 m of fabric before other separately specified constraints.
Check before using the estimate
Fullness and allowances are supplied specifications; this estimate does not recommend curtain styles or product handling.
All dimensions, product properties, prices and specifications in this example are illustrative arithmetic inputs. Use the values from your measured plan, selected product data sheet and supplier quote. This guide does not choose construction specifications or certify safety.
Calculation and scope checked 2026-10-04. Methods and scope.
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