Plan smooth garden drapes with accurate stackback. Choose draw style, panel count, and track spacing. See results instantly and export a neat worksheet file.
1) Coverage width: coverage = rodSpan + 2×return + (overlap if center draw)
2) Flat fabric width: flatTotal = coverage × fullness × (1 + allowance%)
3) Stackback estimate: stackbackTotal = (flatTotal ÷ compressionRatio) × carrierFactor + hardwareAllowance
4) Per-side stackback: center draw splits stackback; one-way draw does not.
| Scenario | Span | Returns | Style | Fullness | Panels | Estimated Stackback (Total) |
|---|---|---|---|---|---|---|
| Patio shade track | 96 in | 4 in | Ripplefold | 2.0x | 2 | ~16–20 in |
| Greenhouse privacy drape | 84 in | 5 in | Pinch pleat | 2.5x | 2 | ~20–26 in |
| Shed door light blocker | 60 in | 3 in | Grommet | 2.0x | 1 | ~18–24 in |
These examples are typical estimates. Vendor specs, fabric bulk, and lining can change stackback.
Stackback is the parked width of drapery when fully open. For outdoor kitchens, pergolas, and greenhouse doors, reserving enough wall space prevents fabric from blocking airflow or light. Many projects target a minimum clear opening of 85–95% of the rod span after stacking, depending on use.
Start with rod span, add two returns, and add overlap for center draw. Example: a 96 in span with 4 in returns and a 3 in overlap yields 107 in of coverage. At 2.0x fullness, the flat width becomes about 214 in before allowance. Adding a 5% allowance raises that to roughly 225 in for hems, turnbacks, and measuring error.
Fullness increases folds and improves privacy, but it also increases stackback. Practical planning ratios often fall between 2.0x and 2.5x for lined drapes and 1.8x to 2.2x for light sheers. Ripple-style headers compress efficiently, while grommets and rod pockets usually compress less. As a check, dividing flat width by a compression ratio of 3.0 produces a starting stackback.
Traverse carriers, masters, and end returns add fixed bulk. Tighter carrier spacing may add 3–10% to stacked width because more hardware accumulates at the ends. If your supplier publishes a “stackback per panel” spec, enter it through the custom allowance fields to match real components.
The calculator outputs total stackback, per-side stackback, and a recommended wall-space target with clearance. If available wall space is short, reduce fullness, split into more panels, switch to a higher-compression header, or stack to one side. A longer track can also move stacks past the opening edge when structure allows. Export CSV for quoting and PDF for on-site installation notes.
Aim for stacks that keep at least 85% of the opening clear. On busy walkways, prioritize smaller stackback by using efficient headers or moderate fullness.
Yes. Lining and interlining increase bulk and reduce compression. If you use heavy lining, add extra hardware allowance or use a lower compression ratio for a safer estimate.
Center draw splits stackback across both sides. One-way draw puts the full stack on one side, which helps if only one side has enough wall space.
For privacy and richer folds, use 2.2x–2.5x. For lighter garden sheers or budget builds, 1.8x–2.1x often looks clean while limiting stackback.
More carriers mean more hardware collecting at the stack point. Smaller spacing can slightly increase stackback, especially on wide spans with multiple panels.
Use it as a planning summary for measurements and assumptions. Always confirm final stackback against manufacturer specs and test a sample panel if fabric thickness is unknown.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.