Fullness Ratios: The Single Biggest Yardage Variable
Fullness is how much wider the fabric is than the window. A 36" window at 2× fullness uses 72" of fabric width. More fullness means deeper, richer folds — but also more fabric. Here is what each ratio delivers:
| Fullness Ratio | Look | Best For | Fabric for 36" Window |
|---|---|---|---|
| 1.5× | Flat, minimal gathering | Sheer curtains, budget projects | 54" wide |
| 2× | Standard, soft folds | Rod pocket, grommet, everyday curtains | 72" wide |
| 2.5× | Luxurious, deep pleats | Pinch pleat, formal drapery | 90" wide |
| 3× | Opulent, hotel-style | Floor-to-ceiling formal drapes | 108" wide |
Header Allowances by Curtain Style
The header is the extra fabric above the rod — it varies significantly by style and directly adds to your cut length:
| Heading Style | Header Allowance | Fullness | What the Header Covers |
|---|---|---|---|
| Rod pocket | 4" | 2× | Pocket casing + ruffle above rod |
| Grommet | 3" | 2× | Reinforced facing + grommet tape |
| Pinch pleat | 6" | 2.5× | Buckram stiffener + pleat tape + return to wall |
| Valance | 2" | 2× – 2.5× | Rod pocket + top ruffle |
Step-by-Step: 36"×60" Window, 54" Fabric, Each Style
Let us calculate the exact yardage for the same window with every heading style. All examples use 54" fabric (52" usable), double-fold 4" hem, and a single panel covering the full window:
Rod pocket (2× fullness, 4" header):
- Widths needed = Ceiling(36 × 2 ÷ 52) = Ceiling(1.38) = 2 widths
- Cut length = 60" + 4" hem + 4" header = 68"
- Yardage = 2 × 68 ÷ 36 = 3.78 yards
Grommet (2× fullness, 3" header):
- Widths needed = Ceiling(36 × 2 ÷ 52) = 2 widths
- Cut length = 60" + 4" hem + 3" header = 67"
- Yardage = 2 × 67 ÷ 36 = 3.72 yards
Pinch pleat (2.5× fullness, 6" header):
- Widths needed = Ceiling(36 × 2.5 ÷ 52) = Ceiling(1.73) = 2 widths
- Cut length = 60" + 4" hem + 6" header = 70"
- Yardage = 2 × 70 ÷ 36 = 3.89 yards
Valance (2× fullness, 2" header, 15" finished length):
- Widths needed = Ceiling(36 × 2 ÷ 52) = 2 widths
- Cut length = 15" + 4" hem + 2" header = 21"
- Yardage = 2 × 21 ÷ 36 = 1.17 yards
Panel Count: One-Way Draw vs Two-Way Draw
How many panels you need depends on how the curtains open. A one-way draw (stack to one side) uses one wide panel. A two-way draw (split in the middle) uses two panels that meet at the center. Each panel needs its own set of fabric widths — so a two-way draw doubles the number of panels but does not double the total yardage because each panel covers half the window. For a 72" wide window with two-way draw at 2× fullness, each 36" half needs 2 widths of 54" fabric, so you cut 4 widths total across 2 panels.
Lining Requirements
Curtain lining is typically cut to the same width and slightly shorter length than the face fabric. For standard lining (54" wide), calculate the same number of widths as the face fabric, but subtract 3" from the cut length (lining stops above the hem). For blackout lining, use the same full cut length — it should extend to the hem for maximum light blockage.
Standard Window Size Chart with Yardage Estimates
| Window Size | Rod Pocket (2 panels, 2×) | Pinch Pleat (2 panels, 2.5×) | Grommet (2 panels, 2×) |
|---|---|---|---|
| 24×36 | 4.75 yd | 5.75 yd | 4.75 yd |
| 36×48 | 6.25 yd | 7.50 yd | 6.25 yd |
| 36×60 | 7.50 yd | 9.00 yd | 7.50 yd |
| 48×72 | 9.00 yd | 11.00 yd | 9.00 yd |
| 72×84 (sliding door) | 15.50 yd | 19.00 yd | 15.00 yd |
Estimates assume 54" fabric, 4" hem, and no pattern repeat. Add 20–30% for large pattern repeats. For 108" wide drapery fabric, yardage is roughly half.
Pattern Matching on Wide Curtains
When your curtain needs multiple fabric widths seamed together (as most do), the pattern must align horizontally across the seam. For each additional width beyond the first, you shift the cut up or down by the pattern repeat until the design lines up. A 24" repeat on a 3-width curtain panel adds up to 48" of extra fabric just for matching — that is 1.33 extra yards. Large floral or geometric prints with 27" repeats on floor-to-ceiling drapes can push your yardage up by 30% or more.
Ready to calculate your own curtains? Use our interactive curtain fabric calculator — it handles fullness, header allowances, pattern repeat, and panel count automatically for all four heading styles.