Fullness Types
While dart manipulation redistributes existing fabric to shape around body contours, adding fullness increases the actual surface area and circumference of a pattern piece to create volume, drape, flare, or decorative gathering.
Fullness is introduced into a basic sloper using variations of the slash-and-spread technique.
1. Parallel (Equal) Fullness
Parallel fullness is used when an equal amount of excess fabric is needed across the entire length of a section.
- The Draft:
- Draw parallel lines across the pattern piece from one edge to the other where you want to add volume.
- Cut completely through the pattern along these lines, separating it into individual strips.
- Place a fresh sheet of paper underneath.
- Spread the strips apart evenly by a calculated distance (e.g., 1 inch or 25 mm) between each strip.
- Tape the pieces down and trace a smooth new outline across both edges.
- The Result: Both the top and bottom seamlines increase by the exact same measurement.
- Common Uses: Peasant sleeves, gathered dirndl skirts, smocked bodices, and uniform pleating.
2. One-Sided (Flared / Tapered) Fullness
One-sided fullness adds width along a single edge while maintaining the exact original measurement on the opposite, hinged edge. In the illustration below, the bust dart was first moved to Center Front, and then 1.5" (38 mm) of added fullness was spread at each of three additional slash points. When these spread sections are gathered and the front panels are sewn together, it creates soft center-front shirring. The grey triangles highlight the additional fabric volume.
Bust Dart Moved to Center Front
One-Sided Fullness Added to Center Front at 3 Points
- The Draft:
- Draw parallel lines across the pattern piece from the edge requiring fullness directly to the opposing seamline.
- Cut along these lines, leaving a small paper hinge at the pivot edge.
- Place a fresh sheet of paper underneath.
- The slashes are fanned open into triangular gaps.
- Tape the pieces down and trace a smooth new outline across the fanned edge.
- The Result: The hinged edge remains at its original finished dimension, while the fanned edge expands significantly.
- Finishing the Edge:
- Smooth Flare: The fanned edge is left ungathered, allowing the excess to fall into fluid, free-hanging drapery (such as an A-line skirt or flutter sleeve).
- Gathered / Pleated: The fanned edge is gathered or pleated back into a smaller adjoining band or cuff.
Gathered Center Front Bodice Sewn
Choose the edge for fullness on sleeves:
- Puff Cap Only: Slash from the cap down to the hemline, leaving paper hinges at the hemline. Spread the top cap apart like a fan to create extra length and gathering room over the shoulder while keeping the cuff width unchanged.
- Puff Wrist Only: Slash from the hem up to the cap, keeping hinges at the sleeve cap. Spread the bottom wide to add fullness while keeping the armhole fitting line identical.
3. Unequal Fullness
Unequal fullness occurs when both edges are expanded, but one edge requires significantly more volume than the other. The pattern is cut completely through, and each slash line is spread with a wider gap on one side and a narrower gap on the other.
Grainline & Truing
- Preserving Grainline: When spreading parallel sections, align the center section or primary grainline parallel to the fabric straight grain. For radial/flared cuts, place the grainline through the center axis so drape falls symmetrically on both sides.
- Truing the Seamlines: Spreading sections creates jagged, stepped edges along seamlines and hems. Blend and true these edges with a smooth, continuous curve before adding seam allowances.
Calculating Fullness
It can be difficult to know how much you need to add when you are flaring or adding fullness to your drafts. Most drafting books are vague with instructions to "spread as desired".
Determining how much fullness to add through slashing and spreading depends on the desired volume and the fabric's drape.
Industry & Reference Benchmarks
| Fullness Ratio | Multiplier Formula | Best Fabric Pairing | Common Applications |
|---|---|---|---|
| Slight / Soft Ease | 1.25 - 1.33 | Heavy linen, denim, wool flannel | Eased sleeve caps, subtle skirt yokes, back shoulder gathers |
| Standard Gather | 1.5 | Medium-weight cotton, linen, silk shantung | Bodice waist gathers, bishop sleeve cuffs, dirndl skirts |
| Full / Classic Volume | 2 | Poplin, lawn, chambray, rayon, challis | Puff sleeves, ruffled collars, peasant blouses |
| High Drama / Sheer | 2.5 - 3 | Chiffon, organza, batiste, tulle | Historical ruffs, multi-tiered maxi skirts, tiered petticoats |
Classic texts generally advise keeping individual slash openings under 2" to 2.5" (50 mm to 65 mm) each. Spreading fewer slashes at 5" (125 mm) each creates sharp, angular seam distortions that are difficult to true smoothly; using more slashes distributed evenly produces a clean, continuous curve.
The Formula
- Measure the original seam line length.
- Multiply the original length by your target ratio to get the target length
- 10" x 2 = 20"
- 250 mm x 2 = 500 mm
- Subtract the original length from the target length to determine the total added spread.
- 20" - 10" = 10" to add
- 500 mm - 250 mm = 250 mm to add
- Divide the total added spread by the number of slash cuts.
- 5 Slashes: 10" / 5 = 2" spread per slash
- 2 Slashes: 10" / 2 = 5" spread per slash
- 5 Slashes: 250 mm / 5 = 50 mm spread per slash
- 2 Slashes: 250 mm / 2 = 125 mm spread per slash
Adding Fullness in PatternMaker Pro
You can add parallel, one-sided and unequal fullness to your patterns using the Add Fullness tool. It can also be used in combination with the Move Dart tool as shown in the One-Sided Fullness images above.