How much extra fabric do I need for nap?

Typically 10–20% extra depending on the garment complexity. Simple projects like cushions need about 8–10% more, while jackets and coats with many pattern pieces may need up to 20–25% extra fabric.

What is a nap layout?

A nap layout means all pattern pieces are placed in the same direction on the fabric. This is essential for fabrics with a nap (like velvet or corduroy), a sheen direction (satin), or a one-way print so the fabric looks consistent across the finished garment.

How do I tell which direction the nap runs?

Stroke the fabric — velvet and corduroy feel smooth in one direction and rough in the other. For satin, tilt the fabric under a light to see the sheen direction. For prints, the motif direction is usually obvious. Cut with the nap running downward for a richer colour.

Does fabric width affect the nap allowance?

Not directly, but narrower fabric (90–112cm) already needs more yardage for any layout, and the nap constraint makes efficient piece placement harder. The percentage extra stays similar, but the absolute amount of extra fabric is greater for narrow bolts.

SewCalcs

Nap Layout Calculator \u2014 Extra Fabric for One-Way Layouts

Calculate extra fabric needed for one-way, nap and directional pattern layouts.

Standard Fabric Needed

Fabric stated on pattern for without-nap layout

Fabric Width

Bolt width of your fabric

Fabric Type

Type of napped or directional fabric

Garment Type

Type of project being made

Pattern Pieces

Number of pattern pieces to cut

Fabric Price (optional)

Price per metre for extra cost estimate

How We Calculate This

When all pattern pieces must face the same direction, you lose the ability to flip pieces for efficient nesting. This calculator estimates the extra fabric needed.

The formula

Nap fabric = Standard fabric × (1 + Extra %)

The default extra percentage is based on garment type:

Simple project: ~8%
Trousers/skirt: ~10%
Blouse/shirt: ~12%
Dress: ~15%
Jacket/coat: ~20%

A small additional factor is applied for patterns with more than 8 pieces, as layout efficiency decreases with more pieces.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Always verify quantities before cutting or purchasing fabric.