How much fabric for an umbrella cut frock?

What umbrella cut means

The skirt is cut as part of a circle, like the cover of an open umbrella. The small inner curve is sewn to the bodice and the large outer curve becomes the hem. Because the shape itself supplies the flare, the join sits smooth, with no gathers, and the hem falls in soft waves.

That is different from a kalidar, where the fullness comes from long straight-sided panels, and from a gathered frock, where a wide rectangle is pulled in at the seam. Our kalidar frock guide covers the panelled kind. Tailors also use “umbrella” loosely for any very full hem, so a photo helps to show which you mean.

Why length and width decide the amount

Think of the skirt as a ring. Its radius is a small allowance for the waist curve plus the skirt length. For a full circle the waist allowance is the seam measurement divided by 6.28; for a half circle, divided by 3.14. Take a seam of 32 inches (81 cm) under the bust and a skirt of 34 inches (86 cm): the full-circle radius is about 5 inches plus 34, plus a hem, so roughly 40 inches (102 cm).

A full circle is normally cut as two half circles, and each half needs a piece of cloth twice the radius long and one radius wide. Here that is about 4.1 metres for the skirt, and the hem measures over 6 metres round. Add the bodice and sleeves, some of which come out of the corners left over, and the total is close to 5 metres. Once the radius is longer than the fabric is wide, the halves no longer fit and the circle has to be built from narrower wedges, which is why long frocks jump in quantity.

Typical amounts by length

On 44 to 45 inch fabric, with a fitted bodice and full sleeves:

• Short umbrella kurti, flare ending at the hip or thigh: 2.5 to 3 m (2.75 to 3.25 yards).
• Knee-length frock: half circle 3 to 3.5 m (3.25 to 4 yards); full circle 4 to 4.5 m (4.5 to 5 yards).
• Calf-length frock: half circle 3.5 to 4.5 m (4 to 5 yards); full circle 5 to 6 m (5.5 to 6.5 yards).
• Floor-length frock: half circle 5 to 6 m (5.5 to 6.5 yards); full circle 7 to 9 m (7.75 to 10 yards).
• On 58 to 60 inch fabric: often half a metre to a metre less at knee and calf length, and about 6 to 6.5 m for a floor-length full circle, because the radius fits the width again.

Things a circle does not do well

• Borders. A straight printed or embroidered border cannot follow a curved hem, so a border along the bottom usually rules out a true umbrella cut.
• Stripes, checks and one-way prints. The pattern changes direction round the skirt. Some people like the effect; decide before you buy.
• Stiff cloth. Soft fabrics such as chiffon, georgette, crepe and lawn fall into waves. Crisp ones stand out like a lampshade.
• Level hems straight away. Parts of a circle hang on the bias and drop. It is normal practice to let a circular skirt hang before the hem is levelled.
• Sheer layers. A lining is needed, though it can be a slimmer A-line and use far less than the outer skirt. See georgette and chiffon.

Before you buy the fabric

Send the design, your height and the length you want on the Fabric + Stitching quote form if you would like us to supply the cloth; Fabric + Stitching explains how the fabric is agreed. If you are sending your own, add its width, and read our guide to checking you have enough fabric for what to measure first. Ask for the cut in your quote, and we confirm what is possible on your fabric and design.