How to make a Skirt Sloper

Sloper is a mold of the body with wearing ease and they don’t have any design details and no seam allowances. Once you get a perfect fit in your sloper, you’ll get a perfect fit in any of your other patterns. The basic slopers are:

Skirt Sloper
Bodice Sloper
Pants Sloper
Sleeve Sloper

Pattern Making Supplies

To draft your skirt sloper (or any other sloper) you’ll need the following supplies:

Tape Measure
Pattern Paper
tag or Poster Board
18″ Transparent Ruler with Grid
Drafting Curve Ruler
Pencils and Eraser
Tracing Paper
Tracing Wheel
Transparent Tape
Awl
Paper Scissors
Fabric Shears
Fit fabric such as muslin
Pins and pattern weights
Pattern Notcher
Pattern Hooks
Pattern Punch

Taking the Measurements

Stand and look straight, with parallel feet about 4″ apart. (If you are making the sloper for yourself, you will need a helper)
wrap 1/4″ elastic around the waist (1/4″ above the belly button)
The measurements that you’ll need for the skirt sloper are:
- waist
- high hip (at the hip bone, around 4 1/2″ below the waist)
- low hip (widest part of the hip, around 8 1/2 below the waist)

Use 20″ for the sloper length – the length of the skirt is adjusted based on the skirt design.

Calculations

Waist

add 1/2″ of ease and divide by 4.
add 1/4″ to the front (more for a person with a big belly)
subtract 1/4″ to the back (or the same amount added to the front)

High Hip

add 1″ of ease and divide by 4.
add 1/4″ to the front
subtract 1/4″ to the back

Low Hip

add 1 1/2″ of ease and divide by 4.
add 1/4″ to the front
subtract 1/4″ to the back

Tip: The amount added to the front varies from person to person. If a person has a big belly, the amount to be added to the front should be bigger to accommodate for the belly. You should subtract to the back, the same amount you add to the front.

Skirt Blocks

Draw two rectangles side by side. One will be for the front of the skirt sloper and the other for the back of the skirt.

The first rectangle measurement:

widest measurement calculation – front
20″ long

2nd rectangle measurement

widest measurement calculation – back
20″ long

W = Waist, HH = High Hip, LH = Low Hip

One Dart Skirt Sloper – Front

Start drafting from the Center Out – Make sure you are using the front calculations.

Measure the low hip calculation and mark on the LH line (point A)
Measure the high hip calculation and mark on the HH line (point B)
Use the same high hip measurement for the base (point C)
Use the following table to determine the start of the dart distance: (point D)

Calculate the difference between the waist with ease and the low hip with ease.
Use the following table to determine dart width (point E) and length (Point F):

Add the dart width to the waist calculation with ease and mark (point G)
Draw the Waist Contouring – come down 1/2″ (point H), square the line for 3/4″-1″ and use a curve ruler to connect with the side.
Draw the dart lines – square down to the waist contouring and connect to the dart length (point F).
Draw the hip curve connecting Waist, Low Hip, and High hip (points G, A, and B)
Label the Center Front (CF) and the Side

This is how your front skirt sloper should look like:

One Dart Skirt Sloper – Back

Make sure you are using the back calculations.

Draw Back Contouring – From center back, came in 3/8″ (point A) and come down 1/2″ (point B) to account for waist contouring. Then, blend the line at 7″ (point C).
Find the center of the waist calculation and mark the dart (point D) (in the back the placement of the dart is centered)
Mark the dart width (points E and F) – The width of the dart should be the same width as in the front minus 3/8″ used for the back contouring.
Mark the waist point (point G) – adding the dart width and the back contouring.
Draw the waist contouring – square from point B about 3/4″-1″ and use a curve ruler to connect to the waist point G.
Draw the dart legs – determine the length of the dart using the same table as in the front (point H) – square down the dart legs from the waist contouring and connect to point H.
Mark the High Hip calculation (I).
Mark the Low Hip calculation (J).
Draw the side line using a curve ruler.
Label Center Back (CB) and the side.

This is how your back sloper should look like:

Checking the Fit

Add seam allowance (I like to use 1/2″) and sew your sloper in muslin (or any fabric with no stretch) to check the fit.
Make any adjustments if needed.

Finishing the Slopers

True up the darts – fold the dart and mark the stitching line using a tracing wheel.
Trace the tracing wheel marks

Tip: Fold the front sloper darts to the sides (to avoid bulk in the belly area) and fold the back sloper darts to the Center Back.

Transfer your sloper on tag or poster board (this will be your mold for any skirt)
Mark the following notches in the front sloper and in the back sloper:
- dart legs
- low hip (on the sides)
- mark two notches on center back.
Mark the dart vanishing point with an awl punch.
Mark the fold line on Center Front
Cut your skirt slopers (Front and back)
Mark the grainline parallel to the skirt block

This is how your slopers should look like:

I takes time to draft your skirt sloper, but the effort is worth it. You can use the sloper to make any skirt design and also to adjust the fit in commercial skirt patterns.

Need inspiration for your skirt? This post has great skirt design ideas!

Skirt Designs