Pattern Making: Elastic Waist Pants

You don’t need to buy a pattern when it comes to elastic pants… just your favorite pair and few basic tips!  For this tutorial, I made a pair of baby pants because they are small and easier to photograph.

Finished pants size 6-12 mos

Fabric, Supplies and Notions:

Favorite pair of elastic pants (baby/kid, yoga, PJ/lounge pants work best)

Woven or knit fabric (see sewing instructions for yardage)

1 package of elastic (somewhere between 3/4 inch and 1 1/4 inch width)

Basic sewing supplies plus chalk

Sewing Instructions:

Seam allowance: 1/2 inch unless otherwise noted

Time: 2 hours (45 minutes with a serger), includes cutting fabric

Amount of fabric: Measure the length of your pants from top of waistband to bottom of hem and add 9 inches.  This should be enough fabric to copy the pattern as well as increase the size by 1 to 2 sizes.  (So, if the pants are 12 inches long: 12 + 9 = 21) If making pants for baby and toddler, use this yardage. (21 inches, or roughly 5/8 yard)  If making for older kids/adults, you will need up to double this yardage, depending on how wide your panels are and whether or not you use 45″ or 60″ fabric.  So, you can either buy double and use the excess for something else or take the pants to the fabric store and lay them out on your fabric at the cutting table.

Step 1:  Trace Your Pattern

Note:  Your pants are made out of 4 panels: left and right front and left and right back.  The back pieces are wider than the front to allow room for the seat.

Begin by folding your fabric in half, matching the selvages.

Fold your pants in half.  This is the width of your back pieces.  Place your pants on your fabric, matching the grainlines (the actual lines of thread that run parallel to the selvages).

Make sure pants follow the grainline (to the right of the fabric are the selvages)

Using the chalk, trace the pants.  If your pants have an elastic waist, stretch it out to make sure you are cutting enough fabric.

Stretch elastic to see/trace shape without gathering

If you are making the same size, add an extra 1/2 inch to the sides, an extra 1 1/2 inch at the hems and an extra 2 to 2 1/2 at the waist.  Otherwise, add these measurements onto any additional length/width you add.

Use chalk to trace pants. (The original pair is a 3-6 mos. I wanted the new pair to be 6-12 mos. and a little wider leg, so I traced accordingly.)

Then, flip the pants and trace again.  This time, add the same amount to the top and bottom, but trace no greater than 1/2 inch away from the finished pants (this is because this side is the front).

Flip and trace again (front panels)

Cut out the pieces and mark with an F or B for front and back.

Before cutting

After cutting. Back (left) and front (right) pieces. Note how the back is wider and the curved crotch seam is a little bit deeper

Step 2:  Sew Inner Leg Seams

Match one front and one back piece, right sides together.  Pin from curve of the crotch to bottom of hem.  Straightstitch, clip and overcast (or serge) inner leg seam.

Match one back and one front, right sides together, at inner leg seams and pin from curve to bottom hem.

The pieces will NOT match up–remember the back is bigger to allow room for the seat of the pants!

Can you see how the pieces don’t match up perfectly?

Example of a finished inner leg seam

Step 3: Sew Crotch

Match the 2 pieces together, right sides together and pin curve of the crotch,  Straightstitch, clip and overcast (or serge).  Along the bottommost curve, sew another line to reinforce the crotch.

Here are the two sides with finished inner leg seams

Here is the finished crotch of the pants

Step 4: Sew Outer Leg Seams

This is tricky!!!  Flip the pants so that the right sides are together.  DO NOT SEW ALONG OUTER SEAMS AS IT IS PLACED AFTER YOU SEW THE CROTCH!  (Unless you are bowlegged and have extremely short legs and an incredibly wide torso!

Flip the pants so that the right sides are together and it looks like an inside-out pair of trousers.

If your pants look like this before you sew the outer leg seams–STOP!

This is how your pants should look before you sew the side seams (right sides together!)

Straightstitch, clip and overcast outer leg seams.

Step 5: Hem

Even out the raw edges of the waistband and leg openings (if any).

If the waistband or hem of the pants has any great discrepancy, use scissors or a straight edge and rotary cutter to even up the edges.

Keeping pants inside out, press (iron) hem up 1 1/2 inches.

After you iron raw edge up 1 1/2 inches, open the fold and you’ll have a nice crease

Then, open the hem (you should have a nice crisp crease now and turn the raw edge toward the crease.  Press closed.

Fold up the raw edge to the crease and press again

Finally, fold up original crease, capturing the raw edge neatly inside and adding some weight to your hem. Iron everything a final time.

Pin hem. Starting at the inner leg seams, sew hem closed as close to the turned under edge as possible.  Reverse when you reach the beginning again.

Sew close to the top in order to create a deeper hem and in order to catch the three layers

Step 6:  Make Casing and Insert Elastic

Repeat Step 5 for the waistband, only pressing under 2 inches and turning and pressing the raw edge (for 3/4 inch elastic) or pressing under 2 1/2 inches and turning and pressing the raw edge  (for 1 inch elastic).

Start sewing the casing closed at the back and leave a 1 to 2 inch inch opening at the back (roughly where a tag would be).

Measure elastic (using the original pair of pants as your guide) and add 2 inches.  Fasten a safety pin to one end of the elastic and secure the other end with a straight pin (to avoid losing it in the casing).

Push the elastic through using a safety pin

Prevent elastic from getting “lost” by securing the other end with a straight pin

Feel to make sure elastic is not twisted, overlap ends by 1 inch and pin together.  Sew together with a zig-zag stitch, reversing several times.

Before sewing elastic, you may want to pin ends together and try on the pants to make sure fit is good

Stretch and “snap” elastic in place.  Switch sewing machine back to straightstitch. Pull fabric taught and sew casing closed.  Be sure to reverse a bit at beginning and again at the end.

Put on the pants and smile!

Finished pants (with an airplane applique)