Lapped Zipper Tutorial + Changing Zipper Location
This lapped zipper and pocket technique comes from studying several vintage 1940s and 50s dresses in my collection. It makes for a clean and easy side, front, or back lapped zipper while making it possible to have two full pockets with a side zip closure!
A facing is used to create the lap without having to adjust seam allowances. This piece is included with most of my patterns, but if you’d like to try the technique with another pattern, the width is 1in/2.5cm + Seam Allowance and length is Zipper Length + 2in/5cm.
The t-marks denote the length and placement of the zipper opening (Zipper Length); an additional 1in/2.5cm is added above and below this length.
Standard Zipper Option: omit the lapped zipper facing and sew using your preferred standard zipper insertion method
Changing Zipper Location
Because this lapped zipper technique utilizes seam allowances, many JMD patterns can become compatible with a front, back, or side zipper with a few easy steps, even if it wasn’t originally called for in the pattern.
Consider if the pattern is compatible with your desired zipper placement.
-A front-buttoning garment can be replaced with a front zipper, but the overlap will need to be removed and a new seam allowance added back in.
-Changing zipper placement may not be possible for certain designs or may not produce as flattering of a result.
Adding a front or back zipper may require splitting a pattern piece cut on the fold into two separate pieces. Add the seam allowance to the fold of the selected piece prior to cutting. (JMD uses .5in/1.3cm seam allowances). Don’t forget to adjust all affected pieces, including facings, bodice front or back, and skirt pieces.
Mark the length and placement of the new zipper opening
Order of sewing will change slightly to accommodate the new zipper location, although the zipper insertion technique will remain the same. For example, if a side zipper is being changed to a back zipper, the side seams will be sewn together and the back seam will be left open from the neck to the bottom of the zipper opening.
If a back neck facing is split, only use it to finish the top neckline- leave the facing raw edges against the center back and sew to the zipper. Ignore earlier pattern instructions for a button or hook back closure if present
A hook and eye are recommended to finish the tops of front and back zippers.
Lapped Zipper- Front or Back Zipper, or Side Zipper Without Pockets
1. If seam finishes are being used, finish the edges of the lapped zipper facing.
2. Pin the lapped zipper facing to the front bodice and side skirt, matching at the T-marks. Pin the 1in/2.5cm of facing above and below the T-marks to the front-side seam allowance.
Sew together using a .5in/12mm seam allowance between the two T-marks. Sew within the .5in/12mm seam allowance for the extensions above and below the T-marks.
Press seam toward the lapped zipper facing. Understitch the lapped zipper facing
3. With right sides facing each other, pin the left edge of the closed zipper to the right-hand side of the opening (opposite to the lapped zip facing), matching notches. Stitch in place .25in/6mm from the zipper tape’s edge.
Keep zipper closed. Understitch this seam with the seam allowance pressed to the right (in the same direction as the zipper tape). Take care to ensure zipper position is straight on both sides of the tape.
Four basting options can be selected for the next step. Key points of alignment are the top and bottom of the opening and the waist seam.
Closure not aligning smoothly? Try moving the edge of the zipper placket further to the right of the zipper edge to reduce the amount of excess fabric. (The placket can also be moved to the left if necessary.
Option 1: Hand-baste the lapped zipper placket to the zipper.
NOTE: For Options 2 and 3, the basting medium must first be tested on a scrap piece of fabric to ensure that it will not cause damage or leave a residue.
Option 2: Use a water-soluble glue or tape that can be washed out to attach the lapped zipper placket to the zipper.
Option 3: Use a no/low-residue tape like painter’s tape, washi tape, or translucent tape to hold the lapped zipper placket in place.
Option 4 (Advanced difficulty): Pin the lapped zipper placket to the zipper
4. Draw a straight stitch guide using tailor’s chalk or a washable fabric marker. Carefully stitch down the lapped zipper placket.
I prefer to start roughly about 1in/2.5cm below the zipper pull and stitch towards the bottom, where I finish the stitching by sewing across the placket. Afterwards, I open the zipper and finish sewing the top in the same manner.
(Advanced difficulty) The stitch guide is recommended, but not required. HOWEVER! It’s very important to take care and work slowly to not sew through the zipper teeth and to minimize bent or broken sewing machine needles. I use a regular zipper foot and regularly pause to check the location of the zipper.
5. Remove basting stitches or material and open zipper.
Side Lapped Zipper With Pockets
(The full pocket technique can be found in most JMD patterns featuring a side closure and will be mentioned in the pattern description)
1. If seam finishes are being used, finish the edges of the lapped zipper facing.
Don’t forget to stitch the tops of the anchored pockets to the waist seam!
2. Pin the lapped zipper facing to the front bodice and side skirt, matching at the T-marks. Taking care not the pin the front pocket piece, pin the 1in/2.5cm of facing above and below the T-marks to the front-side seam allowance.
Taking care not to sew the front pocket piece, sew together using a .5in/12mm seam allowance between the two T-marks. Sew within the .5in/12mm seam allowance for the extensions above and below the T-marks.
Press seam toward the lapped zipper facing. Understitch the lapped zipper facing.
3. With right sides facing each other, pin the left edge of the closed zipper to the right-hand side of the opening (opposite to the lapped zip facing), matching notches. Stitch in place .25in/6mm from the zipper tape’s edge.
Keep zipper closed. Understitch this seam with the seam allowance pressed to the right (in the same direction as the zipper tape). Take care to ensure zipper position is straight on both sides of the tape.
Four basting options can be selected for the next step. Key points of alignment are the top and bottom of the opening and the waist seam.
Closure not aligning smoothly? Try moving the edge of the zipper placket further to the right of the zipper edge to reduce the amount of excess fabric. (The placket can also be moved to the left if necessary.
Option 1: Hand-baste the lapped zipper placket to the zipper.
NOTE: For Options 2 and 3, the basting medium must first be tested on a scrap piece of fabric to ensure that it will not cause damage or leave a residue.
Option 2: Use a water-soluble glue or tape that can be washed out to attach the lapped zipper placket to the zipper.
Option 3: Use a no/low-residue tape like painter’s tape, washi tape, or translucent tape to hold the lapped zipper placket in place.
Option 4 (Advanced difficulty): Pin the lapped zipper placket to the zipper.
4. Draw a straight stitch guide using tailor’s chalk or a washable fabric marker. Upon reaching the waist seam, continue the guide along the back pocket. Upon reaching the lower pocket corner, continue the guide onto the skirt.
(Advanced difficulty) The stitch guide is recommended, but not required. HOWEVER! It’s very important to take care and work slowly to not sew through the zipper teeth and to minimize bent or broken sewing machine needles. I use a regular zipper foot and regularly pause to check the location of the zipper.
5. I prefer to start stitching roughly about 1in/2.5cm below the zipper pull. Carefully stitch down the lapped zipper placket, stopping at the waist seam. Reinforce stitching at the waist seam.
6. Taking care not to stitch through the top layer of the pocket, resume stitching along the back pocket until the lower pocket corner is reached. Stop and reinforce stitching.
7. Reposition the material to avoid stitching through the front pocket. Continue sewing along the stitch guide.
I prefer to finish the stitching by sewing across the placket. Afterwards, I open the zipper and finish sewing the top in the same manner.
8. Remove basting stitches or material and open zipper.
