Doina Alexei
  • Sewing Tutorials
    • Basics >
      • Aligning Pattern Grainlines To Fabric
      • Preparing Fabrics For Sewing
      • Pinning Sewing Patterns To Fabric
      • Placing Sewing Patterns On Fabric For Cutting
      • Rotary Cutters or Fabric Scissors?
      • Cutting The Sewing Patterns
      • What Are Notches And How To Use Them In The Sewing Process
      • Transferring Notches From Pattern To Fabric
      • Transferring Seamlines to Fabric
      • Staystitching
      • Backstitching: A Complete Guide
      • Hand Basting: A Complete Guide
      • Sewing Continuous Bias Binding
    • Darts >
      • Marking And Transferring Darts To Fabric
      • What Are Darts And Dart Components
      • Folding, Pinning And Hand Basting Darts
      • Handling Dart Excess: Bulk And Tension
      • How To Sew A French Dart
      • How To Sew And Iron Single Pointed Darts
      • How To Sew And Iron Contour Darts
      • Sewing Darts With Decorative/Beaded Fabrics
    • Sewing Seams >
      • ​The Basics Of Seams And Seam Allowance
      • How To Sew A Straight Seam
      • Sewing Curved Seams
      • Sewing Corner Seams
      • Trimming And Grading Seam Excess
      • Notching/Clipping Seam Allowance for Tension Release
      • Sewing Topstitched Seams
      • Sewing Corded Seams
      • Sewing A Slot Seam
      • Sewing A Gathered Seam
      • Sewing Bias Seams
      • Sewing Seams With Ease
      • Sewing Seams With Crossing Seamlines
      • Sewing Unlike Fabric Seams
      • How To Iron Seams: Ironing Tools And Conventions
      • Sewing With Knit Fabrics
      • Understanding Stitch Length And Tension
      • Sewing Unique Fabric Seams
    • Seam Finishes >
      • Seam Finishing Techniques - Overview
      • Applying A Pinked Seam Finish
      • Applying A Bias Bound Seam Finish
      • Serging And Zigzag Seam Finishes
      • Sewing A Self-Bound Seam Finish
      • Sewing A French Seam Finish
      • Sewing A Hong Kong Seam Finish
      • Sewing A Mock French Seam Finish
      • Sewing A Turned-and-Stitched Seam Finish
      • Sewing Overcast Hand-Applied Seam Finishes
      • Sewing A Flat Felled Seam
      • Sewing A Hairline Seam Finish
    • Hem Finishes >
      • Garment Hem Finishes: Overview
      • ​Sewing A Double Fold Hem Finish
      • Sewing A Single Fold Hem Finish
      • Sewing Bound Hem Finishes
      • Sewing An Exposed Double Layer Bound Hem
      • Sewing A Folded-Up Bound Hem with Pre-folded Binding
      • Sewing A Hong Kong Hem Finish
      • Sewing A Band Hem Finish
      • Sewing A Bias Faced Hem Finish
      • Sewing A Twill Tape Hem Finish
      • Sewing A Rolled Hem Finish
      • Sewing A Shaped Hem Facing
      • Using Fusible Hem Tape And Webbing
      • Finishing A Lace Fabric Hem
      • Finishing A Leather Hem
      • Sewing Faced Hem Corners
      • How To Finish Lining At The Hem
      • Finishing Fabric Corners by Mitering >
        • Mitering Fabric Corners With A Full Bias Facing
        • Mitering Fabric Corners With Exposed Binding
      • Interfacing A Hemline: Lined And Unlined Examples
    • Sewing Pockets >
      • Curved Patch Pocket With Flap
      • Unlined Square Patch Pockets
      • Lined Patch Pockets: Two Ways
      • Extension On-Seam Pockets
      • Separate On-Seam Pocket
      • Front Hip Pockets
      • Bound Double Welt Pocket
      • Double Welt Pocket With Flap
      • Self-Welt Pocket (Using Single Fabric Layer)
      • Slanted Welt Pocket (Hand-Stitched)
      • Faced Slash Pockets: Overview >
        • Sewing A Faced Slit Pocket
        • Sewing A Rectangular Slash Pocket
        • Sew A Star-Shaped Faced Pocket
    • Sewing Zippers >
      • Sewing Zippers: General Information
      • Sewing A Centered Zipper
      • Sewing A Lapped Zipper
      • Sewing An Invisible Zipper
      • Sewing A Fly Front Zipper
      • Sewing A Closed-End Exposed Zipper (No Seam)
      • Sewing An Exposed Separating Zipper
      • Sewing Hand Stitched Zipper Applications
      • Sewing A Zipper Underlay
      • Sewing A Placket-Enclosed Separating Zipper
    • Sleeveless Finishes >
      • Sleeveless Armhole Finishes: General Information
      • Finishing Sleeveless Garments with Lining
      • Sewing A Folded-Under Bound Armhole Finish
      • Sewing A Shaped Armhole Facing
      • Finishing Armhole Edges With Exposed Binding
      • Finishing Armhole Edges With Decorative Trim
    • Neckline Finishes >
      • Sewing A Neck Shaped Facing
      • Sewing An All-In-One Neck Facing
      • Neck And Garment Opening Combination Facings >
        • Sewing An Extended Front-Neck Facing
        • Sewing A Separate Neck-Front Facing
      • Sewing A Bias Faced Neckline Finish
      • Sewing A Band Neckline Finish
      • Bound Neckline Finishes: Overview >
        • Sewing A Single Layer Bound Neckline
        • Finishing A Neckline With Pre-Folded Binding
        • Sewing A Double Layer Bound Neckline Finish
      • Sewing A Semi-Stretch Strip Band Neckline
      • Ribbed Neck Band And Classic Turtleneck
      • Decorative Neckline Finishes >
        • Sewing A Neckline With Decorative Inset
        • Sewing A Piped Cording Faced Neckline
        • Sewing Decorative Trim To A Finished Neckline
    • Finishing Facing Edges >
      • Finishing Facing Edges: Overview
      • Folded-And-Topstitched Overedge Facing Finish
      • Sewing A Bound Facing Edge Finish
      • Sewing A Hong Kong Facing Finish
      • Sewing A Rolled Edge Facing Finish
      • Sewing A Twill Tape Facing Edge Finish
      • Sewing An Overedge-Stitch Facing Finish
    • Extras >
      • A Complete Guide on Interfacing
      • Sewing Bound Spaghetti Straps
      • Sewing Spaghetti Straps To A Faced Neckline
      • Sewing Ruffles: Overview
      • Patterning And Sewing A Circle Ruffle
      • Sewing A Gathered Heading Ruffle
      • Sewing Double Layer Gathered Ruffles
      • Sewing A Gathered Ruffle Into A Seam
      • Sewing A Gathered Ruffle To A Fabric Edge
      • Sewing A Fabric Surface Slit
      • Sewing A Slit Seam
      • Hand-Applied Straight Stitches
      • Hand-Applied Blind Stitches
      • Hand-Applied Overedge Stitches
      • Hand-Applied Tack Stitches
      • Hand-Applied Decorative Stitches
  • Custom Apparel
    • Custom Bridal
  • Submit A Sewing Question
  • About
  • Blog

Two Types Of Zipper Underlays And To Sew Them

What Is A Zipper Underlay
A zipper underlay is a single or double layered fabric panel that provides a protective barrier between the skin and the zipper during wear. An underlay is conventionally built as a separate unit featuring enclosed seam allowance edges. 
Picture
The only zipper application that absolutely requires an underlay is a fly front zipper. This trouser zipper uses something called a fly shield as a protective underlay. Zipper underlays are more commonly used with bottoms like skirts and trousers. In this case, they are stitched to the back of a zipper prior to attaching the waistband. 
Picture
​A zipper underlay is a separate add-on that not only increases comfort but also provides a cleaner look on the inside of the garment. Even if your sewing patterns do not specify the use of an underlay, you can make the decision to add one if you experience skin sensitivity to the zipper teeth or tape.
​Keep in mind that an underlay does not work with all zipper applications. Due to its linear, rectangular shape, an underlay may not be suitable for use with side seam invisible zippers, or other similar styles that are built to mold around the organic shape of the body, especially if form fitted. A regular double-layer underlay will add unnecessary bulk to the seam. 
​If a regular underlay is not suitable, you should consider cutting the underlay at a narrower width and using lightweight fabric. 
Picture
Picture
A single layer style, called a ribbon underlay can also be used. While the ribbon application is not covered in this tutorial, it can be constructed the same way as the conventional underlay shown below.
Picture
​There are two ways to construct a conventional underlay: Sewing two identical fabric pieces together or folding a single fabric layer in half to self-finish. Both versions enclose the seam allowances for a clean-finished look. 
The single fabric layer option is the easiest to complete but limits you to using only a rectangular shaped underlay. If you prefer an underlay that has a curved bottom edge (like a classic fly shield, for example) then two separate fabric layers must be used. Both examples are shown below.

How To Sew A Curved Edge Zipper Underlay

Assuming there are no underlay patterns provided with your pattern set, you can draw and cut the fabric underlay piece(s) directly from the fabric.
Picture
1. Fold the fabric at about 3" from the edge with face sides touching- fabric wrong side should correspond to the outside of the fold. ​​Pin the two fabric layers along the edges to keep them from shifting in the steps to follow.
Picture
Measure the length of your zipper tape to determine the length of your underlay. Keep in mind, you need the length of the zipper tape and not the zipper teeth.
Picture
2. Using a ruler and tailor’s chalk or a quilting pencil, draw a rectangle on the lengthwise grain (parallel to the fabric selvage) measuring 2” wide and the length of the entire zipper tape- 8” in this case. 
Picture
3. ​Draw a curved line at one of the corners. You can do this by manually smoothing out the rectangular corner or use a French curve for a perfectly curved edge.
Picture
4. Insert a few pins along the rectangle, through both fabric layers as shown. Cut both fabric layers simultaneously along the marked lines, being careful not to shift the two fabric layers away from each other as you cut.
Picture
5. Keeping the two fabric layers as they are, pin horizontally through both layers along the outer curved edge as shown. Leave the top and straight edge open.
Picture
​6. Stitch the curved edge at ¼” seam allowance.
Picture
7. Notch the curved area of the seam allowance with wedge-shaped clips as shown. This will minimize bulk and allow the curve to stay smooth and lay flat.  
Picture
8. Flip the underlay on its right side, bring the curved edge out and iron it flat.
Picture
Picture
9. Clean finish the straight edge of the underlay. You can use an overedge stitch like serging or zigzag. ​In this tutorial, one of the layers was trimmed by ¼” and the other was folded over it and topstitched to enclose it.
Picture
10. Place the underlay to the wrong side of the closed zipper application such that the underlay’s top edge aligns with the garment’s top edge, and its lengthwise straight edge aligns with the zipper’s seam allowance edge as shown. Pin through the underlay’s straight edge and garment seam allowance layer as shown.
Picture
11. Stitch the underlay and garment edges together as shown.
Picture
12. ​Tack the bottom of the underlay to the seam allowance layer underneath.

How To Sew A Self-finished (Folded) Zipper Underlay

Picture
1. To cut a self-finished underlay, lay out the single fabric layer with the wrong side facing up and draw a rectangle that is 5” wide and the length of the zipper tape: in this case, 8”. Use a ruler and tailor’s chalk (or fabric pencil) to draw the rectangle directly on fabric.
Picture
2. ​Carefully cut the rectangle out.
Picture
3. Fold the rectangular fabric strip lengthwise down the center such that the face sides are touching. Insert pins horizontally to keep the bottom edges together as shown.
Picture
​4. Stitch the pinned bottom edges closed at ¼” seam allowance.
Picture
5. Flip the underlay on its right side and iron the finished bottom edge as shown.
Picture
6. Making sure the open lengthwise edges are matching, iron down the center fold to crease.
Picture
7. Clean finish the open lengthwise edges either using the method shown in the example above or an overedge stitch. In this case, a serging stitch is used to close and simultaneously finish the underlay. You do not need to clean finish the top horizontal edges as these will be sewn into another seam or a waistband.
Picture
​8. Align the serged edge of the underlay to the garment seam allowance. 
Picture
Picture
9. Last but not least, stitch and hand-tack the underlay’s bottom edge as described above. 
DMCA.com Protection Status
All content, including images and text, may not be copied, replicated, or redistributed without express written permission. This website is regularly screened and monitored for content protection.

Have A Personalized Sewing Question?

Ask It Here

Services

​Custom Apparel
Custom Bridal
​Sewing Tutorials
​

Company

About
Blog

Support

Contact
Terms of Service
DMCA.com Protection Status
© COPYRIGHT 2022. ALL RIGHTS RESERVED.
  • Sewing Tutorials
    • Basics >
      • Aligning Pattern Grainlines To Fabric
      • Preparing Fabrics For Sewing
      • Pinning Sewing Patterns To Fabric
      • Placing Sewing Patterns On Fabric For Cutting
      • Rotary Cutters or Fabric Scissors?
      • Cutting The Sewing Patterns
      • What Are Notches And How To Use Them In The Sewing Process
      • Transferring Notches From Pattern To Fabric
      • Transferring Seamlines to Fabric
      • Staystitching
      • Backstitching: A Complete Guide
      • Hand Basting: A Complete Guide
      • Sewing Continuous Bias Binding
    • Darts >
      • Marking And Transferring Darts To Fabric
      • What Are Darts And Dart Components
      • Folding, Pinning And Hand Basting Darts
      • Handling Dart Excess: Bulk And Tension
      • How To Sew A French Dart
      • How To Sew And Iron Single Pointed Darts
      • How To Sew And Iron Contour Darts
      • Sewing Darts With Decorative/Beaded Fabrics
    • Sewing Seams >
      • ​The Basics Of Seams And Seam Allowance
      • How To Sew A Straight Seam
      • Sewing Curved Seams
      • Sewing Corner Seams
      • Trimming And Grading Seam Excess
      • Notching/Clipping Seam Allowance for Tension Release
      • Sewing Topstitched Seams
      • Sewing Corded Seams
      • Sewing A Slot Seam
      • Sewing A Gathered Seam
      • Sewing Bias Seams
      • Sewing Seams With Ease
      • Sewing Seams With Crossing Seamlines
      • Sewing Unlike Fabric Seams
      • How To Iron Seams: Ironing Tools And Conventions
      • Sewing With Knit Fabrics
      • Understanding Stitch Length And Tension
      • Sewing Unique Fabric Seams
    • Seam Finishes >
      • Seam Finishing Techniques - Overview
      • Applying A Pinked Seam Finish
      • Applying A Bias Bound Seam Finish
      • Serging And Zigzag Seam Finishes
      • Sewing A Self-Bound Seam Finish
      • Sewing A French Seam Finish
      • Sewing A Hong Kong Seam Finish
      • Sewing A Mock French Seam Finish
      • Sewing A Turned-and-Stitched Seam Finish
      • Sewing Overcast Hand-Applied Seam Finishes
      • Sewing A Flat Felled Seam
      • Sewing A Hairline Seam Finish
    • Hem Finishes >
      • Garment Hem Finishes: Overview
      • ​Sewing A Double Fold Hem Finish
      • Sewing A Single Fold Hem Finish
      • Sewing Bound Hem Finishes
      • Sewing An Exposed Double Layer Bound Hem
      • Sewing A Folded-Up Bound Hem with Pre-folded Binding
      • Sewing A Hong Kong Hem Finish
      • Sewing A Band Hem Finish
      • Sewing A Bias Faced Hem Finish
      • Sewing A Twill Tape Hem Finish
      • Sewing A Rolled Hem Finish
      • Sewing A Shaped Hem Facing
      • Using Fusible Hem Tape And Webbing
      • Finishing A Lace Fabric Hem
      • Finishing A Leather Hem
      • Sewing Faced Hem Corners
      • How To Finish Lining At The Hem
      • Finishing Fabric Corners by Mitering >
        • Mitering Fabric Corners With A Full Bias Facing
        • Mitering Fabric Corners With Exposed Binding
      • Interfacing A Hemline: Lined And Unlined Examples
    • Sewing Pockets >
      • Curved Patch Pocket With Flap
      • Unlined Square Patch Pockets
      • Lined Patch Pockets: Two Ways
      • Extension On-Seam Pockets
      • Separate On-Seam Pocket
      • Front Hip Pockets
      • Bound Double Welt Pocket
      • Double Welt Pocket With Flap
      • Self-Welt Pocket (Using Single Fabric Layer)
      • Slanted Welt Pocket (Hand-Stitched)
      • Faced Slash Pockets: Overview >
        • Sewing A Faced Slit Pocket
        • Sewing A Rectangular Slash Pocket
        • Sew A Star-Shaped Faced Pocket
    • Sewing Zippers >
      • Sewing Zippers: General Information
      • Sewing A Centered Zipper
      • Sewing A Lapped Zipper
      • Sewing An Invisible Zipper
      • Sewing A Fly Front Zipper
      • Sewing A Closed-End Exposed Zipper (No Seam)
      • Sewing An Exposed Separating Zipper
      • Sewing Hand Stitched Zipper Applications
      • Sewing A Zipper Underlay
      • Sewing A Placket-Enclosed Separating Zipper
    • Sleeveless Finishes >
      • Sleeveless Armhole Finishes: General Information
      • Finishing Sleeveless Garments with Lining
      • Sewing A Folded-Under Bound Armhole Finish
      • Sewing A Shaped Armhole Facing
      • Finishing Armhole Edges With Exposed Binding
      • Finishing Armhole Edges With Decorative Trim
    • Neckline Finishes >
      • Sewing A Neck Shaped Facing
      • Sewing An All-In-One Neck Facing
      • Neck And Garment Opening Combination Facings >
        • Sewing An Extended Front-Neck Facing
        • Sewing A Separate Neck-Front Facing
      • Sewing A Bias Faced Neckline Finish
      • Sewing A Band Neckline Finish
      • Bound Neckline Finishes: Overview >
        • Sewing A Single Layer Bound Neckline
        • Finishing A Neckline With Pre-Folded Binding
        • Sewing A Double Layer Bound Neckline Finish
      • Sewing A Semi-Stretch Strip Band Neckline
      • Ribbed Neck Band And Classic Turtleneck
      • Decorative Neckline Finishes >
        • Sewing A Neckline With Decorative Inset
        • Sewing A Piped Cording Faced Neckline
        • Sewing Decorative Trim To A Finished Neckline
    • Finishing Facing Edges >
      • Finishing Facing Edges: Overview
      • Folded-And-Topstitched Overedge Facing Finish
      • Sewing A Bound Facing Edge Finish
      • Sewing A Hong Kong Facing Finish
      • Sewing A Rolled Edge Facing Finish
      • Sewing A Twill Tape Facing Edge Finish
      • Sewing An Overedge-Stitch Facing Finish
    • Extras >
      • A Complete Guide on Interfacing
      • Sewing Bound Spaghetti Straps
      • Sewing Spaghetti Straps To A Faced Neckline
      • Sewing Ruffles: Overview
      • Patterning And Sewing A Circle Ruffle
      • Sewing A Gathered Heading Ruffle
      • Sewing Double Layer Gathered Ruffles
      • Sewing A Gathered Ruffle Into A Seam
      • Sewing A Gathered Ruffle To A Fabric Edge
      • Sewing A Fabric Surface Slit
      • Sewing A Slit Seam
      • Hand-Applied Straight Stitches
      • Hand-Applied Blind Stitches
      • Hand-Applied Overedge Stitches
      • Hand-Applied Tack Stitches
      • Hand-Applied Decorative Stitches
  • Custom Apparel
    • Custom Bridal
  • Submit A Sewing Question
  • About
  • Blog