An exposed zip is sewn with its teeth and tape showing on the outside of the garment, as a design detail rather than something to hide. The cleanest way to do it is the window method: interface the fabric, stitch a rectangle the length of the zip and about 1.2 cm (1/2 in) wide, slash and turn that window to the inside, then lay the zip behind it and topstitch around the opening. When the zip sits in a seam, you can skip the window, press the seam allowances back to the width you want to show and topstitch the zip from the right side.

Where do you use an exposed zip?

An exposed zip is a feature, so choose it where you want the hardware to be seen: the back neck of a shift dress, the front of a sweatshirt, a welt-style pocket on trousers, the side of a pencil skirt. It also solves a practical problem. Coated fabrics, faux leather, neoprene and thick wool are too stiff for an invisible zip, and an exposed zip avoids forcing them into a tight fold.

Pick a zip with teeth worth showing: brass or nickel metal teeth, or chunky molded plastic. A standard dress zip with fine coil teeth looks unfinished when exposed. Metal zips are shortened from the top, not the bottom, so buy the length you need or a little longer and read how to shorten a zip before you cut.

What do you need?

  • A metal or molded plastic zip: closed-end for a neckline or pocket, separating (open-end) for a jacket or sweatshirt front.
  • A strip of fusible interfacing 5 cm (2 in) wide and 5 cm longer than the zip. Use a knit interfacing on stretch fabric.
  • For the window method, a facing piece 8 cm (3 1/8 in) wide and 6 cm (2 3/8 in) longer than the zip, in self fabric or lining.
  • A zipper foot, a ruler, chalk or an erasable marker, sharp small scissors.
  • Wash-away basting tape or a glue stick to hold the zip while you topstitch.

How do you sew an exposed zip with the window method?

The window method puts the zip into a solid panel, with or without a seam behind it. Measure the zip first: the teeth length from top stop to bottom stop, and the width of the teeth. A size 5 metal zip has teeth about 6 mm (1/4 in) wide, and a window 1.2 cm (1/2 in) wide shows the teeth plus 3 mm of tape on each side, which keeps the pull from catching on the fabric.

  1. Interface the wrong side. Fuse the interfacing strip centered on the zip line, from the raw neck edge to 2.5 cm (1 in) below where the bottom stop will sit. If there is a seam at the zip position, sew it below the zip first and press it open.
  2. Mark the window on the facing. Draw a rectangle 1.2 cm wide and 3 mm (1/8 in) longer than the zip teeth on the wrong side of the facing piece, centered along its length. Its top edge sits on the neckline stitching line, 1.5 cm (5/8 in) below the raw edge, so the neck facing covers the top of the zip later.
  3. Stitch the window. Place the facing right sides together on the garment, lining up the rectangle with the zip line, and stitch around the rectangle with a short 1.5 mm stitch. Pivot at the corners and count stitches across the short ends so both are the same.
  4. Slash and clip. Cut down the middle of the rectangle to 1 cm (3/8 in) from each end, then cut diagonally into each corner, right up to the stitching without cutting through it. Short corner cuts are what cause puckered corners.
  5. Turn and press. Push the facing through the slash to the wrong side. Roll the seam so none of the facing shows from the right side, and press with a cloth. The window should be a crisp rectangle with square corners.
  6. Position the zip. Lay the zip behind the window, teeth centered, top stop 3 mm below the top of the window. Hold the tape with basting tape or a dab of glue stick on the tape only, never on the teeth. Close and open the zip once to check the pull runs clear of the fabric.
  7. Topstitch. From the right side, with the zipper foot, stitch 2 mm (1/16 in) from the window edge down one side, across the bottom and up the other side, through fabric, facing and tape. Sew both long sides from top to bottom rather than around in one pass if your fabric shifts, so the two sides are pushed the same way.
  8. Finish the inside. Trim the facing to 2 cm (3/4 in) around the window and catch its edges to the interfacing with a few hand stitches or a row of zigzag. Fold the top of the zip tape down and secure it under the neck facing when you finish the neckline.
Tip: On a dress or top, finish the neckline after the zip. The neck facing or binding then covers the folded tape ends, and the top stops sit right at the finished edge.

How do you sew an exposed zip in a seam?

In a seam, the seam allowances do the work of the window and there is nothing to slash. This is the usual method for a separating zip on a sweatshirt front or a zip down the center back of a skirt.

  1. Interface the seam allowances for the length of the zip, 2.5 cm (1 in) wide on each side, and finish their raw edges.
  2. For a closed-end zip, sew the seam below the zip and press it open. For a separating zip, the whole seam is the opening.
  3. Press each seam allowance to the wrong side so the two folded edges are 1.2 cm (1/2 in) apart, with 6 mm on either side of the seam line. On a 1.5 cm allowance that is a fold of 9 mm.
  4. Place the zip behind the opening, teeth centered in the gap, and hold it with basting tape. Match any horizontal seams or stripes across the zip before you stitch.
  5. Topstitch 3 mm (1/8 in) from each fold, from the top down on both sides, and across the bottom of a closed-end zip. A 3 mm stitch length looks neater than a short one on topstitching.

On sweatshirt fleece or any knit, the interfacing is not optional: the folded edges stretch during topstitching otherwise, and the zip ripples when closed. The sweatshirt pattern in Sewly lists the zip length among the notions when a front opening is chosen, which saves measuring the center front and guessing.

What are the most common mistakes with an exposed zip?

  • No interfacing. The window stretches as you turn it and the corners fray through the stitching within a few wears.
  • Window too narrow. The folds rub against the teeth, the pull jams and the fabric catches. Keep 3 mm of tape visible on each side of the teeth.
  • Uneven topstitching. Use the edge of the zipper foot as a guide and keep the same distance on both sides. Lengthen the stitch to 3 mm and use a topstitching needle on thick fabric.
  • Sewing over metal teeth. Keep the needle on the tape. Stop with the needle down, lift the foot and move the pull out of the way when you reach it.
  • Wrong zip length. Measure the opening on the pattern before buying, and shorten from the top if the zip is too long.

When should you use an exposed zip instead of an invisible or lapped zip?

Use an invisible zip when the closure should disappear into a seam, as on a fitted dress or a skirt in a fine fabric: the invisible zip guide covers the foot and the order of operations. Use a lapped zip when you want a traditional flap over the teeth and are working in a heavy fabric; how to sew a lapped zip explains the overlap. Choose the exposed zip when the hardware is part of the design, when the fabric is too thick or too stiff to fold tightly around a coil, or when you need a separating zip, which is never hidden. The pros and cons of each type are compared in invisible zip vs regular zip.