Sewing 117 - How to Sew A Zipper Fly

Hello everyone. I am currently working on a pair of trousers and thought it would be nice to share how I sew in a zipper fly. I feel this method is easy to understand even for beginners, so let's get to it. 

Things you need for the Zipper Fly

1. A zipper (8inch or 20cm long)

2. Fly Facing - 2inches (5cm) by 6inches (15cm) rectangle

3. Underlap - 2.5inches (6.5cm) by 6inches (15cm) rectangle

   
   

   

   
   

You can vary the sizes based on your projects. The zipper should be a little longer than you need and so should the fly facing/Underlap. The underlap can be doubled to make it stronger.

4. Interfacing for the Facing and underlap

5. The Front pieces of your Project. It could be trousers or a skirt. Please make sure you have already added seam allowances to your pattern. I'm using 1/2inch (1.2cm) allowances.

Steps to sew a Zipper Fly

1. Join the Two Front pieces of the trouser at the centre front seam up to the point where the zipper will stop.

   
   

   

   
   

2. Interface your fly pieces and finish the raw edges before use. On the Left hand side of the Trouser, place the Fly Facing, right sides together at the centre front opening and stitch together, sewing at 1/2inch (1.2cm)seam allowance.

   
   

   

   
   

3. Press the seam flat and understitch or edgestitch very close to the seam to keep the fly facing in place.

   
   

   

   
   

4. Open up the fly facing flat. Place the zipper, face down along the seam line (centre front), keeping the zipper teeth on the fly facing piece. Be sure to keep the zipper head below the waist line.

5. Baste the zipper in place and stitch the zipper to the fly facing only.

6. 

   Fold the zipper and fly facing to the inside of the trousers.

7. On the right hand side of the Trousers, fold and press 1/4inch (6mm) along the centre front edge to the inside of the trousers. This is half of your seam allowance width. This is key, as we want the lefthand side to overlap the righthand side of the zipper opening.

   

8. With the Zipper closed up, align the now folded edge of the Trouser front along the teeth of the zipper. Keep it close, but do not overlap the teeth. Baste in place and Stitch the zipper to the trousers along the edge. Test zipper to check for errors. Everything should be nice and flat. Clip the seam a little below the zipper opening to help the seam allowance lay flat.

   
   

   

   
   

9. Turning the Trousers to the inside, place the Underlap, right side down, over the zipper to cover it. Baste in place.

   
   

   

   
   

10. Turn the Trousers back to the outside and stitch the underlap to the trousers and zipper, either over the previous stitching line or very close to it.

Note that you can do both steps 8 and 9 together if you baste everything in place first (See video below)

11. If you have done it right, the lefthand side of the trouser should overlap the righthand side, hiding the zipper completely.

12. Top stitch the Zipper Fly Pattern on the Lefthand side catching the Fly facing beneath. Be sure to move the underlap out of the way. Make a bartack over the end of the zipper to secure everything.

    
    

    

    
    

13. Finally, tack the fly facing and underlap at the bottom to keep them together and clip the seam below the zipper if needed.

Appendix

Thank you for reading and if you try it out, do let me know how it worked out for you.

Did you know that you can also watch this lesson? Visit our channel and don't forget to subscribe to receive updates about new videos!

https://www.youtube.com/watch?v=zgfVzun96bo

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