OK I did a test run with a zipper. I tried 2 ways. 1 with the teeth facing out and with the back facing out. I’ve read some where that when the backing faces out it gives more water resistance.
And something I tried is the following (I hope I can explain it clearly…)
Normally you sew the side of the zipper tape to the edge of the fabric. But I drew a 1cm mark from the edge of the fabric and minded the edge of the zipper with that line. The sew a line next to the zipper teeth. Then flip it over. Now you have a 1cm strip of extra fabric. Fold that over and tuck it under the zipper tape. Now you have a hemmed edge under the zipper.
See the drawing below. Red is fabric green the zipper and black the first stitch line.

The result:

The last stitch could be more to the edge…
What do you think of this option?




