I recently came across a construction method that i thought could be quite manageable. But be forewarn, it’s still not meant for the faint-hearted, and i do highly recommend making a simplified version i.e. no lining, if you are new to making skirts.
Firstly, you want to give the extra seam allowances to your face and lining fabrics as shown above.
We will deal with the right side of the skirt first. Sew a safety stitch around the corners as shown. The corner is where the vent starts.
Press a double turn hem for the lining (1cm width) and topstitch it halfway (i.e. not all the way to the side seam).
With the right sides facing and the edges of the extensions aligned, stitch the face fabric and lining together using a 1.5cm seam allowance.
Press the face fabric at the extension such that the lining lines up exactly as the face fabric at the side seam as shown above.
Turn up the hem for the face fabric and we can choose to stitch down or secure by hand.
Now, we will construct something similar for the left side of the skirt (see above image). Again, we would do a double turn hem for the lining (1cm width) and topstitch it down halfway.
With right sides facing, align the edges of the vent and stitch from the start of the vent to the end of the lining hem.
Press the face fabric at the extension such that the lining lines up with the face fabric at the side seam as shown above. You can see that the lining will not stay flat. This is ok, we will be treating that shortly.
Turn up the skirt hem and secure.
Ok, so remember the lining will not sit flat? Flip the lining for the left side of the skirt away from the face fabric (above image). Do a diagonal snip into the corner of the lining (below image).
Now the lining for the left side of the skirt can lie flat.
Now we do a similar snap into the lining for the right side of the skirt. Flip the lining away from the face fabric (above image). Snip into the corner of the lining (see below image).
Now we can join the left and right linings from the end of the zipper to the start of the vent (see above).
Press the seam open.
Then we join the left and right face fabric from the end of the zipper to the start of the vent (see above).
Press the seam open. The crease will help us in inserting the concealed zipper later.
Now we can do a snip into the corner for the face fabrics (see above)
Align the four layers properly. The right side of the skirt should tuck in nicely into the left side, forming a beautiful vent. Tuck all the seam allowances for the vent in between the face fabric and lining (see below).
Sew across the seam allowances to secure them.
Align the four layers properly to check that the vent lies flat.
The skirt is now ready for the insertion of the concealed zipper. I’ve not gone into details of inserting the zipper in this post, but you can watch the process from my previous video post here.
The zipper is inserted. Check that everything lines up and there is no pull along the Centre Back (CB).
To join the lining to zipper tape, flip all the layers to one side and only flip out the seam allowance of the lining. In this case, i’m doing the right side lining first. Align the edge of the zipper tape to the seam allowance (1.5cm in my case) and stitch about 0.5cm away from the edge of the zipper tape.
Right lining has been attached to the zipper.
Now we do the same for the left side lining.
And the back of the skirt is done (okies, minus the waist darts).
For the remaining of the skirt, the sewing sequence is not too much complicated from an unlined skirt:
Sew all waist darts
Join front lining with back lining at the side seams. Press seams open.
Join front and back face fabric at the side seams. Press seams open.
Attach waistband to skirt.
Finish the hemming for the lining.
Finish the hemming for the face fabric.
The skirt is complete!