Pencil skirts are tight. This limits your movement quite a bit. More so, when you try to sit down, the skirt may try to pull itself off your waist, or, when you get back up, stay quite high on your bum. Lining the skirt will make it move a lot easier around your curves, and thereby make it easier for you to move.
Adding lining can be done by creating a slightly shorter front and back piece, that has some extra fabric in the middle. The extra fabric makes it easier for the lining to move. One inch for each of the front and back pieces is enough. You can either make a box pleat in the front and back, or add the extra fabric where the darts are. You do not need to sew darts in the lining fabric. Just a pleat at the dart position will be fine.
A waistband is optional on Penelope. If you omit it, there will be quite some stress on the top of the zipper. Make sure your zipper is up to the task. An invisible zipper might not be the best option then, since they can’t always take that much strain.
Without the zipper it will be impossible to get in and out of the skirt. So it should be at least the length from your waist to the largest part of your bum. Longer will make it easier to put the skirt on and off. Don’t use one that’s too long, because the part of the seam where the zipper is behaves differently than the part without it, and you want to try to make it invisible also in movement.
Traditionally, an invisible zipper is used in a pencil skirt. Lately there has been a trend to use zippers that are right in the open. Sometimes even from contrasting fabric. Choose what works for you in the style you’re going for. Be creative (or not)! You might want to opt for an alternative option if your fabric is on the heavier side.
A vent in the back is optional with Penelope. It will allow you to walk a lot easier than if you make the skirt without it. The vent also influences where the zipper will be located. If you choose to have no vent, the default zipper location is on the side seam, and the back will be cut-on-fold. With the vent, there has to be a seam in the back piece, and the zipper will be located on that seam.
Darts are used to compensate for the difference between your waist and seat measurements. Depending on this difference, there can be two darts, one dart, or no darts at all. More darts make for a potentially better fit. But if the amount of fabric that the dart will take in becomes too small, the number of darts will be reduced. Otherwise it would be very difficult to sew the darts, and they would probably become rather unsightly. Some of the difference will be taken in by the side seam, and if the difference is small, no darts will be included in the front and back pieces.
We’re not going into a full explanation here on how to create all the individual details that make up a pencil skirt. We assume that you know how to sew a dart, insert an invisible zipper, make a vent, etc. If not, there are numerous excellent articles available on the web, both in writen form, and on video. If you do get stuck, you can always reach out to other FreeSewers.
First, sew all the darts. You want to press them towards the back. So for the back piece, that means you press boths sides towards eachother. For the front piece, just the opposite.
The next thing you want to do is sew the seam that has the zipper, and insert the zipper into it. Follow the procedure that is appropriate for the type of zipper you’re using.
Sew up both the side seams.
Your next step depends on whether you have a vent and lining. If you’re including a lining, now is the time to make it. The lining is made the same way that the rest of the skirt is made, with two exceptions; the darts are just pleats, and they have more ‘ease’ included. How you distribute this ‘ease’ is up to you. You can add it to the dart pleats, add another dart pleat, or make a box pleat in the middle.
Of course, if you include a lining, you have to include this in the way you’ve finished your zipper. And connect it to the vent, if your skirt has one of those.
Next is attaching the waistband if your version has one. First fold it double along the long side and press. Add your interfacing. Sew it to the right side of the fabric. Then turn it over and press the seam into the waistband. Now use the stitch-in-the-ditch technique to finish the waistband. Add your choice of closure.
All that is left now is to hem the skirt.