When I first started work on making TV291 I had a lot of questions about fabrics and finishing techniques. Because I was being dense, I hadn't noticed the fabric question on the Truly Victorian website, so I sent in an email asking all sorts of questions about fabrics and how much of the finishing needed to be done as the pattern directed. I wasn't really looking forward to flat-lining all my fabric.
Heather McNaughton from Truly Victorian was a really good sport about my slightly grumpy email. She sent me back an email on the same day with a whole bunch of advice about fabrics and period finishing. Anyway, I thought I'd put her letter online for similarly challenged people to read. (If you have a lot of time to dig, you can also check out the Truly Victorian Message Center.)
Thanks so much for your advice Heather! Despite the fact that I didn't have time to do the facing properly the skirt turned out great!
I hope these answers get to you in time to help.
The skirt is flatlined and faced because that is the historical method of finishing 1890's skirt. The flatlining was often accompanied with a stiffener that went 1/2 way up the skirt. I opted to not do that much, in favor of the smaller facings, which are also historically correct. These were all designed to keep a crisp and smooth skirt. the 1890's didn't like skirts that flapped or swayed much. Stiff and heavy is the rule. It really makes a difference, so give it a try.
As far as shortening, you can still use the same facings. Cut the bottom edge off exactly the same as you cut the hem on the skirt, and it will all match. It will be a shorter facing, but should still be adequate, and do the intended job. If you chose, you can omit the facing and do a simple hem, not a problem
By interfacing, do you mean the white standard interfacing used in modern clothing? If so, I would not recommend it. It is not historical, and doesn't move the way a broadcloth lining does.
As far as fabric choices, it really is a matter of personal taste and what is available. It can be anything from a dotted swiss to a canvas, brocade, velvet, silk, stripe, plaid, print, whatever. I don't like to limit peoples choices with my personal preferences. I personally believe sewing is an art form not a science, so there are many ways to get where you want to go. I hate to give absolutes as there really are none. And many places have severe limitations on what is available in the area. I would hate to tell people they needed linen, when all that is available is calico. "How stretchy" is "not stretchy at all." Every fabric has some give to it, and that is fine. But any fabric that is woven with the idea of having stretch is out. Although I have used some stretch twills when there was nothing else available. So anything with lycra, knit, jersey, spandex, velour, etc, is not a good idea.
When to flatline is dependent on what the look you want to achieve. I always flatline skirts if there is no ruffles/trimming on them. It just makes them look better. I usually use broadcloth for all skirts, and twill for bodices. Light summer bodices get broadcloth instead of twill. Loose woven fabrics like satin and brocade should always be flatlined to give support to the weave at the seams. Summer sheers can go without lining for the airy look.
With historical clothing, the understructure is half of the costume. I have learned that more is better, and your fabric can never really have to much structure. I remember 1 woman coming up to me saying "wow, I made 5 versions of the same skirt (TV298). And this last time I followed your instructions and used the linings and facings. You know, it really makes a huge difference. I can't believe I wouldn't do it before now."
You may want to check out the bulletin board on my website. We have a lot of discussions there about just these sorts of question. Everyone has a personal favorite method, and they are very helpful and friendly too. Of course, I answer a lot of question there too.
If you need anything else, please let me know.