If you’re making a traditional jacket, then you’re safe to go by the fabric recommendations on the back of the pattern envelope, maybe adding just a little more in case you’ve got a significant plaid to match or a particularly loosely woven fabric that might fray.
But – if you’d like to go the route of the traditional Classic French Jacket – then you’re going to have to do a little bit of simple calculating.
As you may know, that path involves big seam allowances, quilting, three-piece sleeves, the lining seams finished by hand…..it’s a different process, and a slightly different layout.
The first thing you need to do is figure out how long you want your jacket to be, and how long you want the sleeves to be. Then a little simple math will tell you how much fabric to get. You’ll need two jacket lengths and one sleeve length, plus a bit more for hem and seam allowances.
Let’s say you want a jacket that measures 26” from the shoulders. Alright, then – 26” plus 2” for a hem allowance and 3” for seam allowances, so that’s 31”. 31” times 2 takes you to 62”. Then you need to add the sleeve length – let’s say 22” – but let’s add the hem and seam allowances, so now we’re at 27”. So, that’s 62” + 27”, for a total of 89”. Well, 2 1/2 yards is 90”, so that’s what I’d get.
So, why calculate this way? Because when we make the jacket using the quilting and big seam allowances (at least 2”), we can only fit about 5 pieces per width. And we’ve got 13 pieces to accommodate: 2 center fronts, 2 side fronts, 2 side backs, 1 center back, 6 sleeves pieces (3 per sleeve). So, that adds up to 13. Plus pockets. So the layout looks something like this:

Of course, there are variables in size and matching requirements, but this should get you started.
If you would like to know more about making a traditional or French jacket, click here to visit couture sewing educator, Susan Khalje’s website.
Written for Linton Tweeds by Susan Khalje.