Interlining is an extra layer of lining that you add to your garment to add warmth and insulation. It is sewn to the lining itself before the lining is attached to the garment.
After a lot of research I decided to use thinsulate interlining from 3M. It’s what Jcrew and almost all the large outdoor sports clothing companies use as their interlining, so I figure it must be awesome! Basically it looks a lot like quilting batting I guess, but it supposedly provides 50% more warmth than goose down (yes please!!).
Since I’m lining with fleece and it’s more than a little thick, I didn’t want to add extra bulk to the seams with the interlining, so I cut the interlining pieces to have no seam allowance. That way, the pieces should butt closely up to each other when attached to the lining, but not overlap. I used a large zig zag stitch to attach it to the fleece, firstly because it’s very puffy and fiberous and hard to sew, but also because fleece is a little hard to keep control of too. After looking into what other people have done when attaching interlining, it seems that removing the seam allowance and zig zagging is a very common method.
For the sleeves I attached the interlining pieces to the lining pieces before attaching the sleeve linings to the rest of the garment or the rest of the lining. The reason I did this is simply because it’s almost impossible to sew along a sleeve once it’s been closed up! As a side note I’m not sure if you recall me saying before, but I’m using a satin flannel lining in the sleeves not fleece, so that the sleeves don’t get too bulky and I can slip my arms in easily without getting all static-y.
However for the main body of the coat I decided to attach the interling after I’d sewn all the lining pieces to each other. The reason I did this, is that I learnt from the sleeves that when the interlining is already attached to the lining, it’s difficult to sew next to it without slipping when sewing the lining pieces. It was frustrating. Plus with the fleece I couldn’t press the lining seams open very effectively. So what I opted to do was pin open the seams then place the interlining over the top and zig zag on the edge of the interlining. This attached the interlining perfectly, but also served the function of keeping the lining seams flat and open.
I apologize that the pictures probably don’t show this very well, but unfortunately black is incredibly difficult to photograph.
Some words of caution about thinsulate as interlining:
- It is obviously stiff as it’s an insulation, and so is really best suited to structured coats. That’s perfect for me as I want my coat to be nicely framed and structured, but if you are looking for more of a drapey loose style coat, this might not work for you. You may end up with a tent! But then again, I don’t think those of us in really cold climates can really wear drapey flowing coats practically anyway!
- It measures a good 5mm thick when uncompressed and about 1-2mm when pressed between fingers. So it adds a significant amount of bulk to the garment. I cut my coat a size larger than I would a suit jacket to accommodate this and it wasn’t quite enough as I had forgotten about the extra thickness of the fleece (I blame this on sewing when sick, note to self, do not sew when sick!). In hindsight it would have been better to cut the jacket a size and a half or maybe 2 sizes larger to accommodate the fleece lining and thinsulate interlining, and I would have saved myself the trouble of having to take apart my jacket and sew it back together with smaller seam allowances to get more room.
- You are obviously going to want to attach your interlining to the wrong side of the lining, that way when you attach the lining to the main garment, the interlining is sandwiched in between the lining and the fashion fabric.
Previous posts in my Coat Construction series:
Upcoming posts in my Coat Construction series:
Part 4, Working with commercial patterns (AKA my standard alterations)
Part 5, The big reveal! (Hopefully soon!)