Question re flannel seam allowances
 

I'm planning to make a disappearing nine patch from flannel, with a flannel backing as well.
Should I make my seam allowances 1/2 inch for both the front and the backing?

We live in the same region! I always use 1/2" on flannel, but my longarmer tells me it isn't necessary if I'm using good quality flannel. Still can't break the habit.

I do find that some flannels will shred more readily than quilt cottons. Better safe than sorry. The only disadvantage I see is that flannel quilts do become quite heavy.

I prewash all flannel and use a regular 1/4" seam allowance. Never had a problem, but I don't use flannel a lot either, it is just not cold enough here to need it.

I use a lot of flannel, it's one of my favorite fabrics for quilts. I use a regular 1/4" stitch most of the time. I only increase the seam width if making raggy quilts. If you find you have a thin,
Loosely woven flannel, prewash it in hot water & dry it in a regular setting dryer - that should tighten up the weave.

I agree with Jeanne. It seems I always end up make rag quilts with my flannel.

I have made two quilts using flannel, that I can remember. The first was my very first quilt ever - I did not prewash and used 1/4 inch seams. It used three inch squares in a trip around the world, baby quilt. I used warm and natural and flannel backing. I made it for my granddaughter when she was born and she still uses it and she is 11. The second was a flannel and chenille half square triangle quilt for the 6 year old grandson when he was born. Still uses it. Prewashed, used 1/4 inch seams and flannel batting and backing. I didn't have any trouble with the 1/4 inch seams and these quilts have been washed a lot of times and are still going strong.

Here's the update - I prewashed the flannel and decided to use my dual feed 1/4 inch foot. The foot actually stitches a little wide, so I ended up with seam that were a little over 1/4 inch. Top and backing pieced, mounted and ready to quilt. Pictures when I can.

I've always used a 1/4 " seam as well and have not had a problem.
I wonder if using a shorter stitch might solve any potential problems???