
I knew I would dread the job of cutting and sewing all the sashing strips to my Jane blocks if I waited until all the blocks were finished. So I decided in the beginning that I would sash the blocks a few rows at a time once I completed them.
PLEASE NOTE:The instructions I'm providing below are my own personal method of assembly - I'm sure there are other ways to create your sashing but this is what works best for ME!
There is a 1/2" sashing strip between each of the blocks in all the rows A-M and a 1/4" sashing around the outside edges (the border between the square blocks and triangles).
Measurement terms = .25 is a quarter inch, .5 is a half inch, .75 is three quarters of an inch. So...I cut one inch strips of fabric by the length of my background fabric (selvage to selvage)
From those one inch strips I cut fairly equal amounts of 1"x5" sections and 1" x 5.5" sections. I also cut a several pieces of fabric that measured 1" x 5.75".
Each block will have a 5" sashing strip sewn to the
RIGHT side and then a 5.5" sashing strip sewn to the
BOTTOM of the block. ALL of these blocks should now measure 5.5" square!

I found it easiest to pile my blocks in numeric order by row...Row A, Row B, Row C with block 1 at the top and block 13 at the bottom of the pile.
NEXT... Pull out Block 13 (it should be the bottom/last block of each pile)
Trim a quarter inch off of the
RIGHT side sashing. All of your A-M blocks that are number 13 should now measure 5.25" across by 5.5" down (top to bottom) This narrow edge makes up the quarter inch border between the square blocks and triangle section.
NEXT...Block #1 of EACH row will need a narrow border sashing on the LEFT side of it's block as well. Sew a 3rd sashing strip to this block - 1" x 5.5" strip to the left side of the block. Press and trim off a quarter inch. Block #1 should now measure 5.75" across by 5.5" down.
NEXT... These instructions are for
EACH block of ROW A and ONLY Row A. You will add a final strip of fabric to the TOP of each block and trim off a quarter inch.
Block
#A1 will measure 5.75" square and have sashing on all 4 sides of it. Blocks
A2-A12 will have 3 pieces of sashing and measure 5.5" across x 5.75" down. Block
A13 will have 3 sashing pieces also (narrow on top & side and normal on the bottom) this block will measure 5.25" across x 5.75" down.

Special instructions for ROW M: You will need to trim the BOTTOM sashing piece a quarter inch on EACH block of this row to create the narrower 1/2" measure (quarter inch border when sewn to the triangle sashing.
I hope you find this a helpful start to sashing your Jane Blocks!
every Quilt tells a story...