I altered her tutorial just a bit and made my own box pleat curtain.
Box pleat curtain tutorial.
6 30 it should say lining width face fabric width 6 inches instead of 3 inches.
Return leading edge 4 for sewing the sides.
So this is how i did my math.
Get the fabric supplies you need at onlinefabricstore.
She does a great job describing how to measure how much fabric you will need with the addition of the pleats hems etc.
If you are mounting your curtain on a 1 4 board you need to add 5 for the ends of the board and 8 for the pleat in the middle.
Pin your pleats so they measure 8 inches and top stitch 8 inches down on both sides of each pleat making sure to back tack at the bottom.
My window is 46 wide.
3 5 3 5 4 11.
Once you have cut your fabric lay the ride side of your drapery fabric down on top of your lining.
We factored in 8 per pleat an additional 3 on each side for the depth of the board to wrap around the return or the side of the board 1 2 for the 1 4 hem on each side and about a 1 2 for each end to wrap around the back of the board equaling 65 5 total in length.
Press all the pleats flat with an iron creating a 3 inch pleat so that the seam is behind the exact center of the pleat.
My board was 42 wide.
We decided on 2 pleats so 3 sections of flat fabric.
For my curtain i only wanted 1 pleat.