Planning the Quilt Back
You can piece leftover fabrics from the quilt top or from an entirely different quilt project. This is especially charming when you are making a reproduction or historical quilt.
Like batting, the backing needs to be larger than the quilt top. This allows for the fabric that is taken up during the quilting and for stabilization when using a quilting frame. Always add 6" to both the length and width measurements so you have an extra 3" all around.
Don’t forget to trim off the selvedge edge of your fabric. Leaving it on will cause your quilt backing to pucker or curve inward in the finished quilt.
If your quilt top is wider or longer than the width or length of your backing fabric, you will need to piece the backing. If seams are necessary, you need to decide whether your want them to be horizontal or vertical on the back of the quilt.
If your quilt is 40 to 60" wide, horizontal seams save on yardage. If your quilt is wider than 60", you may use one or two vertical seams. A quilt 81 to 120" requires a backing that is pieced with vertical seams.
The quilt top’s measurement determines how many pieces are in the backing. Standard calculations assume 42" of usable fabric can be cut from 44/45"-wide fabric. Some manufacturers offer 60"-, 90"-, or 108"-wide fabrics, but the color selection is limited.
Backing fabrics should have the same care requirements as the quilt top. It should be preshrunk if the quilt top fabrics were. Although muslin is an inexpensive option for a quilt back, keep in mind that it shows every quilting detail and does little to enhance the beauty of your finished quilt. Remember--you will see the back of the quilt when you’re using it. A coordinated backing offers more eye appeal.
Bed sheets for quilt backings aren’t recommended! Although it’s tempting to use a bed sheet because of its size, sheets don’t make good quilt backs. The thread count is much higher in sheeting than in common quilting fabric. The tighter weave causes the needle to break the sheet’s threads when it pierces through, rather than pushing between the threads as it does with quilting fabric. It leaves holes and diminishes the stability of the sheet.
To piece your quilt backing, use 1/2" seam allowances for added stability. Sew the pieces together along a pair of long edges. Press the seam allowances open.