Figuring for the Quilt Back

The backing fabric for the quilt must be at least a little bigger than the quilt top. The reason for this is that when the quilt is being quilted—by hand or machine—it is possible that the backing and top will not be stretched identically on the quilting frame. If, after the quilt is quilted, the edges are uneven, you may then trim the backing even with the top before binding. If the quilt is to be machine quilted on a long-arm quilting machine, the backing should be at least 3” larger all around than the quilt top. The quilter may require more than 3”, so confirm that with her or him before buying the backing.

There are many ways to piece a back for a quilt. The one presented here is a simple way to figure that may result in quite a bit of leftover fabric, depending on the size of your quilt. Your local quilt shop staff should be able to help you confirm your figures or help you choose a different type backing if you want to do something out of the ordinary, or if you want to avoid having any extra backing fabric.

You will be trimming away the selvage of the fabric for the backing. If left in the quilt back seams, it will be difficult to quilt where the selvage lies. For the purpose of these directions, we will assume you are using fabric that is labeled 44/45”-wide. HOWEVER, many quilting cottons actually have only 40-42” of useable surface in their width. Measure the actual width when you are at the quilt store, or, if you are ordering online, assume that the fabric will be 40” wide after removing the selvages.

Measure your quilt. The upper and lower edges should be identical in measurement, and the left-hand and right-hand sides should be equal to each other. If they are not, use the larger number as you figure for the backing.

It is considered best by many quilters to have the length of the fabric running along the length of the quilt because the fabric is more stable in this direction. To the lengthwise measurement of the quilt top, add 6”. Now consider how many 40”-wide pieces you will need across the width for the back. Since the backing needs to be 3” wider all around than the quilt top, add 6” to the finished width measurement of the quilt top. If the sum is larger than 40” (the width of the fabric for the back), you will need a second, and possibly even a third piece of fabric for the back. Below is an EXAMPLE of what to cut for backing for a quilt top that measures 85” X 98”.

40"

120"

The total yards for the backing would be figured in lengthwise inches first—104 + 104 + 104 = 312—which equals 8 ⅔ yards. I would recommend purchasing 8 ¾ yards for the above example.