Planning the Quilt Back
The quilt backing needs to be larger than the quilt top to allow extra for fabric that is taken up during quilting and for stabilization when using a quilting frame. Always add 8" to both the length and width measurements so you have an extra 4" of fabric all around.
Trim off the selvage of all backing fabrics. The selvage edge is tighter than the rest of the yardage and can cause puckering or inward curving in your finished quilt if it is used as a part of the backing.
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.
WARNING: 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.
Determining Backing Yardage
Download the following info in a handy printable chart here.
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First, figure out your backing yardage based on the size of your quilt top. You can piece together backing fabric using horizontal and vertical seams and using different configurations, so following the guide below will help you figure out which way uses the least amount of fabric for your preferred piecing method.
For Quilts Less Than 34" in Width and Length
For a very small quilt that has either a width or length of less than 34", you can use a single piece of 42"-wide fabric for the backing. This width will cover the 34" dimension plus the additional 8".
- Quilt top dimension + 8". Divide by 36" to determine the yardage necessary.
- Example for a 28" square quilt top. 28" + 8 = 36". 36" divded by 36" = 1 yard.
For Quilts 40" to 60" in Width
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.
- Quilt top width x 2 + 12. Divide by 36" to determine yardage.
- Example for a 47x74" quilt top: 47" x 2 = 94". 94" + 12 =106". 106" divided by 36" = 3 yards.
TIP: Manufacturers offer fabrics in widths of 60", 90", and 108", but they are available in a limited color and design assortment.
For Quilts 61" to 80" in Width
If your quilt is wider than 60", you may use one or two vertical seams to piece the backing.
- Quilt top length x 2 + 12. Divide by 36" to determine yardage.
- Example for a 70x84" quilt top: 84" x 2 = 168". 168" + 12 =180". 180" divided by 36" = 5 yards.
For Quilts 81" to 120" in Width
A quilt 81 to 120" requires a backing that is pieced with vertical seams.
- Quilt top length x 3 + 18. Divide by 36" to determine yardage.
- Example for a 95x110" quilt top: 110" x 3 = 330". 330" + 18 =348". 348" divided by 36" = 9-2/3 yards.
Tips for Choosing and Preparing a Quilt Backing
- Cut and piece the quilt backing larger than the quilt top, adding at least 8" to both the length and width measurements.
- If you’re concerned about the quality of your hand or machine quilting, choose a busy print that will camouflage your stitches.
- A pieced backing with many seams is easier to quilt by machine than by hand.
- Choose fabrics with the same care requirements as the quilt top. If fabrics in the quilt top were preshrunk, fabrics for the quilt backing should be, too.