Introduction: Lightweight Flannel Sleeping Bag (Machine Washable!)

About: Creative Technologist and Craftswoman

For the "Sew Fast Speed Challenge" I wanted to put together a project that is both useful and can be completed in an afternoon!

This lightweight sleeping bag can be used for sleep-overs, back yard adventures, camping trips, on it's own, or as a sleeping bag liner, anytime you need an extra bit of coziness. The best part, unlike a full size sleeping bag, you can easily throw this in the washing machine and dryer at home.

I used the full width of the fabric to keep things simple, so the finished size of the bag when zipped up is about 40" x 70"

It is super easy to adjust the dimensions to make it longer for tall folks, or smaller in both dimensions by cutting the fabric down. Just make sure to adjust the length of your zipper accordingly.


Materials for Sleeping Bag

  • 8.5 yards of Flannel (1-3 colors depending on preference)
  • Zipper 98"-100" long (if you select a sleeping bag zipper, the bag can be reversible)
  • All Purpose Sewing Thread (or heavier if you prefer)

Materials for Retaining/Carrying Strap

  • Synthetic Webbing (I used 1.5" Lightweight Polypropylene)
  • 2 D-rings with same internal width as webbing
  • 2 Rounded Tri-glide Slides with same internal width as webbing
  • 2 Spring Buckle Lobster Clasps with same internal width as webbing
  • Heavy duty nylon thread


  • Sewing Machine with zipper foot
  • Scissors
  • Small Needle Nose Pliers
  • Sewing Pins
  • Measuring Tape
  • Candle or Lighter for melting ends of zipper, webbing and nylon thread

Step 1: Select, Purchase, Pre-wash, and Trim Fabric

Joann Fabric frequently puts their Super Snuggle Flannel on sale. I got all the material for both of the bags I made for $2.99-$3.99 a yard for the standard 43" wide, 100% Cotton Flannel, so highly recommend keeping an eye out for sales. Make sure to pre-wash and dry your fabric before sewing as it will shrink some. I like to trim up the edges too before beginning sewing to keep everything a little neater. There are several options for how many fabric colors/patterns you can choose for this tutorial.


1 Color/Print Fabric (easiest)

This will need to be a "non directional" print so top border isn't upside down on one side.

Cut List

  • 2 pieces 2yds long
  • 2 piece 2.25yds long


2 Colors/Prints Fabric: Option 1 (This option is the main example shown in this Instructable)
This option uses one color or print for the outer layer and a second color or print for the inner layer and the top boarder. The fabric selected for the inner layer needs to be a "non directional" print so top border isn't upside down when finished.

Cut List

  • 2 pieces of outer layer color/print at 2yds long
  • 2 piece of inner layer color/print at 2.25yds long


2 Colors/Prints Fabric: Option 2 (This is the alternate shown in the attaching Top Boarder step)

If choosing a print instead of a solid color for the top border, make sure to choose a "non directional" print so it is not upside down on one side.

Cut List

  • 4 pieces of main color/print at 2yds long
  • 1 pieces of top border color/print at 1/2yd long


3 Colors/Prints (Not shown)

For this option, select one color or print for outer layer, a second for inner layer, and a third for the top border. If choosing a print instead of a solid color for the top boarder, make sure to choose a "non directional" print so it is not upside down on one side.

Cut List

  • 2 pieces of outer color/print at 2yds long
  • 2 pieces of inner color/print at 2yds long
  • 1 pieces of top border color/print at 1/2yd long

Step 2: Assemble Inner and Outer Layers

Assembling Inner Layer and Outer Layer

  • With right sides of the two matching pieces of fabric facing, align pattern elements, if necessary, by adding extra pins along the edge
  • Sew the two pieces together on the long edge with a 1/2" seam allowance
  • Unfold
  • Fold seam allowance to one side and "under-stitch" sewing with right side of fabric up to secure to one side

Step 3: Trim

Trim ends if they are offset like mine due to pattern alignment. I used the printed stripes as a guide.

Align the inner and outer layers with right sides facing each other, and add a few pins at the bottom corners.

Measure and mark 3" from bottom corners only, and cut a straight line through both layers between the two marks. This is will allow the zipper to make a smooth curve around the corner.

Pin the layers back together at the trimmed corners.

Step 4: Prepair Zipper

If you are using a zipper that is already finished on both ends and the correct length, you can skip this step. I'm using by-the-yard #5 zipper, and have to install the hardware.

  • Using a small pair of pliers, remove 5 teeth from bottom and 2 teeth from top on both sides of the zipper
  • Align and crimp zipper latch slider retainer on one side of zipper, and insertion pin on the other
  • Use a flame to melt cut ends of zipper tape
  • Thread the zipper pull down the piece with the retainer and test the functionality
  • Crimp zipper stop on one side of zipper (you can save this till the end)

I left the other zipper stop off so the zipper pull can be removed during construction as it has a nasty habit of getting in the way and causing problems.

Step 5: Pin and Sew Zipper in Place

With the teeth facing in, pin the bottom of zipper ends between inner and outer layers 3/4" away from the center seam and continue pinning around the whole outer edge.

When you get to the corners, use extra pins to make the curve as smooth as possible. I found that pinning it in place to one layer first to work well.

Put the Zipper Foot on your sewing machine. There are several different types, so refer to instructions for your specific machine. If yours looks like mine, attach as shown.

Sew as close to the zipper teeth as possible by feeling where it is and lightly pushing it against the foot as you sew.

Back stitch at the beginning and end of the zipper.

Step 6: Attach Edging (two Methods)

Method One

For this option, the inner layer is about 9" longer than the outer layer.

Fold both layers down and pin right sides together along the whole top edge.

Sew the whole length with a 1/2" seam allowance

Carefully pull the whole project right side out through on of the openings at the top


Method Two

for this option, the inner and outer layers are the same length.

cut our border color in half length wise

pin right sides together along one of the short edges

sew along pinned edge with 1/2" seam allowance

open, pin fold seam allowance under to one side and stitch in place

Carefully pull the whole project right side out through on of the openings at the top

Step 7: Test Zipper and Pin All Openings

Slide the zipper pull all the way down to the slide retainer

Insert the other side of the zipper and zip all the way up to the top to test function. If there are any parts of the seam that somehow overlapped the zipper teeth and are preventing it from sliding smoothly, trip them off.

Remove zipper pull so it doesn't get in the way

Fold in the raw edges between the two bottom edges of the zipper and pin

Fold the seam allowance of the where inner layer is attached to the outer layer to form the top boarder up and pin in place

Fold in the raw edges of the openings at the top and pin

Step 8: Stitch to Secure Zipper and Fininsh

Pull the zipper out from between the inner and outer layers making sure that no fabric overlaps the zipper teeth, and at least pin any places where the fabric is misbehaving.

Using zipper foot sew as close to the edge as you can along the pinned top opening, the stitch fabric in place along the edge of the zipper all the way around the whole project.

Stitch along the top to secure seam allowance in place

Reattach the zipper pull, then crimp on the zipper stop

Step 9: Quilt

Quilting adds stability to the design to keep fabric from getting caught up in the zipper and prevents it from getting all weirdly bunched up when you wash it.

There isn't really a right or wrong way to do this step. Depending on the fabric pattern you chose and personal preference, you can sew seams across the whole project like I did, or sew a few shapes throughout with a sewing machine or by hand. I chose to run a wide zigzag stitch through every other red checkered stripe, and one down the center-line from the top border down to where the zippers meet.

Unzip and lay out the whole project (you may have to do this on the floor if you don't have a big work table), and smooth out both layers as much as possible so there aren't wrinkles and bunches in the fabric on either side. Add a bunch of sewing pins to keep the layers in place while you sew. If you sew across the whole width of the project, pull slightly outward on both sides to keep the layers from bunching and puckering too much.

Step 10: Make Strap

Cut List

  • 1 piece of webbing at 12" for handle
  • 2 pieces of webbing at 32" for straps


  • Carefully melt the ends of all the cut webbing pieces with a flame to prevent them from unraveling
  • Thread one end of a strap webbing over center bar of a Tri-glide Slider and pin leaving a 1.5" tail
  • Sew a few seams over the tail to secure ( I used zipper foot to get close to the the hardware)
  • Thread free end of strap webbing through the lobster clasp and back through the Tri-glide slider
  • Repeat all for second strap
  • Thread free end of one strap through D-ring and sandwich the piece of handle webbing between the strap and the tail
  • Sew several seams to secure the D-ring and handle webbing to the strap
  • Repeat last two steps for second strap
  • Trim all threads leaving a short tail and melt with a flame to secure (I after each attachment to keep things neat)

Step 11: Enjoy!!!

All done!!!

If you make two, you can then zip them together to make a super-size snuggle bag.

Please share pictures if you make your own, I would love to see your creativity!

Sew Fast Speed Challenge

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Sew Fast Speed Challenge