Introduction: Waterproof Rolltop Stuff Sack

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Keep your gear and valuables dry while enjoying the great outdoors with a waterproof rolltop stuff sack!

Supplies

  • Sewing Machine
  • Scissors

Materials

  • Waterproof Fabric (see options below)
  • Webbing
  • Buckle
  • Seam sealer (See variants below)
  • Nylon Thread (optional, but more durable)

Waterproof Fabrics Options

Waterproof fabrics are available with a varying durability, waterproof rating (measured as hydrostatic head), and weight. Outdoor gear fabric vendors sell a variety of waterproof fabrics to suit your use case. For this project I am using 1.1oz Silpoly.

Seam Sealer Variants

Silicone Seam Sealer such as SilNet - for Silicone coated fabric
PU Seam Sealer such as Seam Grip - for PU coated fabric

Step 1: Size & Cut the Fabric

Decide on the rough dimensions of your stuff sack when full.


My stuff sack will have the following dimensions:

Side Height: 8"

Bottom Width: 8"

Bottom Depth: 4"

Calculate the size of your fabric cut with the equation below:

Side Seam Allowance: 1"
Rolltop Allowance: 1"
Rolltop Closing Allowance: 2"

Fabric Cut Height: 2 * ( Side Height + Bottom Depth + Rolltop Allowance + Rolltop Closing Allowance )

Fabric Cut Width: Bottom Width + Bottom Depth + ( Side Seam Allowance * 2 )


My fabric will be cut with the dimensions: 30" x 14":
Height: 30" = 2 * ( 8" + 4" + 1" + 2")
Width: 14" = 8" + 4" + 2"


Cut a rectangle from your fabric with your calculated dimensions.

Step 2: Sew the Sides

Fold the fabric in half crosswise, with the "right" face of the fabric facing out.


With the folded edge closest to you, sew a flat felled seam along the right edge of the fabrics:

  1. Starting 1.5 inches from the top of the fabric, sew along the side, roughly 1/4 inch from the fabric edge.
  2. Turn the fabric inside out, such that the "wrong" face of the fabric is facing out. Flatten out the seam with clips or pins.
  3. Sew along the side again, roughly 1/2 inch from the seam edge.
  4. Fold down the flap of fabric you've just created so it is flush against one piece of fabric. Sew along the flap's outer edge to attach it to the side of the stuff sack.

Repeat the steps above on the left edge the fabrics.

Step 3: Sew the Bottom

Line up the bottom shape:

  1. Fold the fabric such that the two side seams are aligned upon each other, along the center of the stuff sack.
  2. Fold the bottom of the stuff sack such that it makes a square shape and pin the corners that are flat against each other.
  3. Measure the size of the desired bottom width along each pinned bottom corner. For my stuff sack this is 4".
  4. Draw a line with marker along the measurement.

Sew the bottom shape in place:

  1. Sew along your drawn line.
  2. Cut the excess corner of fabric, roughly 1 inch away from your seam.
  3. Fold the excess cut fabric towards the center of the bottom, first by 1/2 inch, then again 1/2 inch.
  4. Sew the outside folded edge into the bottom of the stuff sack.

Step 4: Add the Rolltop

Cut the Webbing

Cut two pieces of webbing with the following lengths:

  • The distance from one side seam to the other side seam at the open end of the stuff sack.
  • The same length as above, plus 4 inches.

For my stuff sack I will cut a 12 inch and 16 inch piece of webbing.

Sew the Webbing

  1. Turn the stuff sack inside-out.
  2. Align the shorter piece of webbing along one side of the top edge of fabric.
  3. Fold the fabric and webbing over once, then again.
  4. Sew the length of the webbing, along its inside edge.
  5. Sew the length of the webbing along its outside edge.

Repeat with the other webbing, but keep the additional 2 inches sticking out on either end.


Add the Clip

  1. Turn the stuff sack back right-side out.
  2. Align the two pieces of webbing so they are flush against each other and pin in place.
  3. Sew a vertical bar tack at each end of each webbing overlap.
  4. Feed the excess webbing through one side of the clip and upon the other piece of webbing, pin down.
  5. Sew two bar tacks to attach the excess webbing to the other piece of webbing.

Repeat with the other side of the clip and other side of the webbing.

Step 5: Seam Sealing

Seam sealing prevents water from getting inside your stuff sack through its seam holes.

Do this outside or in a well-ventilated area.


To seam seal your stuff sack:

  1. Turn your stuff sack right side out
  2. Apply seam sealer along each bottom and side seam.
  3. Using a small brush, spread the seam sealer along the seam, ensuring that the it covers the full length of the seam.
  4. Wait at least 4 hours for the seam sealer to dry.
  5. (optional) Sprinkle some talcum powder over the seam sealer to reduce the tackiness.

Step 6: Stuff It!

Your stuff sack is now all ready to be filled. Now load it up and take it out in the rain!