How to Make an Easy Box Cushion
Updated: Mar 5, 2022
AKA The Dog Bed Chronicles: Part 1.
So here's the thing: my dog, Freddie, whom I love very much with all my heart and soul, is now seven (!) and has Decided that sleeping in the bed with my husband and I is just no good anymore. He is Offended any time someone moves a bit. Therefore, he has been sleeping upstairs in his most luxurious dog bed which is in a totally separate room. This would be fine except the bedroom door MUST now be open, should Sir ever wish to come visit the bedroom in the night (otherwise he just scratches at the door).
My solution (please please please work) is to make him a Very Fancy dog bed for the corner of the bedroom.
This will be a two part series - Part 1 (this part) is the making of the box cushion. Part 2 will be a more complex construction in which I construct a tent for the cushion to go into, giving Fred his own private abode.
A Bit About Box Cushions
Box cushions are everywhere. They are on your couch, your window seat, and maybe your kitchen chairs. It can seem a little intimidating to say "I want to make my own cushions," but they're really quite simple.
In this post, I will walk you through how to make a dog bed specifically, but please know that these steps apply to ANY box cushion. I will also try to point out where you can jazz it up a little to make your cushion look more professional (not needed here, because dog bed).
Essentially, box cushions consist of two facing pieces (usually rectangular) bound by two long edging strips, one of which will have a zipper. They can be made in any shape to fit any space.
Q: How difficult is it to make a box cushion?
A: The most difficult bit of the project is turning the corners (I have a trick for this in the tutorial below) and attaching the zipper. If you can sew in a straight line and own a zipper foot, you can probably make this project. As a general statement, I would call a square or rectangular box cushion suitable for beginners who have already completed a few other projects.
Q: What kind of foam is best?
A: There are many types of foam out there, all suited to different types of cushion. I am particularly fond of Foam N' More for their variety, pricing, and well-written explanations which help differentiate between the types of foam they sell. For my window seat project (not pictured here, sorry), I purchased their 3" luxury firm high density foam and have found it very comfortable for long periods of sitting (Freddie is also a fan). For the project shown in this tutorial, I purchased foam from JoAnn Fabrics because there was a sale and I had a coupon, making it very affordable. The foam is not as dense, but is just fine for a dog bed.
As a general guideline, consider where the cushion will live and how often it will be used. For example, a cushion for an patio chair should really use a foam meant to be outdoors as indoor foam could end up harboring mold. If working on a cushion that will be sat on daily, a high density foam would make sense. Take some time to shop around before making your final decision and remember to check the store's return policy in case you change you mind!
Q: Do I really need batting to go over the foam?
A: Strictly speaking, you don't need it, but it will cause the cushion to fill out the cover much more nicely. Without batting or Darcon Wrap, the cover may look a bit saggy and will be prone to wrinkling. Batting also helps to protect the foam from any damage.
Q: Do I need to use foam?
A: Nope! Foam is great for structured cushions, but you can use any sort of stuffing you like. For example, PolyFill, cotton batting, kapok fiber, fabric scraps, or even buckwheat hulls and similar products which I've heard are excellent for meditation and yoga pillows. If you want the durability of foam without the cost, try shredded foam. Shredded foam is much less expensive because it's made from scraps and leftovers. Whatever filling you choose, be sure it's appropriate for the final environment of the cushion (consider mold and insects especially!).
Q: What kind of fabric is best?
A: Similar to the foam, consider where the cushion will live and how often it will be used. Outdoor cushions deserve outdoor fabric - look for UV resistant varieties if the cushion will get a lot of sun. Indoor cushions, like the one in this tutorial, can be made with any sturdy fabric. Home decor fabric is the most common, but you can also use cotton duck, denim, or any fabric with some heft. For this dog bed, I used denim I found on the clearance rack. For help on how much fabric to buy, see below.
Q: How do I get that cording that professional cushions sometimes have at their edges?
A: This type of cording (shown on the cushion in the image to the left) is called welting. If you will be making a lot of welted cushions, consider getting a welting foot for your sewing machine.
To make welting for your project, you will need unfolded bias tape (also called binding tape) and welting cord (also called cotton filler cord if you're at a craft store). I recommend making your own bias tape out of the same fabric used for the cushion. When you make the bias tape, don't fold and press it. You need only cut it out in strips. If you will use a 1/2 inch seam allowance, cut the strips to be 1.5 inches wide.
To make the welting, fold the bias tape in half, stick the cording in there, and then stitch as close to the cording as possible either with a welting foot or a zipper foot. Congrats, now you have welting tape!
I will note in the tutorial below when to attach this to each of the faces.
Q: What materials do I need to make this project?
A: For each cushion, you will need:
A sufficiently large piece of foam appropriate for the cushion's final destination (or a sufficient amount of another type of filling)
Darcon wrap or cotton batting (optional but recommended for foam cushions)
Spray glue (I recommend 3M Super 77 or similar - for foam cushions with batting)
Fabric (see above for considerations on type and below for calculating the amount)
A sewing machine needle appropriate for the fabric (e.g. jeans needle for denim)
Welting cord if desired
Matching thread (choose something sturdy)
An upholstery zipper long enough for the cushion
Chalk / pencil / something to mark fabric with
Pins or hem clips
A rotary cutter is great if you have one
Pinking shears will also be helpful if you have them
Design Your Box Cushion
To begin, we must determine what our final project will look like. This will let us purchase the right amount of materials.
First, decide the shape of your cushion and it's final dimensions. Remember that the foam thickness will determine the height of the cushion.
My dog bed will be 36" by 24" and use 3" foam, so it will be 3" thick. The top and bottom facing will be the same dimensions when the cushion is finished and I am using 1/2" seam allowance. So, add 1" to each direction to get the facing sizes of 37" by 25". Remember there is a top and bottom, so cut 2.
Next is the outer edging which we hope to do in one long strip. Of course, you can also cut it in smaller pieces if needed (no need to drive up fabric costs). To determine its size, decide which end of the cushion will have the zipper (long edge recommended for easier stuffing later, but choose the side that will be hidden), then add together the other three sides. For me, that's 25"+37"+25"=87". Now add 10", this will make the edging wrap all the way around to the back of the cushion, hiding the zipper and making the edging seams easier to sew (see photo below for reference). 87"+10"=97". Height wise, the cushion will be 3" thick, adding 1" for seam allowance gives us 4".
A note here - if you are making a very small cushion, add less than 10" for the long edging. The goal here is to have it wrap around all of the corners by at least a little bit.
Finally, the zipper edge. To get the length, take the length of the side where the zipper will be and subtract 4" (or less for very small cushions). For me, that's 37"-4"=33". To get the height, take the height of the cushion and divide by 2, then add the seam allowance. For me, that's 3"/2 =1.5". Plus my seam allowance (1/2" each side) is 2.5". Remember to cut 2 of these, one for each side of the zipper.
Yes, the edging pieces will overlap. That is intentional as you will see in the tutorial below.
Repeat above for any additional cushions.
Now that you have a sketch of the pieces you will need, you can layout how you will cut them out on your final fabric and determine the amount of fabric to buy. Most home decor fabric is 54" wide, for reference.
If you will use welting cord, find the perimeter of the cushion and multiply it by 2, then add ~16" for safe measure - this is the amount of cording you will need. Check out this helpful calculator to determine how much fabric you will need to make the bias tape (remember it will be 1.5" wide strips).
Once you've got everything ready to go, time to start making!
Ready the Cushion
Because the glue will take some time to dry, I recommend you do this step first.
Start by assembling your materials (foam, glue, batting) in a well-ventilated space.
(Step 1) Cut the foam to size, if needed. In this case, the employee at JoAnn Fabrics who cut my foam was a bit off, so I only had a tad of correcting to do.
To cut the foam, mark your lines with a sharpie and use a bread knife. Start by scoring the foam along the cut line, then go back and do deeper drags to cut the rest of the way through.
You can see my cutting here was not so great, but that's OK because the mistakes will be hidden by the batting.
(Step 2) In the well-ventilated space, shake the glue can, then spray one facing side of the cushion with the glue. Cover with the batting and press lightly to secure. Flip the cushion over, wrapping the batting around one of the long edges. Repeat on the other facing side.
Next, spray the sides of the cushion and wrap the batting over the side edges to cover. Don't worry about excess batting, you'll trim it later. Leave the side that will be zippered empty of batting. It's OK if you forget, but leaving one side bare means there won't be anything for the zipper to snag on later.
This step can be quite sticky, so you may want to wear gloves. If the fumes are a concern, you can also wear a mask.
Leave the cushion to dry and go wash your hands. At this point, I went to start working on the cushion cover. I later came back to finish the cushion prep after the cover was ready.
(Step 3) Check to see the glue is try by pressing onto the batting. If it feels tacky or sticky at all, it's not done drying.
Once the glue is completely dry, trim the excess batting around the edges. It's OK if the batting isn't a super clean job, remember that it will be inside a cushion cover.
Make the Cushion Cover
(Step 1) After pre-washing and pressing your fabric, cut out the pieces you outlined during the design process. Each piece should be cut along the grain of the fabric (not along the bias). You should have 2 facing pieces (top and bottom), 2 short edgings for the zippered side, and 1 long edging for the rest of the sides. Take this last opportunity to give them a good press at the ironing board.
Sewing machine check: Make sure an appropriate needle is installed on your machine before proceeding!
(Step 2) If you will use welting cord, now is the time to attach it to both the top and bottom facings. Starting at the center back of the facing on the right side of the fabric, pin the welting cord so that the "bump" side with the cord on it is towards the center of the cushion. Stitch, leaving the first few inches of the cord unstitched. Sew your way around, being careful when turning the corners (TIP: snip the cording fabric most of the way to get a tight turn). Join the cording where the edges meet. Check out this video by The Funky Little Chair for a few easy ways on how to do this.
Repeat with the other facing piece.
(Step 3) Create the zippered edging side.
Press the seam allowance in on one long edge of each of the 2 zipper edge pieces.
Remember to press it towards the wrong side of the fabric!
Also grab a piece of scrap fabric about 2" wide (or wider) and press one side of it under - this piece will be used as a zipper pull hidey hole. If the steps to include it seem too tricky for you right now, you can just leave it out and hand sew some bar tack stitches at the ends to prevent the zipper pull from running under the seam.
Pin and sew the pressed edge to one side of the zipper, beginning at the bottom of the zipper. Be sure your zipper is centered on the piece if it is shorter than the fabric strip.
As you sew with a zipper foot, the pressed edge should be at the center of the zipper. It will look like it's popping up, but we'll press it down later and, generally, that will make it behave. Either way, remember that this is the side no one but you will ever see.
When you get near the end of the zipper: first, mark where the zipper pull will live, then use the zipper pull to unzip past the foot (make sure the needle is down, then lift the foot up) so you can keep stitching in a straight line.
Take the small scrap from earlier and insert it underneath the edging piece (sandwiched between the zipper and the edging). Make sure the pressed end of the scrap is perpendicular to the zipper edging.
Continue to stitch to the end of the zipper and then the end of the edging piece, remembering to backstitch at the end.
Now repeat with the other half of the edging facing, again starting at the bottom of the zipper. This means you will need to adjust the zipper foot. Line the pressed side up with the edge of the piece which is already sewn onto the zipper (they will meet at the zipper center).
Notice that, again, the fabric wants to pop up after being stitched - don't worry about that, we'll press it in a few minutes and it will (mostly) behave.
When you near the end of the zipper, backstitch and stop the seam a few inches before the end. It's time to fuss with the zipper pull housing.
Pop the scrap fabric up and over the zipper pull and pin to the other side of the zipper. TEST that there is enough space for the zipper pull by holding the end of the zipper with one hand and un-zipping and re-zipping the zipper with the other hand. If it's tight, unpin and pop the scrap up a bit more.
Once satisfied with the height of the zipper pull housing, pin down the edging piece so that it lies on top of the scrap piece, next to the zipper pull, and then returns to meet the other edging piece by the end of the strip. It's OK if the pieces don't line up perfectly at the end. Unzip the zipper and complete the seam.
On the wrong side of the zippered edge (now finished), trim the excess from the scrap piece that made the zipper pull housing. This will prevent it from getting into the edging seam later which would make the seam hefty and more difficult to work with.
Finally, complete the zippered edge by pressing the fabric over the zipper so that it lies flat - the fabric edges should meet at the center of the zipper.
That was the trickiest part of the cushion - promise! Now we do the rest.
(Step 4) IF the fabric you will use for the rest of the edging is NOT one very long strip, now is the time to sew the smaller strips together, right sides facing. Press the seams open before moving on.
(Step 5) Attach the long edging to the top and bottom faces.
To begin this step, find and mark the centers of the front sides of both facing pieces and the center of the long edging strip.
Match the centers of one of the facings and the long edging strip right sides facing and pin the edging all the way around the facing. MARK, either with chalk/pencil or a double pin set (literally just two pins instead of one) that you will STOP sewing 4 to 5 inches before the end of each side of the edging. This stop point should still be after turning the last corner.
Sew around, starting at the center marking and adjusting the edging as needed so lie flush with the facing.
To turn the corners:
Stitch to the turning point and put the needle down. Lift the presser foot and use a pair of snips to cut a diagonal notch into the corner of the edging strip. Pull the edging around the corner so the sides line up and "pop" the edging up with one hand so the fabric behaves at the needle (no puckers under the seam). Put the foot down and continue sewing. This gets easier the more you do it, promise.
Finish the facing seam, remembering to STOP 4 to 5 inches before the ends of the edging strip, after turning the last corner. Repeat from the center of the facing, going the other direction so that the edging strip is completely attached to one facing.
Repeat with the other facing. You will now have a cushion cover with 3 sides and a little bit of a 4th side at either end.
Trim the corners and the seams just completed. I like to use pinking shears here. Don't trim too closely, we're just cutting down on the bulk at the corners.
(Step 6) Sew the zipper edging to the top and bottom facing.
As with the long edging strip, start by finding and marking the centers of the zipper edging and both facing pieces.
Line these up and pin the zipper edging to the facing, right sides facing.
Sew the zipper edging to the top and bottom facing, beginning the seams at the center marks and STOPPING 4 to 5 inches before the end of the zipper facing.
When finished, you'll have a cushion cover with 4 sides but the edging pieces are not yet connected.
(Step 7) Close the cushion edging.
Pin or clip the edging pieces to both facings until the long edging meets the zipper edging. Then pin the ends of the edging pieces together (right sides facing).
Be careful of the zipper - you can stitch over a zipper (CAREFULLY and SLOWLY, I hand turn my machine for this), but it's much easier to avoid the requirement.
Mark where the edging ends meet at the corners with the facing, i.e. where the edging ends seam needs to be for the edging to be completely flush with the facing piece. Make the same mark on the other side of the edging strips.
Unpin or unclip the edging from the facings, but leave the edging ends pinned together. Draw a line between the top and bottom markings.
If the line isn't quite straight, go ahead and adjust a bit until it is.
Sew along the line at least twice, backstitching at the ends. This will be the weakest seam and where the cushion cover is most likely to rip.
Repeat at the other point where the zipper edging meets the long edging.
Trim these edging seams and press them open.
The ironing here can be a bit fiddly - I like to use a tailor's sausage under the edging strips so the rest of the cushion cover stays untouched.
If you don't have a tailor's sausage, a rolled up towel or heat-appropriate wad of fabric does the job just fine.
(Step 8) Finish the cushion cover.
The edging should now be perfectly flush with both facing pieces.
Pin or clip the edging to the facing, making sure those short seams just pressed stay open (otherwise there will be one very bulky bit of seam).
Stitch to complete the seams connecting the facing to the edging strips.
Repeat on the other side of the same strip and then again at the other side of the zippered edging.
The cushion cover should now be complete and totally inside out with NO gaps in the seams. Trim these last seams.
The cover is now finished! Unzip the zipper by either carefully pushing/prodding the zipper pull from the wrong side OR by gripping the zipper pull tab through the fabric. Once the zippered edge is open, turn the cushion cover right side out. Check for gaps and fix them if you find any. Now is also a good time to sew some bar tacks at the ends of the zipper.
Put it All Together
Now that the cushion is ready to go and the cushion cover is completed, it's time to put the cushion cover onto the cushion.
This part is tricky and much easier if you have a second person to help you. There is only one picture for this part because I would need a third person to take them and there are only two people in our house - sorry. This is the method I use:
(Step 1) Place the cushion cover onto one corner of the cushion and line the corners up as much as possible. Note that the side of the cushion without the batting is where the zippered edge of the cushion cover should end up (no batting for the zipper to snag on).
(Step 2) Roll the rest of the cushion long-ways (hamburger style) so it's sort of a cushion burrito. One person holds the cushion burrito while the other person pulls the cover over the rest of the cushion.
(Step 3) One person HOLDs the edges of the zipper with both hands (this is where it will want to tear) while the other person slowly releases the cushion burrito, grabbing and shoving the cushion corners into the corners of the cushion cover.
(Step 4) Once the cushion is in the cover enough that the cover is no longer in danger of ripping, let go of the cushion cover. Fuss with the cushion cover, again shoving cushion corners into cushion cover corners, until the cover is where it needs to be. It will be tight because of the batting, but that's what you want. Zip the cushion cover closed.
Done! Revel in the fact that you made something for half the price (or less) than a store would regularly charge. Your cushion can now go live in its home!
A tip: if the cushion will be living on a slippery surface (e.g. the floor, a windowsill, etc.), you can use non-slip kitchen cabinet liner underneath the cushion to keep it in place. This is excellent for pet items and homes with small children.
I hope you enjoyed this tutorial - remember to like this post, leave a comment below, and fill out the subscription box at the bottom of the page to make sure you never miss a post. Happy sewing!