Detailed tutorial shows you exactly how to make cheap DIY Outdoor Cushions. Thick, comfy, and waterproof, they’re exactly what you want in your backyard!
Once I’d decided to build an outdoor sofa for my porch, the first thing I went about doing was finding cushions.
Why? Because cushions are expensive.
I wanted to find the cheapest cushions I possibly could, then build my couch to fit those cushions.
After a ton of research, I had a Plan A (and B and C.) I’d start at my local Habitat for Humanity Restore, where they frequently sell used couches for $10, and see if they’d let me take the cushions home for that price, but leave the couch frame behind.
Low and behold, they let me. 30 minutes and $8.75 later, I left the store with a car full of couch cushions ready to be converted into cheap DIY outdoor cushions. Here’s what I did.
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DIY Outdoor Cushions
- Used Couch Cushions– I got mine at the local thrift store. Be sure to check carefully for bedbugs- cheap cushions are not worth spreading an infestation into your home! Additionally, I specifically looked for cushions with zippers, so I could remove the zipper and use it on the new covers. This way, I wouldn’t have to buy zippers!
- Outdoor Fabric– I used duck canvas from Joann’s, which cost me around $30 for 6 yards of fabric.
- Sewing Machine and Matching Thread
Step 1: Determine Size of Cushions
After dragging the cushions into my house from the car, I was left with a sad, dirty pile of used cushions:
I immediately took the fabric off the seat cushions, and measured them.
My cushions were 25″ x 23″ x 5″.
Step 2: Cut Two Primary Fabric Pieces
The cushion cover consists of two different parts: the top piece that covers the top of the cushion and the sides of the cushion, and the bottom piece that covers the bottom.
The two pieces are sewn together on three of the four sides (the fourth side is the zipper) to form the cover.
To determine the size of the top piece of fabric, I added 11 inches to the length and width measurements of the cushions.
This was to account for 10 inches of sides, plus 1 extra inch for seam allowances. For your own cushions, you can use this formula:
Each Dimension of Top Piece of Fabric = (Width/Length of Cushion) + 2(height of cushion) + 1
For my cushion, this came out to be a 36″ x 34″ piece of fabric.
For the bottom piece, I just added 1 inch to the dimensions of the cushion to account for seam allowances. Since my cushion dimension was 25″ x 23″, my bottom piece of fabric was 26″ x 24″.
Step 3: Cut Out Corners
On each corner of the top, larger piece of fabric, I cut out a 5″ x 5″ square. This was the height of my cushion, if you’re working with a different sized cushion, cut out a “r by r” sized square from each corner, with “r” being the height of your cushion.
This accounts for each corner of the cushion.
Step 4: Pin and Sew Corners
Fold over and pin each of the four the corners, right sides together if your fabric has a clear “right” and “wrong” side (mine did not.)
Then take your fabric over to the sewing machine, and sew each of the four corners! After sewing, my fabric looked like this:
Step 5: Pin and Sew Bottom Piece
On three of the four sides, pin the bottom piece to the top piece, right sides together.
Sew the three sides in place. To sew the two corners, when you reach them lift the presser foot up and turn the fabric 90 degrees. Then put the presser foot back down and keep going!
Once the three sides are sewn in place, pin and sew two to three inches on either end of the fourth side. Only a couple inches are necessary; the zipper will go in the middle.
Step 6: Cut Out and Attach Zipper
It’s disclaimer time. In pretty much every sewing post I’ve ever written, I take a moment to stop and tell you how bad I am at sewing.
For this post, that moment has come. Sewing is a means to an end for me, and I’m satisfied with anything that’s “good enough.”
Thus, I have no idea how one actually installs a zipper. I tend to wing it. I know my sewing machine has a “zipper foot,” which I have absolutely never touched, so I know whatever I’m doing is definitely wrong.
If you actually know how to install a zipper, please, use your knowledge and skills correctly. On the other hand, if you also have no idea what you’re doing, and are perfectly happy with “good enough,” keep reading.
I started by cutting out the zipper from the original fabric.
Then I pinned each side of the zipper to one piece of the fourth edge. See picture below.
I also made sure that the zipper part would be on the outside of the cushion cover, while the scrappy fabric part would be on the inside of the cushion cover. In sewing terms, this means I pinned/sewed the wrong side of the duck canvas fabric to the right side of the zipper.
Note that the cushion cover is still turned inside out.
On sides that were not the salvage (yes, I used the salvage. Sue me,) I folded the edge under before pinning to create a little hem so the fabric wouldn’t unravel.
The zipper I’d cut off the original fabric was a little longer than necessary, so I cut it down using normal scissors.
I cut it an inch or so past the opening, so I knew it wasn’t too short.
Then, finally, I sewed the zipper into place (with my normal sewing foot/needle, just like I sewed everything else.)
It was a lot of fabric for the needle to go through; the duck canvas, the thick old fabric, and the zipper fabric, but as long as I went slowly, my sewing machine handled it fine.
I did not sew the ends of the zipper to the fabric. Yes, this is technically bad. But they’ll be tucked inside the cover, and frankly, this is a cushion cover, not a jacket. This zipper won’t get much use, so I expect it’ll be just fine.
And if you’re nervous about what the zipper will look like, here’s a picture of the finished zipper. You can’t tell the ends aren’t sewn in at all.
Step 7: Insert Cushion
Turn your cushion cover right side out, making sure to poke all of the corners out.
Then insert your cushion. If you’re lucky, it’ll fit right in with a little squishing. When I tried to do this, it became readily apparent that there was no way I was going to get my cushion through the small opening easily. So instead, I found this handy video.
Basically, the woman in the video uses upholstery silk to vacuum pack the cushion, then slips the much smaller version into the cushion cover with ease. Since I certainly didn’t have upholstery silk sitting around, I used a trash bag.
I squished the cushion down enough to be able to seal the top around the hose of my vacuum, then turned on the vacuum.
Shockingly enough, this actually worked, and my cushion was soon a scrunched mini-version that slipped right inside the cushion cover.
I unfortunately don’t have any pictures of this, since it was an all-hands-on-deck procedure, but here’s a picture of the cushion in the cushion cover, aka proof this actually worked.
Step 8: Waterproof
Finally, I waterproofed the cushions with waterproofer spray. It took a fair amount of spray to soak the heavy duck fabric, so both cans in the two-pack were necessary. I’ve written a whole post on this, so check it out!
Did the cushions mildew after a long time outside?
No. However, I should mention that my cushions live on a screened-in porch. They definitely get wet occasionally, but they don’t get drenched on a regular basis.
If they were just sitting out in the backyard, I’m not sure how much I’d trust the waterproofer to truly keep things dry. I’d probably bring them in if I knew we were getting a heavy storm.
Did you leave the trash bag inside the cushion?
Actually, yes. It seemed like a pain to remove, and I figured, if anything, it would help keep the cushion dry.
How do you wash the cushion covers?
The easy answer would be: you don’t. Pick a dark or colorful fabric that won’t show dirt as easily.
Since I idiotically picked beige, a year later my cushions are visibly dirty. A steam cleaner would probably do the trick, although I might want to remove the trash bags before I start, lest they melt all over the cushions.
I absolutely loved how these cushions turned out! I’ve laid outside on the couch a couple of times this week, and it’s awesome having truly comfortable furniture to relax on!
Note that the total cost to cover my outdoor sofa was around $60; $8.75 for the upholstery foam/pillow padding, $30 for the fabric, and $20-ish for the waterproofing spray. Just a friendly reminder that although these DIY cushions were super cheap, the price of fabric and waterproofer still upped the total cost a bit.
If you’re wondering about the back pillows, they were made from the same $8.75 couch cushion purchase. I made DIY pillow inserts, then stuffed the pillows into my favorite style of DIY envelope pillow cover. They were much faster to make than the seat cushions!
Finally, if you found this post useful, go ahead and save it to Pinterest so you can find it again later!