Make Your Own Cushion: Irregularly Shaped Cushion

SKU: X-HT-300686



If you have an oddly shaped space, like a window seat or a sleeping area in your boat or camper, that won't fit a typical square or rectangular cushion, you're in luck! This video tutorial will teach you how to make an irregularly shaped cushion to fit any space. This tutorial is part of our Cushion Masterclass DIY series. We're teaching you the most popular ways to make your own cushion cover. Let's get into today's tutorial!

If you think this is above your sewing skill level — don't worry. We've made this technique even easier by eliminating the boxing strip around the cushion. Traditional cushions are made by sewing a boxing strip to the top and bottom plates, but not our method. We'll show you how to make an irregularly shaped cushion without a boxing strip, making this a very quick and easy project that any DIYer can tackle.

The first step is to cut our foam to the specific shape and size we need. For this cushion shape, you need to cut your foam 1/4-inch larger on all sides than your desired finished cushion size. Sailrite® stocks high-quality CushionRite® upholstery foam. There's a CushionRite foam for all of your seating and upholstery needs. We're using CushionRite Premium in our video, but Standard is a great choice for occasional-use cushions that you don't use often.

Here's a closeup of the zipper closure on the bottom panel of our cushion cover.

Once the foam is cut to size, it's time to pattern your cushion cover shape using the foam piece. For this type of irregular cushion shape, it's necessary to use a patterning material to help with the cover design and assembly. We're using Dura-Skrim® Patterning Material to pattern our foam, but Sailrite® Patterning Material is also a great option.

Ready to make your own cushion cover for an oddly shaped space? You'll learn many valuable techniques in this video, including how to pattern from an irregular shape, how to install a zipper in a cushion bottom panel, how to get sharp corners on a cushion cover and more. Watch the video below to get started on your cushion project.

How did your irregularly shaped cushion turn out? Did you have fun making it? This DIY is part of our Cushion Masterclass video series. In this series, you’ll learn how to make a cushion seven different ways. There’s a technique for every use and style preference, so you can customize cushions for any space. Learn how to make a quick and easy platform cushion, a 30-minute cushion and more!

Our Cushion Masterclass series will teach you how to make all these popular cushion styles!

Video Chapters:

  • Intro — 0:00 min.
  • Cutting Foam to Size — 1:33 min.
  • Patterning From Foam — 5:28 min.
  • Cutting & Sewing Decorative Fabric — 16:59 min.
  • Bottom Plate Creation — 23:08 min.
  • Sewing Decorative Fabric to Bottom Plate — 32:41 min.
  • Inserting Foam in Cushion Cover — 40:26 min.
  • Materials & Tools List — 45:22 min.

Materials List:

  • CushionRite® Premium Antimicrobial Foam (Firm) — SKU: 124236
  • Dura-Skrim® Patterning Material 74" — SKU: 103134
  • 3M™ Super 77™ Spray Adhesive Low VOC 18 oz. — SKU: 636100
  • Décor & Upholstery Fabric from Sailrite — we used Sunbrella® Highlight Splendor - SKU: 57016-0003
  • Coats Extra Strong® Tex 70 Black Nylon Upholstery Thread — SKU: 104813 (Use Polyester for Outdoor Cushions)
  • Cushion Underlining Black 54" Fabric — SKU: 772100
  • Lenzip® #5 Black Continuous Coil Zipper Chain — SKU: 124596
  • Seamstick 1/4" Basting Tape for Canvas & Upholstery (36 yds.) — SKU: 122065
  • Lenzip® #5 Black Style A Single Locking Metal Zipper Pull (Coil Chain) — SKU: 124600
  • Cushion Wrap Silk Film 54" — SKU: 103933

Tools List:

  • Sailrite® Blade Foam Saw V2 with Carrying Case (110V) — SKU: 121244
  • Sailrite® Foam Shaper — SKU: 123583
  • Clear Acrylic Ruler 6" x 24" — SKU: 102400
  • Scribe-All® Black Marking Pencil for Vinyl — SKU: 121977
  • Sailrite® Tempered Cutting Glass — SKU: 121915
  • Sailrite® Edge Cordless Hotknife 18V Package — SKU: 122177
  • Small Fabric/Leather Clips (50 pack) — SKU: 123121
  • Magnetic Sewing Guide — SKU: 102983
  • Sailrite® Ultrafeed® LSZ Walking Foot Sewing Machine (110V) — SKU: 311602
  • Sailrite® Ultrafeed® Industrial Sewing Table — SKU: 120934
  • Scribe-All® Water Soluble White Marking Pencil — SKU: 120681
  • Gingher® 10" Bent Scissors — SKU: 120186
  • Basic Thread Snips — SKU: 123222
  • Marker, Straight Edge, Shop-Vac