Rib knit is the stretchiest everyday knit: vertical ribs that open up to 100% or more across the grain and spring back, which is why it is used for neckbands, cuffs and hem bands and for fitted tanks and tops. Sew it with a stretch needle in 75/11 or 80/12, polyester thread, a narrow zigzag or lightning stitch (or a 4-thread overlock), a 1 cm (3/8 in) seam allowance and a light hand: never pull it through the machine. Cut bands at 75–90% of the edge they will finish, press on the wool setting with steam while lifting the iron rather than sliding it, and hem with a twin needle.
Quick reference: how to sew rib knit
| Setting | Rib knit (1×1 and 2×2 ribbing) |
|---|---|
| Needle | Stretch 75/11 for fine rib; 80/12 or 90/14 for heavy cotton rib |
| Thread | All-purpose polyester; wooly nylon in the serger loopers |
| Stitch | Narrow zigzag 0.5 × 2.5 mm or lightning stitch; 4-thread overlock |
| Presser foot | Walking foot, or standard foot with the pressure reduced |
| Pre-wash | Yes, warm wash and tumble dry: 3–6% shrinkage, mostly lengthwise |
| Pressing | Wool setting with steam, lift and lower, never drag; finger-press bands |
| Seam finish | None needed; serged for a tidy inside |
| Band length | 75–90% of the finished edge, depending on the opening and the rib |
| Hems | Twin needle 4 mm, zigzag or coverstitch; a plain hem stretches, so stabilize it |
What is rib knit and how is it different from jersey?
Rib knit is knitted with alternating columns of knit and purl stitches, which pull together into vertical ribs. The ribs let the fabric open wide across the grain and close back up, so the crosswise stretch is 50–100% or more with excellent recovery, far more than jersey. Rib looks the same on both sides, lies flat at the edges and does not curl like jersey.
The names describe the ribbing pattern: 1×1 rib alternates one knit column with one purl and makes a fine, smooth rib; 2×2 rib (two and two) is the deep ridged ribbing of a classic tank top and stretches further. Rib knit is sold by the meter at 150–280 GSM (4.5–8 oz/yd²), usually cotton with 5% elastane, and also as tubular ribbing in narrower widths meant for bands. Cotton rib without elastane stretches as much but recovers slowly, which shows as a neckband that gapes after a few wears; for bands, choose the blend.
How much shorter should a rib knit band be?
Shorter than the edge it finishes, so that it draws the opening in and lies flat. The ratio depends on the opening and on the stretch of your rib:
| Band | Length as a share of the edge | Example on a 50 cm (19 3/4 in) edge |
|---|---|---|
| Crew neckband | 80–85% | 40–42.5 cm (15 3/4–16 3/4 in) |
| Wide or scoop neckband | 85–90% | 42.5–45 cm (16 3/4–17 3/4 in) |
| Sleeve cuff | 75–85% | 37.5–42.5 cm (14 3/4–16 3/4 in) |
| Sweatshirt hem band | 85–90% | 42.5–45 cm (16 3/4–17 3/4 in) |
| Tank armhole band | 85–90% | 42.5–45 cm (16 3/4–17 3/4 in) |
Measure the finished edge on the pattern, without seam allowances, multiply, then add the seam allowance to join the band into a loop. A very stretchy 2×2 rib takes the lower figure; a firm 1×1 cotton rib the upper one. The neckband tutorial shows the quartering method that spreads the difference evenly.
How do you cut rib knit?
Rib has a strong grain and an even stronger urge to stretch, so cut it as flat as it lies:
- Ribs run lengthwise, along the grain. For bands, the length of the band runs across the ribs, so the stretch goes around the neck or wrist; for a tank or top, the grainline follows the ribs.
- Let it rest after pre-washing, flat on the table for an hour, before you measure or cut.
- Cut in a single layer with weights and a rotary cutter. Rib shifts in a fold, and a band that is 1 cm (3/8 in) off in width shows.
- Cut bands slightly long and trim to the ratio after checking the stretch of your actual fabric: a 10 cm (4 in) strip stretched between your hands tells you whether you have a 75% or an 85% rib.
- Mark with chalk or clips, not pins; the loose knit swallows a pin and the hole stays.
How do you sew rib knit without stretching it?
The seam itself is the same as on any knit, described in sewing knit fabrics; rib adds the risk of stretching, because it gives so easily.
- Stretch needle, 75/11 or 80/12. Its tip and scarf are made for elastane blends and stop the skipped stitches that a universal needle causes in rib.
- Stretch stitch. A narrow zigzag of 0.5 mm wide and 2.5 mm long on the machine, or a 4-thread overlock, which trims and seams the 1 cm (3/8 in) allowance in one pass.
- Reduce the pressure or fit a walking foot. Too much foot pressure pushes the top layer ahead and stretches the seam into a wave.
- Hands flat, no pulling. Guide the fabric; the feed dogs move it. If the seam still waves, sew it over a strip of tissue paper and tear the paper away.
- Stabilize shoulders and straps with clear elastic or fusible knit tape; a rib tank hangs from its shoulders and will grow there otherwise.
- Sew bands into a loop first, then quarter the band and the edge, match the marks and stretch the band only to fit between them, with the band on top.
For fitted tops and tanks, rib knit is cut with negative ease: the pattern is smaller than the body, typically 5–10% at the bust for a 2×2 rib, and the fabric stretches to fit. A rib with 100% stretch can take more negative ease than one with 50%. Sewly's T-shirt and tank pattern uses a 1 cm seam allowance on knits by default, so the pieces are ready for a serger.
How do you press rib knit?
Lightly. Set the iron to wool with steam, hover over the seam, then set the iron down for a second and lift it. Sliding the iron along a rib seam stretches it, and pressing hard flattens the ribs so the band loses its spring. Press band seams toward the body, then from the right side with the band stretched gently flat under a press cloth.
How do you hem rib knit?
Bands are the natural finish, and most rib garments have them. A plain hem is possible on a rib tank or top: fold up 2 cm (3/4 in), fuse a strip of knit tape into the fold, and stitch from the right side with a 4 mm stretch twin needle at a 3.5 mm stitch length, or a narrow zigzag. The twin needle gives two parallel rows with a zigzag underneath that stretches. On a deep 2×2 rib, test on a scrap: a twin needle can tunnel between the ribs, and a wider 6 mm twin needle or a coverstitch sits better. Test all three on a scrap before you commit.
What should you sew with rib knit?
- A fitted T-shirt or tank in 2×2 cotton-elastane rib, with self-fabric bands at the neck and armholes.
- Bands for a sweatshirt: neckband, cuffs and hem band in 1×1 rib matched to the French terry or fleece of the body.
- Cuffs and a waistband for joggers, where ribbing holds the leg at the ankle.