Sewing with French terry: sweatshirts and joggers

French terry is a soft, medium-weight cotton knit with a smooth jersey face and loops on the back, and it is one of the easiest knits to sew: it is stable, barely curls and stretches moderately (20–50% across the grain). Use a stretch or ballpoint needle in 80/12 or 90/14, polyester thread, a narrow zigzag or lightning stitch of 0.5 × 2.5 mm (or a 4-thread overlock), a walking foot if you have one, pre-wash because cotton French terry shrinks 3–5% in length, and press on the wool setting with steam without dragging the iron. Hems take a twin needle or coverstitch, and cuffs, neckbands and waistbands come from matching rib knit.

Quick reference: how to sew French terry

What is French terry and how is it different from sweatshirt fleece?

French terry is a weft knit with a smooth, flat face of fine vertical ribs and a back covered in small loops of yarn, like a towel that has not been brushed. It weighs 200–300 GSM (6–9 oz/yd²); the lighter end is a heavy T-shirt and the heavier end is a light sweatshirt. The loops hold a little air and wick moisture, which is why joggers and sweatshirts in French terry feel cooler than fleece.

Sweatshirt fleece is the same construction with the loops brushed into a fuzzy nap, warmer and thicker. Jersey is lighter with no loops; interlock is smooth on both sides. The four behave differently enough that the pattern should say which it expects.

Most French terry is cotton, often with 5% elastane for recovery. Pure cotton French terry stretches about 20–30% across the grain and recovers slowly; with elastane it stretches 40–50% and springs back. Check the stretch before you choose a pattern: the stretch percentage test takes a minute. A sweatshirt with 10–15 cm (4–6 in) of ease works in either; fitted joggers want the elastane version.

Should you pre-wash French terry?

Yes. Cotton knits shrink more along the length than across, often 3–5% and sometimes more on a loosely knitted terry, and a sweatshirt cut from unwashed fabric comes out of its first wash 3 cm (1 1/4 in) shorter. Wash warm and tumble dry on medium, then let the fabric rest flat before cutting; a knit taken straight from the dryer to the cutting table is still stretched. The loops shed lint in the first wash, which is normal.

How do you cut French terry?

French terry is far easier to cut than jersey. It is thick enough to lie flat, and the edges barely curl.

• Find the grain. The fine ribs on the face run along the grain; the loops on the back run in rows across it. Fold along a rib, not along the cut edge, which is rarely straight.
• Put the greatest stretch around the body. On French terry that is across the grain, so the grainline on the pattern runs along the ribs.
• Fold or single layer. A folded layout works for sweatshirt bodies and sleeves. Cut pockets, bands and cuffs in a single layer so they come out square.
• Use weights and a rotary cutter. Pins lift the loops; weights and a 45 mm blade give clean edges.
• Cut the bands from rib knit at 80–90% of the edge they will join, as explained in the rib knit post. French terry itself can make a band on a loose sweatshirt, but it recovers less than ribbing.

How do you sew French terry on a regular sewing machine?

A serger is quick but not required; a home machine with a zigzag sews French terry well. The method in sewing knit fabrics applies, with a few points specific to terry:

1. Fit a stretch or ballpoint needle. The rounded tip slides between the loops instead of piercing the yarn; a universal needle in French terry causes skipped stitches.
2. Set a stretch stitch. A narrow zigzag of 0.5 mm wide and 2.5 mm long stretches with the seam without looking like a zigzag; the lightning stitch does the same. Sew a sample and pull it: if the thread snaps, widen the zigzag.
3. Lower the presser foot pressure or fit a walking foot. The loops on the back grip the feed dogs and the top layer can lag, which stretches the seam and leaves the two layers uneven at the end. A walking foot moves them together.
4. Do not pull. Guide the fabric with your hands flat in front of and behind the foot, and let the machine feed. A stretched seam waves after pressing.
5. Use a 1 cm (3/8 in) seam allowance, which is what Sewly's knit patterns draft by default and what a 4-thread serger trims to. Knits do not fray, so the raw edges can stay as they are.
6. Stabilize the shoulders with 6 mm (1/4 in) clear elastic or a strip of fusible knit tape sewn into the seam, so the sweatshirt does not stretch across the back from hanging.
7. Attach bands stretched to fit. Quarter the band and the edge, match the pins, and stretch the band, never the body, to fit between them as you sew.

Pockets on joggers and a sweatshirt kangaroo pocket are topstitched on with a 3 mm straight stitch; a straight stitch is fine wherever the seam will not be stretched in wear.

How do you press French terry?

On the wool setting with steam, from the smooth side, lifting and setting the iron down rather than sliding it. Press seams to one side and band seams toward the body. Too hot an iron on an elastane blend leaves a shine and can flatten the loops permanently; test on a scrap.

How do you hem French terry?

The best hem on a sweatshirt is a rib band; on joggers it is a cuff. Where you want a plain hem, on a cropped sweatshirt or shorts, fold up 2.5 cm (1 in), press, and stitch from the right side with a stretch twin needle (4 mm) at a 3.5 mm stitch length, or with a coverstitch machine. A strip of fusible knit tape in the fold stops the hem from tunneling. The knit hem comparison shows the three finishes and how each looks.

What should you sew with French terry?

• A crew-neck sweatshirt or hoodie in 250–300 GSM French terry with rib bands at the neck, cuffs and hem.
• Joggers in 240–280 GSM cotton-elastane French terry, with an elastic waist, ribbed cuffs and in-seam pockets.
• Pull-on shorts or a heavy T-shirt in a light 200 GSM French terry for lounging.