The Three Basic Weave Structures: Plain, Twill and Satin

Almost every woven fabric you own is one of three structures, or a variation on one. Knowing them helps you read cloth as well as weave it.

A few words first

Warp and weft are the two basic components of woven cloth: the warp is the set of lengthwise threads held in tension on the loom, and the weft is drawn through them crosswise. Single warp threads are called ends and single passes of weft are called picks. How closely the ends are spaced is the sett, and the reed, a comb-like frame with many slots, spaces the warp and pushes each pick into place. The finished side edges are the selvedges, self-finished so they do not unravel.

Plain weave

Plain weave is the simplest structure: each weft thread crosses the warp by going over one, under the next, and so on, and the next pick does the opposite. It needs only two sheds, which is why every loom can weave it. Plain weave makes a firm, stable cloth with the maximum number of interlacings, and it shows colour changes clearly, which is why it is the home of stripes, checks and plaids.

When warp and weft are of similar thickness and spacing, plain weave is balanced and both sets of threads show equally. Spread the warp out and pack the weft in and you get a weft-faced cloth, like many tapestries and rugs, where the warp is hidden. Do the opposite and the cloth becomes warp-faced, as in many woven bands.

Twill

Twill is made by passing the weft over one or more warp threads and then under two or more, with a step, or offset, between rows. That step is what creates the diagonal lines you see on denim and many suiting fabrics. Because each thread floats over more than one other before interlacing, twill has fewer interlacings than plain weave, so it can be packed more densely and generally drapes well.

Twills are named by their float lengths. A 2/2 twill has the weft going over two and under two; a 3/1 twill over three and under one. On a four-shaft loom, a straight threading and a simple lifting sequence give a straight twill, and reversing the direction of either the threading or the lifting gives points and diamonds. This is where shaft looms start to pay for themselves.

Satin

Satin is the third fundamental structure. Long floats are arranged so that the interlacing points are scattered rather than lined up in a diagonal, which gives a smooth, glossy face and a dull back. The trade-off for that lustre is durability: long floats can snag. True satin needs more shafts than a beginner's loom usually has, and is less common in handweaving than plain weave and twill.

How to tell them apart in a shop

1. Look closely at the surface with good light, or with a magnifier.
2. If every thread goes over one and under one, it is plain weave.
3. If you can see clear diagonal lines, it is a twill. Check which way they run.
4. If one face is smooth and shiny with almost no visible interlacing, and the back is matte, it is probably a satin.

All three structures can be written down precisely. The note on reading a weaving draft shows how.

Revised 2026-11-09 · Margit Halloway