What Is Canvas?

How is canvas made?

Canvas is made by plain-weaving thick, usually plied yarns into a dense, stout cloth. Plain weave is the simplest interlacing: each crosswise thread passes over one lengthwise thread and under the next.

The fibre has changed over time. The name points to hemp, and hemp and flax have long been used for sailcloth. Once the power loom arrived, canvas was woven from flax, hemp, tow (the short, coarse flax fibre), jute, cotton and blends of them. A canvas jacket or bag can therefore be cotton, linen, hemp or a blend; the content label says which.

Two construction choices make canvas heavy and strong:

• Plied yarns. Canvas yarns, usually cotton, flax or jute, are typically multi-ply: two or more strands twisted together. Plying tends to give a yarn of even thickness.
• Doubled warp. Flax canvas is essentially woven with a double warp, which suits it to pressure and rough use. Lighter artists' canvas uses a single warp.

Is tailoring canvas the same thing?

No. Tailors also say "canvas" for the stiff interlining built into the front of a jacket. That is a hidden support layer, covered under interfacing and tailoring, not the outer cloth described here.

What are the properties of canvas?

Canvas is heavy, firm and hard-wearing, with an even surface. Those traits explain where it has always been used: sails, tents, awnings and bags, and in clothing and footwear where abrasion matters.

• Strength. Plied yarns and a close plain weave make a stout cloth; doubled-warp canvas is built to take rough handling.
• Even thickness. Plying tends to even out the yarn's thickness, so good canvas looks and feels uniform.
• Stiffness and structure. A heavy canvas holds its shape, which is why it suits tote bags, work trousers and jackets more than drapey dresses.
• Footwear use. Britannica lists shoes for games, running and yachting among canvas's uses.

Canvas is not the same weave as denim or other twill cloths. A twill steps its interlacing to form diagonal ridges; canvas has none.

Canvas, duck and artists' canvas

The names overlap. The Museum of Fine Arts, Boston's CAMEO materials database lists "duck" as a synonym for canvas, and certain classes of cloth are called sailcloth or canvas interchangeably. Artists' canvas is a lighter, single-warp cloth, traditionally of bleached or cream flax, treated after weaving to take paint.

How is canvas graded or measured?

Canvas is described by weight, and in the United States heavy cotton canvas can be graded under a numbered duck system based on weight per linear yard.

The numbering was already established in the trade by 1924, when the US Bureau of Standards worked with the Cotton Duck Association on a standard specification to replace the many competing ones. Under it:

• Weight is measured per linear yard of cloth 22 inches wide, in ounces.
• The number is 19 minus the weight in ounces, so the lower the number, the heavier the cloth: No. 9 duck weighs 10 ounces per linear yard.
• Cloth of 19 ounces or more per linear yard takes a "/0" grade instead, and here the order runs the other way: 19 ounces is 1/0, 20 ounces is 2/0.
• Numbered duck spans about 7 to 30 ounces per linear yard, equal to about 11 to 49 ounces per square yard.

The two ways of quoting weight are not interchangeable. By our conversion, 11 to 49 ounces per square yard is roughly 370 to 1,660 g/m². When a maker quotes "oz", ask whether it is per square yard or per linear yard of a given width.

How does canvas appear on a clothing label?

Canvas never appears as a fibre on a care or content label, because it names a weave, not a fibre. The label lists what the canvas is woven from.

• In the US, fibres are listed by generic name with their percentage by weight, in descending order of predominance. Fibres under 5% may be grouped as "other fiber" (wool excepted). A 3% tolerance applies to stated percentages, but not when the label says the product is a single fibre.
• In the EU, and in the UK's retained version of the same regulation, the listed fibre names include "cotton", "flax (or linen)", "true hemp" and "jute".

So "100% cotton" on a canvas jacket is a single-fibre claim, and the 3% tolerance does not apply to it. A content line such as "65% polyester, 35% cotton" means a blended cloth woven in a canvas structure; it is still canvas, but it will handle and age differently from all-cotton canvas.

How do you tell good canvas from poor canvas?

Good canvas is heavy for its use, woven from even, plied yarns, and honestly labelled. Four checks you can do in a shop:

1. Read the weight. Ask for the figure and the unit. A bag or work jacket sold as "canvas" with no weight given tells you little; compare like with like (per square yard or g/m²).
2. Untwist a thread. Find a loose end in a seam allowance and roll it between finger and thumb. Two or more strands twisted together confirm plied yarn, the basis of canvas's even thickness.
3. Look along the cloth. Plied yarns should give an even surface. Thick-and-thin yarns or a visibly uneven weave are a warning sign, because plying is what tends to give canvas yarn its even thickness.
4. Read the content line. Check the fibre percentages and remember that a single-fibre claim carries no tolerance.

Red flags: a "canvas" garment that feels like ordinary shirting, a weight given without saying per what, and a content label that lists no fibre percentages at all.

How do you care for canvas?

Care canvas according to its fibre and finish, starting with the care label. A cotton canvas tote and a linen canvas jacket can need different handling.

• Brush off dried dirt before it is worked into the weave.
• Spot-clean small marks rather than washing the whole piece.
• Let canvas dry fully before storing.
• Waxed canvas is a coated cloth with its own routine; do not treat it like plain canvas.

Is canvas sustainable?

Canvas is neither sustainable nor unsustainable as a category; its impact depends on the fibre, how that fibre was grown and processed, and how long the item is used. The weave itself is a structure, not a material.

The fibre is the first thing to check. Cotton comes from the bolls of the cotton plant, linen from the stem (bast) of flax, true hemp from the bast of Cannabis sativa, and jute, the fibre of burlap, from the bast of Corchorus plants. Each has a different farming and processing profile, so read the content line before accepting a general green claim. Canvas made for hard use is also built to last, which matters most if the item is actually kept and worn.