Canvas is one of the oldest and most hard-working fabrics in the textile trade. It shelters people in tents, protects goods under tarpaulins and truck covers, carries books and tools in bags, forms the uppers of everyday shoes and holds the paint of artists. Pakistan has a long tradition of weaving heavy cotton fabrics, backed by locally grown cotton and a deep spinning base, and canvas remains one of the country's most recognised textile products.
At Soltex we supply cotton canvas and duck canvas fabric for manufacturers who need a dependable base cloth. This page explains the main types of canvas, how weight is measured and converted, what greige, dyed and finished canvas mean in practice, which finishes are available, and how to match a canvas specification to an end use. If you already know your requirement, send us your specification for a quotation.
What Is Canvas Fabric?
Canvas is a heavy, closely woven fabric, traditionally made from cotton and usually woven in a plain weave. Its strength comes from coarse, strong yarns packed tightly together. Compared with ordinary shirting or sheeting, canvas uses much thicker yarns and a higher cover factor, which means there is very little open space between the threads. That tight structure gives canvas its stiffness, abrasion resistance, tear strength and natural resistance to wind and light rain.
Most cotton canvas is woven from carded or open-end cotton yarn in coarse counts, often plied in the warp and sometimes in the weft as well. Plying two or more single yarns together evens out weak spots, raises strength and gives a rounder yarn that packs more uniformly in the cloth. The choice between single and plied yarns, and the number of ends and picks per inch, determine how heavy, firm and durable the canvas will be. Our yarn and threads range covers the coarse cotton counts used for this kind of weaving.
Types of Canvas We Supply
Plain cotton canvas
Plain cotton canvas is the general-purpose form, woven one-over-one-under from cotton yarns. It is used for tents, covers, bags, aprons and many craft and industrial items. Weight can range from light, flexible canvas suitable for tote bags and printing to very heavy cloth for covers and shelters. Because it is all cotton, it accepts reactive and vat dyes well, can be bleached to a clean white and takes water-repellent finishes readily.
Duck canvas fabric
Duck canvas is a tightly woven canvas, typically smoother and more compact than standard canvas. The name is thought to come from the Dutch word doek, meaning cloth. In the trade, duck is often described in three ways:
- Single fill duck uses single (unplied) yarns in the weft, with the warp often plied or paired. It is a lighter, economical duck widely used for bags, aprons, covers and printing.
- Double fill duck inserts two weft yarns together in each pick, giving a heavier and firmer cloth for workwear, tool bags and covers.
- Army duck or plied yarn duck uses plied yarns in both warp and weft, giving a smooth, balanced and very strong cloth for tents, military goods and premium bags.
Numbered duck
Numbered duck is a traditional grading system for heavy cotton duck, mainly used in North American trade. The lower the number, the heavier the cloth. Under the customary rule, subtracting the duck number from 19 gives the weight in ounces of a piece 22 inches wide and one yard long. That figure is then converted to a square-yard basis. Because the system was defined for a nominal construction, real fabrics vary, so we always confirm numbered duck orders in GSM and construction. The table later on this page gives approximate equivalents.
Poly-cotton canvas
Poly-cotton canvas blends polyester with cotton, either as blended yarn or by using polyester in one direction and cotton in the other. Polyester adds tensile and tear strength, reduces shrinkage and helps the fabric hold its shape when wet. A poly-cotton canvas can therefore be lighter than an all-cotton canvas for a similar strength. It is popular for modern tents, awnings, bags and workwear. Cotton-rich blends keep more breathability and a softer hand, while polyester-rich blends are firmer and more stable.
Canvas Weight: GSM and oz/yd² Explained
Canvas weight is the single most quoted specification, but it is also the one most often misunderstood. Buyers in Pakistan, Europe and much of Asia use grams per square metre (GSM). Buyers in the United States and some legacy specifications use ounces per square yard (oz/yd²), and some traders quote ounces per linear yard at a stated width. Mixing these units is a common source of disputes.
Conversion: 1 oz/yd² = 33.906 g/m². To convert GSM to oz/yd², divide by 33.906. A 10 oz canvas is about 339 GSM, a 12 oz canvas about 407 GSM and an 18 oz canvas about 610 GSM.
If a weight is quoted per linear yard, you also need the width. For example, a fabric weighing 15 oz per linear yard at 60 inches wide works out to 15 × 36 ÷ 60 = 9 oz/yd², or about 305 GSM. When you send us an enquiry, tell us which basis your buyer uses and we will confirm the specification on the same basis.
Canvas Specifications
The table below shows typical weight bands, approximate conversions and common uses. These are guidance ranges, not fixed grades. We weave or source to the exact construction you specify.
| Weight band | Approx. oz/yd² | Typical construction notes | Common uses |
|---|---|---|---|
| 200–280 GSM | 6–8 oz | Single yarns or light plied warp, plain weave | Tote and promotional bags, aprons, printing, linings |
| 280–400 GSM | 8–12 oz | Plied warp, single or double fill | Bags, shoe uppers, painting canvas, light tents |
| 400–550 GSM | 12–16 oz | Plied warp and weft, high cover | Tents, workwear, tool bags, covers, awnings |
| 550–700 GSM | 16–21 oz | Heavy plied yarns, very compact weave | Tarpaulins, truck covers, frame tents, heavy covers |
| 700–900 GSM | 21–27 oz | Very coarse plied yarns, often double fill | Industrial covers, heavy tarpaulins, belting and specialist uses |
Approximate numbered duck equivalents, based on the customary rule described above, are as follows. Treat them as a starting point for discussion, not a guarantee of construction.
| Duck number | Approx. oz/yd² | Approx. GSM |
|---|---|---|
| #4 | 24.5 | 830 |
| #6 | 21.3 | 720 |
| #8 | 18.0 | 610 |
| #10 | 14.7 | 500 |
| #12 | 11.5 | 390 |
Beyond weight, a full canvas specification should state fibre content, warp and weft counts and ply, ends and picks per inch, weave, finished width, shade, finish, and acceptable tolerances for GSM and width. Many buyers also specify tensile and tear strength, shrinkage, and for finished canvas, water resistance or flame performance with a named test method.
Greige, Dyed and Finished Canvas
Greige canvas
Greige (also written grey or gray) canvas is fabric as it comes off the loom, before any wet processing. It is natural off-white to light brown, may contain size from weaving and has a firmer, slightly rough hand. Greige canvas suits customers who have their own dyeing or coating partner, and buyers who want the natural look of unbleached cotton for bags, upholstery or art canvas. It is also the most economical way to buy canvas in bulk.
Bleached and dyed canvas
Bleached canvas is scoured and whitened to give a clean base for printing or pale shades. Dyed canvas is coloured in the piece, most commonly with reactive or vat dyes for cotton. Heavy canvas is harder to dye evenly than light fabric, because dye must penetrate thick, tightly packed yarns, so shade consistency between lots and from edge to centre needs careful control. We agree shade standards and tolerances before processing and keep reference swatches against each lot.
Finished canvas
Finished canvas has been treated to add a specific performance property, such as water repellency or flame retardancy. Finishing changes weight, stiffness and hand, so the specification for finished canvas should state the weight before and after finishing.
Canvas Finishes
Finishing is carried out by specialist processors with the equipment and chemistry for each treatment. Soltex coordinates this work so you receive finished canvas from one supplier. Typical finishes include:
- Water-repellent finish. Causes water to bead and run off the surface while keeping the fabric breathable. Cotton fibres also swell when wet, tightening the weave, which is why well-constructed cotton canvas performs well in tents. Water repellency is different from waterproof coating; if you need a fully waterproof fabric, a PVC, PU or similar coating is required.
- Rot-proof (anti-rot) finish. Cotton is a natural fibre and can be attacked by mildew and rot-causing organisms if stored or used damp. Rot-proof treatments help protect canvas for tents, tarpaulins and covers that will be exposed to moisture.
- Fire-retardant finish. Reduces flame spread for tents, marquees, stage and event uses. Requirements differ by country and application, so the finish must be matched to the test standard your buyer names.
- Softening, stiffening and calendering. Adjust hand feel and surface. Calendering presses the fabric flat and smooth, which helps printing and painting canvas.
- Coating and lamination. PVC or other coatings for fully waterproof tarpaulins and covers can be arranged through coating houses.
Finishes do not last forever. Repeated washing, abrasion, sunlight and weathering reduce performance over time. Re-proofing products exist for tents and covers in service. We recommend that you test a finished sample in your own conditions before confirming a bulk order.
Uses of Cotton Canvas and Duck Fabric
Tent canvas
Cotton and poly-cotton tent canvas breathe, which reduces condensation inside the tent compared with many fully synthetic fabrics. Cotton also swells slightly when wet, tightening the weave against rain. Tent canvas is usually medium to heavy weight with a water-repellent and often rot-proof finish, and fire-retardant finishing is common for event tents and marquees. Pakistan has a long history of supplying canvas for tents, both for the local market and for export.
Tarpaulin canvas and truck covers
Tarpaulin canvas is typically heavy, often 550 GSM and above, with water-repellent and rot-proof finishes. It is used to cover goods, machinery, trucks and storage stacks. Truck covers need high tear strength, good seam holding and resistance to wind flap and abrasion against loads. Heavier, more compact constructions and plied yarns are preferred. For fully waterproof covers, coated fabrics are used instead of, or on top of, cotton canvas.
Bags, luggage and accessories
Canvas makes school bags, backpacks, tool bags, laptop bags and tote bags. Lighter grades suit printed promotional bags, while heavier duck suits rugged work and travel bags. Bag makers often want a firm hand, good printability and colour fastness, and may specify a back coating for stiffness or water resistance.
Shoe canvas
Canvas shoe uppers require a smooth, even surface, consistent weight and good bonding to rubber soles. Shoe canvas is often dyed in fashion shades and must have good rub and wash fastness. Dimensional stability matters because uppers are cut from patterns and lasted under tension.
Painting canvas
Artist canvas is usually cotton duck or plain canvas with a very even surface and few knots or slubs. It is stretched on frames and primed with gesso or acrylic primer. Many art suppliers buy greige canvas and prime it themselves; others buy primed rolls. Surface uniformity and freedom from faults are more important here than in most industrial uses.
Aprons, workwear and home goods
Canvas aprons, work jackets, upholstery, cushion covers, laundry baskets and storage items all rely on canvas for durability. These uses often call for medium weights, softer finishes and dyed shades. For lighter woven fabrics such as drill and twill, see our weaving and woven fabrics page.
How to Specify Canvas for Your Order
A clear specification saves time and prevents disputes. When you contact us, include as much of the following as you can:
- End use. Tell us what the canvas will become. This helps us suggest a construction if you do not have one.
- Fibre content. 100% cotton or a poly-cotton ratio.
- Weight. GSM, or oz/yd² with the basis stated, plus tolerance.
- Construction. Warp and weft counts and ply, ends and picks per inch, weave and fill type.
- Width. Finished width, and whether it includes selvedge.
- State and finish. Greige, bleached, dyed or finished, with any required test methods.
- Packing. Roll length, core, wrapping and labelling.
- Quantity and destination. For freight and lead time planning.
If you have an existing fabric, send a swatch. We analyse construction, counts and weight and propose a matching canvas, then send a sample for your approval before bulk production.
Quality Checks on Canvas
Canvas faults that look small on a roll can become expensive once the fabric is cut and stitched. Our checks focus on the properties that matter to fabricators: GSM against the agreed tolerance, finished width, ends and picks per inch, visible weaving faults such as broken ends, missing picks, slubs, knots and oil stains, and shade against the approved standard for dyed goods. Results are recorded by lot so a repeat order can be matched to the previous delivery. Where you need laboratory tests for tensile strength, tear strength, water repellency or flame performance, we can arrange testing to the method you specify.
Canvas is also only as good as the thread used to sew it. Heavy bonded and spun polyester threads for tents, tarpaulins and bags are available from our thread range, so you can source fabric and sewing thread together.
Canvas Fabric FAQs
What is the difference between canvas and duck fabric?
Both are tightly woven plain-weave cotton fabrics. In the trade, duck usually refers to a smoother, more closely woven canvas, often with plied warp yarns, and is sold by weight or by a duck number. Canvas is the broader term. Always confirm GSM and construction rather than relying on the name alone.
How do I convert oz per square yard to GSM?
Multiply ounces per square yard by 33.906. For example, 10 oz/yd² is about 339 GSM, 12 oz/yd² is about 407 GSM and 18 oz/yd² is about 610 GSM. Check whether your buyer quotes weight per square yard or per linear yard at a given width, because the two are not the same.
Which GSM should I choose for tent canvas?
Lighter family and festival tents often use canvas around 280 to 400 GSM, while heavier frame tents, shelters and marquees commonly use 400 to 600 GSM or more. The right choice depends on frame design, climate, finish and how long the tent must last, so we recommend testing a sample with your chosen finish.
Can you supply waterproof or fire-retardant canvas?
Yes. We arrange water-repellent, rot-proof and fire-retardant finishing through specialist processors. Performance depends on the base fabric, the chemistry and the test method your buyer requires, so we agree the finish and the test standard in writing before processing.
Do you supply poly-cotton canvas as well as 100% cotton?
Yes. Poly-cotton canvas blends polyester with cotton to improve strength, reduce shrinkage and lower weight for the same performance. Cotton-rich blends keep much of the breathability and hand feel of cotton canvas, while polyester-rich blends are stiffer and more dimensionally stable.
Can I order greige canvas and finish it myself?
Yes. Many customers buy greige canvas straight off the loom and send it to their own dyeing or coating house. We can also supply bleached, dyed or finished canvas if you prefer a single source.
Looking for a cotton canvas supplier?
Tell us the GSM, width, finish and end use and we will quote for greige, dyed or finished canvas.