When shopping for fabric online, can you imagine how the fabric will look on your body or feel when you sew it? Or is it hard to imagine what you will receive when your online fabric order arrives at your door?

There are two ways to really get to know fabric, and the first way is technical. You can research the properties of individual fibers, such as cotton, rayon, silk, polyester, or wool. This gives you an idea of ​​how the fibers absorb dye, wick away moisture, or keep you warm or cool. You can then explore how those fibers are knitted or woven to create a particular fabric. For example, the fibers may be combined with nylon or spandex to provide flexibility, or woven in a way like twill or velvet to create texture on the surface. You can learn this information online, in books (see a suggested list below), or through experience sewing.

But the second way to really get to know fabric is through your senses. You see how the fabric drapes over your body, how heavy it feels when you hold it, and how it moves when you walk. Unfortunately, you miss out on almost the entire sensory experience when shopping for fabric online.

So if you can’t touch your fabric before you buy it, a quick vocabulary lesson can help bring fabric descriptions to life. Becoming familiar with the sensory qualities of the fabric—especially its weight and drape—will help you know how it will behave when you unbox it, sew it, and wear it.

Know the Terms: Weight and Casting

Online fabric stores have the difficult task of translating the behavior of a fabric into a written description. Your job when shopping is to learn how to interpret fabric descriptions. When reading a fabric description, pay attention to the fiber content and then look at the adjectives stores use to describe its weight and drape. The more you do this, the faster you will learn the language of textiles.

In short, the weight of the fabric is how light or heavy it feels when you pick it up, and the drape of the fabric is how it hangs on your body. Let's take a closer look at each of these terms now.

Weight

Why?

The weight of a fabric is how light or heavy it is. Fabrics are often described as light, medium weight, or heavy, but each fabric also has a specific, numerical weight.

Depending on where you shop for fabric, the metric unit of weight used is usually grams per square metre (g/m²).

So what do these numbers mean when shopping for fabric for a particular sewing project? Here are some general examples of how you might think about weight for your sewing project:

• Lightweight fabrics can be thinner, more breathable, more flowing and less opaque. These fabrics are those up to approximately 237 g/m².

• Heavyweight fabrics can be thicker, more durable, more opaque and more structured. These fabrics are those over 475 g/m².

• Midweight fabrics fall between these two extremes and weigh around 373-475 g/m².

It is important to remember that the fabric weight in g/m² only reflects the weight per square metre. This does not include additional information such as the weave density, other fibre content, drape quality or the stretch of the fabric. Therefore, although the specific weight of the fabric may be listed, you will need to rely on the description to find out more information.

Example: Denim

Denim is a great example to explore weight because online fabric stores usually provide very detailed information and ready-to-wear jeans usually state the weight of the denim. You can find lightweight, midweight and heavyweight denim, ranging from around 170 grams per square metre to 1,085 grams per square metre.

Denim also requires you to consider how you want your garment to feel on your body. For example, heavyweight denim can withstand more wear and tear than lightweight denim, but it can also feel more restrictive on your body until it softens.

The denim sample on the left is listed as heavy. It weighs 438 g/m² (approximately 12.9 oz) and is described in the online description as tough, durable, and heavy. Ideal for sturdy jeans, aprons, and overalls. Notice how this denim sample holds its shape even when hung. The fabric is so heavy that it stays stiff and doesn't show any flaking.

The denim in the middle is listed as a medium weight. It is 329 g/m² (approximately 7 oz) and is described as having a textured, opaque and drapeable drape. Ideal for jeans, jackets, skirts and bags. Note that it forms a large fold when hung, meaning it has a slightly more drape than the heavyweight denim.

The final denim is listed as lightweight. It weighs 203 g/m² (approximately 6 oz) and is described as soft, thin, and breathable. It’s ideal for relaxed-fit trousers and shirts. Note that this sample folds more when hung—it has more drape than the other two.

Guide to Choosing the Right Fabric Weight

If a fabric has g/m² (grams per square metre), stores will usually state this in the product description or in a sidebar on the product page. Otherwise, it may simply be described as "light", "medium" or "heavy".

When looking at fabric weight, ask yourself these questions:

• Should my fabric be sheer or opaque?

• Would a lightweight fabric make sewing difficult for this project?

• Does the weight of the fabric create thickness in the seams?

• Is the fabric sturdy enough to withstand the stress from the seams?

• How do I want the fabric to feel on my body? (Think breathability and ease of movement.)

Weight is just one of the factors you need to consider when choosing a fabric, and it should always be considered along with drape.

Casting

Why?

Drape describes how fabric hangs, falls, and curls on the body. It’s often confused with weight, which is understandable because the two are strongly related. In other words, heavy fabrics tend to have less drape, while lightweight fabrics tend to have more drape.

However, this is not always true and the relationship is not one-to-one. For example, there are fabrics that are heavy but fluid, such as heavy wool crepe. On the other hand, there are fabrics that are light but stiff, such as organza. Even fabrics of the same weight can have large differences in drape. So when choosing a fabric, remember to consider weight and drape together.

Example: Two Different Flannels

Cotton is a great example to explore drape. There are so many types of cotton fabric and while they are all 100% cotton, how do you know which one to choose? See what the online store has to say about drape.

Both examples are 100% cotton flannel. The buffalo flannel on the left weighs 151gsm and is described as having a flexible drape. The Italian flannel on the right weighs 105gsm and is described as “exceptionally soft” and has a slight, wavy drape. Although they are similar in weight, they have a big difference in drape.

How does draping affect the fit of a garment?

The concept of drape is a bit more ambiguous than weight, as it is not expressed in units of measurement such as grams or ounces, so pay attention to the adjectives used in the fabric description.

If a fabric is described as “well-draped,” it is more fluid, falling gracefully and easily fitting the body. These types of fabrics are perfect for flowing garments like skirts, dresses, and loose blouses.

For example, the sample on the left is a polyester velvet with a weight of 420 g/m². It is described as having a ‘medium’ drape and is suitable for trousers, more structured dresses (e.g. pinafores) and lightweight jackets.

The sample on the right is a velvet blend of rayon and silk, weighing 150 g/m². It is described as having a “very good” drape. This fabric is suitable for casual dresses, loose-fitting trousers and outerwear.

If a fabric is described as having "body," it is firm and has little drape. It can be shaped to the body with seams and darts, making it ideal for structured garments like jackets or trousers.

For example, both of these examples are 100% silk. The organza on the left has less drape — meaning more body — while the chiffon on the right has more drape. Organza is 69 gsm and is characterized by a crisp drape for voluminous silhouettes. Chiffon is 34 gsm and is described as light and elegant.

Guide to Choosing the Right Casting

Before you shop, describe what kind of cast you want for your project — even jot down a few words. Words like fluid, loose, and form-fitting are good for “good casting.” For less casting, use descriptions like firm, bulky, and crisp, and note that it “has body.” If you want something in between, write “medium casting.”

When looking at fabrics, ask yourself these questions:

• Does the fabric have enough drape to flow the way I want it to?

• Is the fabric stiff enough to give me the structure and stiffness I want?

One last tip — you can use interfacing to give fabric a more structured drape, but you cannot make existing fabric drape more.

Weight and Casting Table

This chart shows how these two elements interact by placing different fabrics according to their weight and drape. For example, organza is light and sheer but quite stiff, while lightweight fabrics like chiffon have a high drape. Denim comes in a wide range of weights but is generally not very drapey unless rayon is added. Heavyweight and fluid fabrics include options like wool crepe and Tencel.

Please note that this chart reflects averages. Not all fabrics will always be in the same spot, but this chart is a good starting point.

Example: Knitted Fabric Samples

These knitted fabric samples demonstrate how weight and drape interact.

The double knit fabric on the left is a blend of 95% polyester and 5% spandex and weighs 620g/m². It is described as 'heavyweight', soft to the touch and flexible to drape. Note that there are no wrinkles when hung, but the fabric does sag slightly.

The pink French terry fabric is a blend of 66% bamboo, 28% cotton and 6% spandex and weighs 270g/m². It is described as 'medium weight', comfortable and extremely soft to the touch. Note that it does not fold in on itself and has a structured feel.

The next fabric is 100% organic cotton jersey and weighs approximately 236 g/m² (6.96 oz). It is described as lightweight, soft to the touch and has a very formable drape. Notice the folds that form when hung; this is a sign of good drape.

This “tissue-weight” jersey fabric is 100% cotton and weighs 52 g/m². It has been described as “extremely lightweight,” translucent, airy and flexible. It forms small folds when hung—much more drapey than the previous jersey.

But what if the online description of the fabric is not sufficient?

Now you know how stores specify the weight of fabric and describe its drape. If the fabric store you’re shopping at uses strong descriptors like “luxuriously fluid drape,” you can easily visualize how the fabric will work for your project. But what if you’re shopping at a store that only lists fabric content and no other adjectives?

Then you need to look for clues in photos of the fabric.

This Spoonflower poplin fabric has a very structured drape. Notice the large, structured pleats. You can also see that the fabric seems to lift slightly on the table, indicating its light weight.

Ideally, the store will show the fabric hanging, crumpled on a flat surface, or at least folded. If you see small folds, this may indicate that the fabric has drape. Larger folds — or no folds at all — indicate that the fabric has less drape and more structure.

This Spoonflower crepe de chine fabric has small, delicate folds that make it appear to flow slightly. This means that the fabric is lightweight, drapes well, and has a more body-hugging feel than poplin.

If the folds appear soft, the fabric is more drapey and will likely hug the body. Conversely, if the folds appear hard, the fabric is less drapey and will sit away from the body, maintaining its structure.

When the same two Spoonflower fabrics are laid out on a mannequin: the cotton poplin on the left does not drape as much as the polyester crepe on the right.

If the weave of the fabric seems loose or floats on the table, it is probably lighter. If the weave seems tight or the fabric lies flat on the table, it is probably heavier. But remember: drape and weight can sometimes be deceiving!

The More Samples, The More Information

It’s hard to learn all the characteristics about a fabric—fiber content, weave or knit type, stretch, weight, drape, handle (hand feel), and sheen. But the good news is that online fabric stores have gotten better at providing creative descriptions so you can imagine the fabric without actually touching it.

Here are a few suggestions to further enhance your fabric knowledge:

• Get a fabric book. Our favorites include Fabric Savvy: How to Choose & Use Fabrics by Sandra Betzina and Fabric for Fashion: The Complete Guide by Amanda Johnston and Clive Hallett and its companion sample book.

• Start a swatch journal. All of the fabric swatches above were purchased from Mood Fabrics, which has very vivid descriptions. You can create your own fabric swatch journal by ordering a few small samples with each fabric order.

• “Interview your fabric.” Conduct a mini-interview with a potential fabric using the questions above. Make sure the fabric’s online descriptions match what you’re looking for.