Understanding Denim Weights

Full Frame Shot Of Jeans
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Denim is a cotton textile that is probably most associated with blue jeans. The most common color of denim is indigo, which is made using blue and white threads. Denim was originally dyed with a dye produced from the Indigofera tinctoria plant, although most denim today is created with a synthetic dye. To color the yarn, the fabric is dipped repeatedly until the depth of blue is achieved.

Purchasing jeans or denim online can be a little tricky because all denim is not the same. Denim is sold by weight, so a yard of five-ounce denim weighs 5 ounces. Denim runs from 5 to 32 ounces. The lower the number, the softer and more flexible the fabric, while the higher numbers are heavier and stiffer.

Denim can be blended with other textiles like rayon and spandex to make a stretchy material that many feel is more comfortable to wear. When buying denim always read the swatch label. Each swatch is labeled with the fabric information, fiber contents, care instructions, and the width. Almost all online retailers offer fabric swatches.

Learning the Difference in Weight

When choosing the right denim for your project, consider the needs of the garment. For example, 20-ounce denim is not going to bend and move for most garment uses. Five-ounce denim is not going to provide heavy enough denim for jeans or jackets, however, it will make beautiful shirts, skirts, and dresses that will drape well. Knowing that denim runs from 5 to 20 ounces and that the less the weight, the lighter, softer, loft the denim will have, you can purchase or request samples of the weights you believe are in the scope you are looking for.

With this knowledge, you can assume 8-ounce denim is just a tad more pliable and softer than the 9-ounce. The 9-ounce sample is just a tad more pliable and softer than the 10-ounce sample. Durability-wise, they are pretty much identical. The real difference is the fabric's drape and flexibility.

Traditionally, 12 to 14 ounces is used for denim jeans. It will not ruffle or drape, which is something to consider if you are making a full skirt, say, for square dancing. If you want to make a strong, stand-on-its-own type of tote bag, then you want denim that is 10 ounces or higher denim. If you want the ability to fold the bag and have it for when you need it, you can go down to 6-ounce denim. The choice in bag fabric should be driven by what you want the bag to do.

This tote bag is standing on its own (nothing is in the bag). It is made with medium-weight denim.

Before Using Different Weights

Always pre-wash your fabric and if you are mixing fabrics on one garment, make sure that they can use the same laundering method.

Using a denim spandex blend is great for making comfortable everyday wear. However, this fabric wears out quickly. If your goal is a comfortable garment that will last, you might want to use a more durable fabric like jersey cotton.