Happy Friday, dear T.H.R.I.V.E. Association family! Some of our recent blog posts touched on demystifying yarn labels and explaining the Craft Yarn Council’s Standard Yarn Weight system. However, we’ve had many questions from several volunteers about yarn substitution and we’d like to answer some of those questions!

Yarn substitution is when you want to substitute a different yarn than the one recommended by the pattern that you are using. There could be many reasons why you might want to: you may want to avoid a certain type of yarn because of allergies or preference of fibers, you may want to use out yarns that are already available in your stash, or you may want to use a more economical option than the yarn suggested, etc. Either way, there are certain considerations that you must keep in mind when substituting different yarn(s). 

One of the first things to check, is whether the yarn company (e.g. Red Heart, Lion Brand) providing your pattern has a dedicated page on their website concerning suggested yarn substitutions. This may save you the time of trying to find a suitable yarn that will work with your chosen pattern.

The next consideration when choosing a proper yarn substitute is choosing a yarn that falls within the same weight (thickness) category in the Craft Yarn Council’s Standard Yarn Weight system. For example, if the yarn suggested in your pattern calls for a Worsted Medium (4) weight yarn, a good rule of thumb would be to use another Worsted Medium (4) weight yarn to substitute and not a different weight class of yarn, such as a DK Light (3) weight yarn or a Bulky (5) weight yarn. Any big differences might lead to a garment looking, fitting, and/or draping drastically differently than you might otherwise want. Note: the classifications in the Standard Yarn Weight system contain variance in thickness within each individual number. A common example of this would be choosing a pattern that calls for a certain Medium (4) weight yarn. A Medium (4) weight yarn could range from a true Worsted weight yarn all the way to a thicker Aran weight yarn. This could result in, for example, one brand’s Medium (4) weight yarn to be thicker or thinner than their own or another brand’s Medium (4) weight yarn.

Another important thing to consider when substituting is the length/weight, such as yards/grams, of the yarn. So if your pattern calls for a yarn that is 180 yards long and weighs 100 grams, you should endeavor to use a yarn that is similar enough to that ratio in both length/weight. In our experience, changing this too much does have a big effect on the finished garment.

The next things to consider when substituting are the fiber content and texture of the yarn. A 100% Acrylic smooth and shiny yarn will most likely look, feel, stretch, and drape differently than a 50/50% rough and fuzzy Alpaca Wool/Cotton blended yarn. Make sure to keep this in mind when substituting and, if you want to keep it simple, use similar enough substitutes to avoid unwanted impacts to the completed pattern.

Finally, it is always a good idea to make a swatch with your substitute before you dive into the pattern in order to test out if your substitute is going to work the way you and the pattern intend. You may find that you need to move up or down a needle or hook size, or you might even find that your yarn substitute isn’t suitable at all!

Whatever the case, whenever you choose to substitute a different yarn than what the pattern calls for, taking these considerations into account and testing them out in a swatch before you begin will help to ensure that your finished garment will much more closely resemble what the pattern details and you’ll assuredly be glad you took the time to plan/test it out!