As a follow-up on my earlier post about yarn weights, I wanted to also address, and hopefully demystify, the practice of knitting with yarn held double. Because while it is fairly obvious that holding a yarn double will result in a yarn twice as thick as the original, it is perhaps less obvious what yarn weight exactly the result will translate to.
Happily, figuring this out is fairly simple, and here is how to do it:
Step 1: Check the meterage info (meters per 100g) on the yarn label or product description.
Step 2: Divide that number by 2.
Step 3: Armed with the resulting figure, consult my Handy Chart of Yarn Weights
Let's take some concrete examples:
Yarn which is 800m per 100g, held double, will yield a meterage of 400m per 100g, which is that of a fingering weight yarn.
Yarn which is 400m per 100g, held double, will yield a meterage of 200m per 100g, which is that of a DK weight yarn.
Yarn which is 300m per 100g, held double, will yield a meterage of 150m per 100g, which is that of an aran weight yarn.
And so on.
Now, if dividing by two is too much math for you to cope with, do not despair! For I have made a cheat sheet (above).
However: If you want to be precise, I still recommend checking the actual meterage - for reasons I have explained in the previous post.
Being able to do this kind of 'translation' is of course very handy when it comes to yarn substitutions. For instance, say a pattern calls for a DK weight yarn, but you don't have any in a suitable colour/ composition - yet you have the perfect fingering weight yarn, you know that you can hold that fingering weight yarn double to achieve the yarn weight the pattern calls for.
Conversely, let's say a pattern - like my Harvest Season hat - calls for a fingering weight yarn held double, but you don't have any suitable fingering weight yarn. You check the pattern info and see the suggested yarn has a meterage of 420m per 100g. Held double, that is the equivalent of 210m per 100g, or DK weight. You can therefore knit this hat with DK weight yarn, held single stranded.
All that being said, a couple of things to be aware of:
A yarn weight achieved by holding a thinner yarn double, may not feel or behave exactly like a yarn that was spun and plied to that weight to begin with. In some cases the resulting fabric will be ‘flatter.’ In other cases, quite the opposite - it can feel overly thick or puffy. Without getting too technical, this is to do with ply and twist and the way air gets trapped between strands, and all manner of other fascinating things related to spinning. So before you decide to substitute, say, an aran-weight yarn a pattern calls for, with a sport weight yarn held double, be sure to swatch at the stated gauge and just see whether you like the way the fabric is knitting up.
Aside from this, some knitters claim that knitting with yarn held double is ‘not economical' as far as meterage. However, I believe this idea is based on a misguided comparison to knitting with the yarn held single! Once you hold the yarn double, of course it’s no longer going to yield the meterage stated on the label; it’s going to yield exactly half that meterage - which makes it no more or less economical than knitting with a yarn of the weight we are aiming for.
Basically, by holding a yarn double, we are converting it to a yarn that is twice its original thickness and half its original meterage. As long as we grasp that principle, all will be well!