What Is Sport Weight Yarn?

Yarn categories can cause some confusion and a question we get asked often is "what is sport weight yarn?". With a new sport weight yarn hitting our shelves, Isager Eco Melange, I thought now would be a good time to delve into that question!

The short answer is it is in between a 4-ply and a DK weight yarn in thickness. We have a section for yarns we'd suggest for Sport Weight patterns if you want to go straight to that:

But if you want to go a bit deeper into it, read on...

Yarn weight categories are not absolute and people are increasingly seeing patterns from the US with terms like fingering, sport weight and worsted that are less commonly used in the UK so it can all get a bit confusing.

Let's talk 4-ply for a moment because most of us are familiar with that term. Different yarns within the same yarn weight category can vary fairly noticeably in thickness. Two yarns marked 4-ply can feel quite different and have a different meterage - 425m, 400m and 366m per 100g are all common. Those "4-ply" yarns may also be called "fingering weight" and people often try to identify differences between the terms. I have one friend who says fingering is a heavy 4-ply and another who says it is a light 4-ply. As far as I can tell 4-ply is just used more commonly used in the UK and fingering more commonly used in the US. The reality is that these terms are often interchangeable and within any yarn weight category there is a lot of variance anyway. Where does a "light 4-ply" become a "heavy lace weight" and where does a "heavy 4-ply" become a "sport weight"? That's often just down to what the producer has decided to put on the yarn label and sometimes we need to look a bit beyond that (although obviously it's generally a good starting point!).

But enough (almost) about 4-ply because I'm here to talk sport weight yarn. I say almost because some heavier 4-ply yarns tip into what I would consider a sport weight. 

Sport weight does specifically refer to a thickness somewhere between 4-ply and DK. Because sport weight has traditionally been used less in the UK we have heavy 4-ply and light DK yarns that work for sport weight patterns. 

Let's look at a few ways to think about this.

1) Sport Weight yarn is a 5-ply weight yarn.

First is the "ply" category. The amount of plies in a yarn is how many strands are spun together. Imagine in the spinning process that a single strand (or ply) of yarn is spun and then twisted together with another strand - thus making it 2-ply. Add in another strand and you have 3-ply. Another strand and we've made it to 4-ply. I think you get the idea. This is where the weight categorisations come from - with an assumption that one ply has a specific thickness (something akin to a very fine cobweb lace weight yarn). You may well have seen DK yarn referred to as 8-ply - eight one-ply strands spun together. BUT - and here's where some people's confusion comes from - whilst the ply-thickness categories have stuck they no longer necessarily refer to the actual number of plies in a yarn. So a 4-ply weight yarn can have any number of plies but will be the equivalent thickness of four 1-ply strands. A DK will be the equivalent thickness of eight 1-ply strands. 

So if you see sport weight referred to as 5-ply (or even 6-ply) this is to give a guide on the thickness but not necessarily how many individual twisted together plies the yarn is made from.

A quick mention that single ply yarns have become increasingly popular over the last few years but are not necessarily equivalent to a 1-ply thickness and could be anything from a lace weight up to a super chunky roving type yarn.

2) Sport Weight yarn is approximately 14 wraps per inch (WPI)

Let's look at wraps per inch (WPI). This is how many times a strand of yarn will wrap (not too tightly) around a ruler or something similar over a one inch width. This is a useful tool if you are trying to figure out what that mystery yarn that has lost its label at the bottom of your stash was. The guide for a sport weight would be around 14 wraps per inch. If we compare that to a 4-ply which would be about 16 and a DK which would be around 11-12, you can see how a sport weight sits in between 4-ply and double knit weights.

3) Sport Weight yarn works to a gauge of around 24-26 stitches per 10cm.

When it comes to a sport weight gauge, again we can see it sits between a typical 4-ply (around 28 stitches per 10cm) and typical DK (around 22 stitches per 10cm). With the increase of access to patterns on the internet from independent designers in the US, we are seeing more and more customers looking for a yarn to suit this gauge, and more UK designers are using it too.

N.B. A reminder that none of this is an exact science. The important thing if you want to get good results with a pattern is that you get gauge with your chosen yarn and are happy with the fabric it produces. The best way to check this is with a swatch (taking the gauge after the swatch has been blocked).

Here are our favourite yarns that are suitable for sport weight patterns.

You can look beyond these yarns and play around. It is perfectly possible to substitute a 4-ply yarn into a sport weight pattern if you like the fabric at that gauge, which is possibly going to be looser with more drape than the original pattern. This can work really nicely for warmer weather garments. You could also swap in a light DK, maybe resulting in a slightly denser fabric. Again, it's all about that washed and blocked swatch and what it tells you - if you get gauge and like the look, feel and drape of the fabric, you're most likely going to get a finished object you're happy with.

So my key suggestions for finding a suitable yarn for a sport weight pattern are:

1) Check the suggested gauge for the yarn you want to use (ask us if you're not sure but this is often on the ball band and in our product description). If the suggested gauge is close to or the same as the pattern, that's a good sign.

2) Check the meterage of the yarn you're considering using in comparison to the yarn suggested in the pattern. Do bear in mind if you're looking at a different sort of fibre (i.e. cotton instead of wool) the meterage could be quite different so cross reference with gauge.

3) Make a decent sized swatch and wash/block it as you intend to with the finished item. Once it is dry measure the gauge. If your gauge is too tight, try a larger needle, if it's too loose try a smaller needle. Once you achieve gauge, think about if the fabric you've got will suit the project. 

If you're happy with all that, GO FOR IT!

I'm planning more in-depth posts about swatching and yarn substitution soon so keep an eye out for those if you want to know more on those topics.

My Campfire Shawl pattern uses BC Garn Summer In Kashmir, a lovely organic cotton/cashmere sport weight yarn. We have kits in a great range of colours:

 If you have any more questions about sport weight yarn, just drop me an email: info@allabouttheyarn.co.uk