Merino Wool GSM Explained
Posted on 22 January 2020
What is GSM and what does it mean when trying to buy clothing?
GSM stands for Grams per Square Meter. It is the overall weight of the fabric. By stating the weight, we are giving you the best indication of how heavy or light the garment is.
This said, it is hard to judge when you've never shopped by GSM before, and it is hard to know what to expect. Hopefully below will give you a much better idea.
Base - White Overlay at 80% - Black Overlay at 80%
165gsm - 180gsm - These are considered light weight merino wool. Depending on the weave and colour of the garment, you might be able to see some skin colour, though no details.
Our Ivory Short Sleeve Shirts for example are light weight - If I look up close, then yes, I can see skin colour, but not details (~85% opacity) - Far away, you'd have a hard time seeing skin at all. The Black & Charcoal rib knit SS Shirt however, looks opaque until it starts to get really small on them and stretched out.
Our adjustable leggings are a rib knit - so when unstretched, they are opaque. When stretched, depending on the level of stretchiness, it might end up around 80-90% opacity, with 80% being totally stretched out. I honestly didn't notice it on my kids at all when they were babies and toddlers. I did start noticing it when it was getting small on them, and they had contrasting underwear on. Like in the GSM pictures above.
This weight is great for when you want a light weight layer, or something light in the warmer months.
For more reference, regular cotton tshirts and light leggings are in this range (not the light weight tshirts - those are more 140gsm ) Merino wool however keeps you warmer when it is cool out, and cooler when it is super hot out than its cotton counterpart.
190gsm - 220gsm - These are considered mid weight merino wool. Most base layers are made from mid weight merino. If you've ever had any type of base layer, you'll know it is typically thin, and when stretched and at the lower end of this scale, you might be looking at 90% opacity (usually plain white you'd notice there is something black underneath when stretched, but hard to find shape at all) At the high end of this scale it acts more like heavy weight, and you start to notice it is a bit thicker. It is the typical weight of many of our products as it is versatile, and a good all season option.
For reference, our cotton adjustable leggings also fall in this category. Thin enough for everyday wear, thick enough that you won't see anything.
For more reference, thick cotton shirts fall under this category.
230gsm - 320gsm - This is considered heavy weight merino wool. This is where you start to see the properties of merino wool and the different weaves get interesting and why it is hard to quantify thickness at this point.
For example, our Carbon Stripe Merino hoodies are 320gsm. But are thinner in feel than a typical cotton fleece hoodie or our Mountain Hoodies at this same weight . The merino hoodie will outperform the cotton one in temperature range as well. When kids take off hoodies because they are too warm, they may not with the merino wool one because it helps regulate their temperature, and they may not feel as warm (it also wicks away sweat really well) Think of sheep on a hot day... they still have coats of wool...
Our Merino Pocket Pants, Merino Dungarees, Heavy weight Merino Adjustable Leggings, and Cotton Dungarees are also in this range,and more!
330gsm - 600gsm - This is the outerwear weight.
Most of our felted merino wool products are all roughly 600gsm. We take 300gsm merino wool, and felt it up to be 600gsm. So effectively it is like having double the fabric of a heavy weight - it is also why the felted merino wool products are pricier.
This is a weight I'd want on a snowy day. Our Winter Mitts and Winter Bear Hats are all out of this 600 gsm weight. Merino wool also keeps you warm when it is wet! Go merino!
We also have our felted organic merino wool Adjustable leggings in this range - one of the heaviest leggings you can get for bigger kids! - They are approx 450gsm.
Some examples of layering and weights:
Example 1: People layer garments to achieve this type of weight. Like a base layer shirt (200gsm) and a hoodie (300gsm).
Example 2: Our merino wool Reversible Balaclavas have 1 layer of heavy weight, and one layer of mid weight giving you a total weight of approx 520gsm on your head.
Example 3: Our Reversible Jackets have 1 layer of heavy weight merino, and 1 layer of organic cotton giving a total weight of approx 490gsm
I hope this gives you a better understanding of GSM when shopping on our site. As always, if there are ever any questions - just email me!