Pull two hoodies off a rail. They look like the same garment, right up until you hold one in each hand. One has heft. The other, honestly, feels like it would blow across a car park. There’s a number sitting behind that gap — GSM, grams per square metre — and the brushed cotton fleece on the hoodies at Spiderscanada sits at 380 of them, which is a long way up from what a shopping-centre hoodie runs.
So what is GSM, roughly?
It’s the weight of a single square metre of the knit, taken before anybody cuts a pattern out of it. That’s all it is. 380 grams for this fleece, while the shop’s own FAQ reckons a typical high-street hoodie lands somewhere in the 280 to 320 band for the same patch of cloth.
Sixty to a hundred grams sounds like loose change. Then you start counting up how much cloth actually goes into a boxy hoodie — body, two sleeves, a hood, a kangaroo pocket — and you’re at something like two square metres, so the finished thing is hauling a couple of hundred extra grams about. You clock it the second it goes over your head.
Brushing does about half the work
Weight on its own would just hand you a stiff board. Brushing is what makes it wearable: the inside face gets raked until the loops open up into a nap, and that fuzz then holds a thin pocket of air against your skin. Do it to a thin fleece and the nap gives up after four or five washes (you’ve probably owned one that did). There’s enough yarn in a 380 GSM loop that it keeps standing.
| Fleece weight | Where you meet it | What it does over a season |
| 280–320 GSM | Most high-street hoodies | Drapes close, thins at the elbows early |
| 380 GSM | The brushed cotton fleece here | Holds its line, keeps its nap longer |
Weight is what keeps an oversized cut from flopping
Worth dwelling on, this one, because it catches people out. The block here is oversized on purpose — shoulder seam sitting well down the arm, boxy through the body, drawcord hood, ribbed cuffs. Thin fleece in that pattern just flops — seam creeping forward, body folding into itself — and you end up looking like you borrowed it rather than bought it.
Denser cloth has the body to hang off a shoulder instead of slumping off it. Hem falls straight. The sleeve keeps a bit of a tube to it rather than crumpling into your wrist. And on the zip-up web pieces, where a rhinestone set or a raised print is adding its own weight to the front panel, those extra grams underneath are what stop the graphic dragging the chest out of true.
The hood’s a different story too. A 380 GSM hood stands up when it’s down — small thing, but that’s the gap between a hood framing your neck and one puddling across your back.
Where the weight pays off in a Canadian winter
A damp Vancouver November is the honest test. The temperature barely moves, but the air sits wet on you all day, and a thin hoodie drinks that up and then starts pulling heat straight off your back. A dense nap hangs on to its warm air far longer in that kind of damp, which is roughly why this fleece reads as a jacket in October and a mid-layer come January.
Calgary at −15 °C asks something else of it. The hoodie quits being outerwear and turns into the warm layer under a shell, and what you’re planning around by then is bulk, since a fleece this dense eats room in a jacket sleeve. That’s the trade. More warmth, less give.
Comparing weights across both shops
Put two fleeces side by side before you spend anything — costs nothing, settles the argument. Spiderscanada has 63 hoodies across its web-print, rhinestone, puff and tonal families, while the catalogue over at Spidershoodies runs 59 under its own Spider Hoodie heading, so there’s a fairly wide spread of colourways sitting on more or less the same silhouette.
And read the listing, not the photo. A photo can’t tell you a thing about fabric weight. A listing that bothers to print a GSM figure at all is telling you something, though.
| Pro Tip: Before ordering, weigh a hoodie you already own on the kitchen scale. A size L at about 300 GSM tends to land near 600 grams, where the same size at 380 comes in nearer 750 — so a vague hunch about thickness becomes a number you can hold against a listing. |
Keeping a heavy fleece heavy
Dense cotton quietly rewards a lazy wash and punishes a hot one. The care note on these asks for cold water, inside out, no bleach, and hang drying instead of a tumble — and the hang-dry bit is the one everybody skips and then regrets, because dryer heat pulls cotton in across the width and crushes that nap flat in the same cycle. Skip the dryer. Seriously.
- Inside out keeps the print face off the drum, and off whatever else is in the load.
- Cold water stops the cotton pulling in across the chest, where you notice shrinkage first.
- Crystal-set pieces want a mesh bag, so the settings aren’t catching on a zip.
- Dry it flat, or over a broad hanger — a wire one leaves you two peaks in the shoulders.
A season of that and the hand feel has barely budged. A season of hot washes and the tumble dryer, though, and you’ve paid for 380 GSM but worn your way down to something nearer 320.
Frequently Asked Questions
Is 380 GSM too warm indoors?
In a heated flat, with a long-sleeve on underneath? Probably, yeah. Most people seem to use it as a commute layer through the colder half of the year, then drop back to a cotton tee indoors.
Does it shrink?
Cotton always wants to. Cold water and air drying keep that movement small enough you won’t spot it in the chest or the sleeve; hot water plus a dryer will cost you centimetres you can see.
Will the nap flatten under a bag strap?
A bit of flattening along a strap or a seat belt shows up on any brushed fabric, and a denser nap just takes longer to get there. Most of it lifts again after a wash anyway.
So, read the number on the label. A heavier fleece costs you a little packability and some room under your shell, and what comes back the other way is a hoodie that keeps its shape and its softness through more than one winter. Have a scroll through the colourways, see what weight the listing admits to, and go with the one you’ll actually grab at seven in the morning.

