If you have spent any time shopping premium streetwear online, you have seen the numbers. 500GSM. Heavyweight fleece. 400GSM cotton. They get printed on product pages like a badge of honour, but rarely explained. If you are comparing a VELLURE tracksuit against something cheaper and wondering what you are actually paying for, this is the plain-English version: what GSM measures, what 500GSM feels like in the hand, how to read a spec sheet without being misled, and how to get a fit that still looks sharp a year from now.
What does GSM actually mean?
GSM stands for grams per square metre. It is a measure of the weight of the fabric, not the weight of the finished garment. One square metre of the material is weighed, and that number is your GSM. Heavier fabric usually means a denser, tighter knit with more cotton packed into every centimetre, which is why GSM has become a shorthand for quality in the premium end of UK streetwear.
For context, a basic high-street tee often sits somewhere between 150 and 180GSM. A mid-weight hoodie is typically 280 to 350GSM. Once you move past 400GSM you are in heavyweight territory, and 500GSM is the top end of what most brands are willing to make, because denser fleece costs more to knit, more to cut and more to sew - and it is genuinely heavier to wear.
The number on its own is not a quality guarantee. It tells you density, and density is the starting point for everything else: how the garment drapes, how it holds its shape and how long it survives a British winter.
What 500GSM feels like when you put it on
Weight is the first thing you notice. A 500GSM piece has a substance to it that mid-weight fleece simply does not - it sits on the shoulders rather than clinging to them, and the fabric moves as one piece instead of stretching thin across the chest.
The second thing is the structure. Dense cotton fleece holds a clean, boxy line, which is why heavyweight hoodies and tracksuits photograph so well and why they suit the relaxed, regular fits that define good streetwear. It does not sag at the hem or collapse at the hood after a few washes. That structural memory is the real reason people seek out 500GSM in the first place.
The Grey Acid-Wash 500GSM Signature Hoodie is VELLURE's clearest example of the weight class in practice: a limited-edition heavyweight piece where the density is what carries the acid-wash finish and the clean silhouette.
How to read a 500GSM spec without being misled
A few things are worth checking before you commit:
- Fabric vs garment weight. GSM describes the fabric. A 500GSM hoodie is not a five-hundred-gram hoodie. Any page that blurs the two is worth a second look.
- Fibre content. Heavyweight cotton fleece and heavyweight polyester blends behave very differently. Cotton fleece breathes, softens with wear and keeps its shape; cheaper synthetics can feel heavier without the same comfort. Look for a clear fibre content rather than vague "premium blend" wording.
- Construction details. Dense fabric needs good seams, ribbed cuffs and a well-finished hem to hold its shape. The specs should mention them.
- The cut. Heavy fabric with a flimsy cut is still a flimsy garment. Look for a stated fit - regular, relaxed, slim - and check the actual measurements.
Why heavyweight fleece suits UK weather
A mid-weight layer is fine for a mild day, but it stops working when the temperature drops and the wind picks up. Dense 500GSM cotton fleece traps more air inside the knit, which is exactly what keeps you warm without a bulky outer shell. That makes heavyweight tracksuits and hoodies the practical choice for most of the UK year: warm enough on a cold morning, breathable enough to wear indoors, and substantial enough to layer under a windbreaker without the whole outfit turning shapeless.
If you want a technical layer for wet and windy days rather than cold ones, a lightweight contrast windbreaker set is the better partner to keep in your rotation.
How to get the fit right
Heavyweight garments behave differently from thin ones, so treat sizing as its own decision:
- Check the stated fit. A regular fit in 500GSM cotton fleece will already feel roomier than a regular fit in a light jersey, because the fabric does not cling.
- Measure a garment you already own. Chest width and body length tell you far more than a letter size, especially across brands.
- Decide on your drape. For the classic streetwear look, allow a little space through the chest and let the hem sit just below the hip. For a sharper, closer line, size to your measured chest.
- Match the set. Tracksuit bottoms and hoodies are cut to work together, so check that both pieces are the fit you want if you are buying the full look.
You can see the full range of heavyweight and fleece sets on the VELLURE tracksuits collection, and the individual hoodie fits on the VELLURE hoodies collection.
Caring for heavyweight cotton fleece so the drape lasts
Dense cotton fleece is built to take some punishment, but a little care keeps the structure intact for years rather than months:
- Wash cool and inside out, with similar colours, and avoid overloading the machine.
- Skip the tumble dryer where you can. High heat is the fastest way to shrink cotton fleece and soften the shape you paid for.
- Dry flat or line dry in the shade to protect both the colour and the knit.
- Fold rather than hang heavy hoodies. A wet 500GSM garment on a hanger will stretch at the shoulders and lose its line.
Look after the fabric and a heavyweight piece actually gets better with age: softer to the touch, but still holding its shape.
How to check price and availability
Heavyweight pieces are made in smaller runs, and limited drops sell through quickly. Because pricing and stock vary by size and colourway, always check the live product page before you buy - that is the only place where the current price and availability for your size are guaranteed.
The takeaway
500GSM is not a marketing number, it is a density rating - and density is what gives a premium tracksuit its weight, its drape and its staying power. Read the fibre content and the construction, not just the headline figure. Get the fit right by measuring rather than guessing. Then look after the fabric so it keeps its shape through the season and beyond.
Vision over noise applies to fabric too. Fewer, heavier, better-made pieces will always outlast a drawer full of thin ones.