What does heavy weight mean in clothing?

16 Apr.,2024

 

There’s just something about sweater weather that feels so inviting. As the rainier and colder seasons approach, the urge to buy a cosy new sweatshirt gets strong. 

Yet, in a market saturated with a gazillion types of sweaters, quality and sustainability should be prioritised over buying on impulse. So, what should the seeker consider while on the lookout for the perfect sweatshirt?

Don’t overlook the weight!

One of the most important characteristics to keep an eye out for is the sweater’s weight. 

Why is this so important? Fabric weight influences the comfort of the sweatshirt, depending on the conditions. If the fabric were super thick, you’d swelter on a hot evening. 

But brands don’t talk about fabric weight as often as they should. With more brands selling exclusively online, it’s hard to judge the feel of an item. And even if you get the opportunity to try before you buy, not everyone can detect which is best for the cold versus the heat, or whether the sweater will keep you warm and toasty. So when you do see the words ‘GSM’, ‘heavyweight’, ‘lightweight’, or related, it’s a sign that the product is being described in detail to help you find the perfect garment. A green flag.

But what does GSM in fabrics mean?

GSM refers to ‘grams per square metre’ and it’s used to measure the density of a fabric. 

The higher the GSM, the heavier and more durable the fabric. The lower the GSM, the lighter and more breathable the fabric. The measurement helps determine the best weight of a material - depending on its function. 

GSM also determines the informal classification of a garment as lightweight or heavyweight. Unsurprisingly, garments made from higher GSM fabrics are referred to as heavyweight. Lower GSM clothes are referred to as lightweight. So, you’ll want to wear a heavyweight garment on colder, winter days, and a lightweight garment on warmer, summer days.

To give you a bit more perspective, heavyweight fabrics typically include canvas, suede, and wool. Examples of heavyweight garments are denim jeans and bath towels. At the lighter end of the scale, you’ve got fabrics like linen, lace, mesh, and silk. Think summer dresses and silk bed sheets. Nevertheless, each type of fabric can also come in lightweight or heavyweight versions. It can be a relative description. Even a ‘heavyweight’ linen can be lighter than regular denim.

It’s important to note that the GSM numbers determining whether a fabric is heavyweight or lightweight will also differ based on garment type. T-shirts, for instance, have lower GSM numbers overall. When it comes to sweaters, look for the following GSM figures:

Heavyweight sweater: 300-400 GSM
All-season sweater: 250-300 GSM
Lightweight sweater: 150-250 GSM

Heavyweight vs. Lightweight Cotton Sweaters

Since there are many different types of cotton, cotton comes in a range of different GSMs. It can depend on the type of cotton plant - plus the weaving, knitting, or felting process that the fibre goes through before transforming into the end fabric (i.e. corduroy, canvas, oxford, sateen, etc.).

Let’s take a closer look at each type of sweater you can find and compare some key characteristics.

Cotton by Home of Wool

Heavyweight cotton sweaters:
• are thicker and denser
• retain heat better and keep you warm
• are durable and can withstand many washes
• are best for cold weather
• range from 300-400 GSM

Heavyweight cotton sweaters tend to be more expensive than lightweight cotton sweaters since more raw material is used. But they also have a reputation for lasting longer. They’re best for wintertime, or for that person you know who always complains about being cold. Cotton reigns supreme for heavyweight sweaters due to its natural breathability, whereas synthetic materials often induce significantly more sweat.

Lightweight cotton sweaters:
• are airy and breathable
• keep you cool and stop you from getting sweaty
• are best for mildly cool temperatures
• range from 150-250 GSM

Lightweight cotton sweaters are perfect for those chilly summer evenings when you want to watch the sunset on the beach but they can also be worn as a base for layering up. They’re porous, so they’ll let air move through and won’t trap sweat in. Lightweight sweaters will be less sturdy and more ‘flowy’. They’re easier to travel with as they don’t weigh too much, giving you the perfect pullover to pack in your bag when you have a long day outside.

All-season cotton sweaters:
• are versatile and more useful to have all year round
• can be worn in various seasons
• are ideal for the transition between the extreme cold and heat
• range from 250-300 GSM

If you’re looking for a go-to sweater that you can wear throughout the year, an all-season sweater with a GSM range of 250-300 is your best bet. With this fabric weight, you’ll be warm in mild temperatures and able to layer up for more extreme temperatures. If you fancy an oversized fit, you can layer with a lightweight sweater underneath - or if a standard fit’s more your thing, wear a jacket over the top. 

Why so much cotton?

You might be wondering, why are we banging on about cotton?

Well, organic cotton is what we use, exclusively, but cotton is also by far the most popular fabric for sweatshirts. With good reason. Cotton is a breathable fabric, so less likely to trap moisture - especially in heavyweight form. And when it comes to lightweight sweaters, cotton is an ideal material that provides breathability for your day-to-day as well as for sports. Not to mention that it’s soft, absorbent, non-transparent, and affordable. 

Cotton is also far easier to maintain and wash than fabrics like cashmere or wool. Nevertheless, some other materials besides cotton are also excellent for lightweight sweaters, such as linen and lyocell. Lyocell in particular is known as a top choice for lightweight garments because of its high durability, despite its graceful lightness. It’s also one of the most sustainable fabrics out there. 

Lyocell is nowhere near as popular as cotton for sweatshirts, though, but it’s on the rise. Mind you, cotton isn’t going anywhere either.

Sweaters at POMP

Here at POMP, we offer a range of sweaters, designed to be worn all year round. We use a versatile 300 GSM, 100% GOTS-certified organic cotton fabric to guarantee durability, sustainability, and high quality. Our focus is on timeless organic basics in a range of lovely colours.

A 300 GSM sweater made from 100% organic cotton.

And for those who want to go the extra yard for sustainability, we offer the same sweater in a recycled version - made from 50% post-consumer remanufactured organic cotton and 50% virgin organic cotton. You can even send it back for recycling once you’re done using the QR code on the label. 

A 300 GSM sweater made from 50% recycled organic cotton and 50% virgin organic cotton.

If you think T-Shirts are only for light and hot summer days, then you’ve probably never worn a heavyweight T-shirt. Because a heavy T-shirt is not only heavier, it is also much thicker and warmer. Depending on the material, density and weight of a T-shirt, you can wear the fashion classic in autumn and even in winter – provided it’s a premium quality product. But what is a heavyweight T-shirt anyway and how can you distinguish it from other types of tee? At SANVT, we explain…

GSM – Your measure of a heavyweight t-shirt

When we talk about heavy t-shirts, one unit of measurement is crucial and that is obviously the weight, measured by the GSM number. GSM stands for “gram per square meter” and simply gives information about how much a fabric weighs per square meter. The GSM number – often marked as “g/m²” – describes the weight of a garment in a standardised way. So the higher the GSM of a material, the thicker and heavier the t-shirt. Sounds logical, doesn’t it?

Therefore, if you are looking for a heavyweight t-shirt for cooler days to withstand wind and weather, you need to look for as high a GSM as possible. But what exactly is considered to be a high GSM?

How much GSM is needed?

If this is the first time you’ve read about GSM, you probably don’t have any reference for what the ideal number for a heavyweight t-shirt should be. Generally, the rule of thumb is that heavy premium t-shirts for winter should have a GSM of at least 200. To put this in perspective: the standard weight for versatile and trans-seasonal t-shirts that can be worn all year round lies between 160 and 200 g/m². Whereas special summer t-shirts made of ultra-fine fabrics have a GSM number of less than 160. And although these numbers don’t seem like they make much of a difference, they are absolutely crucial and significant!

What else should you look out for?

However, finding out the GSM number of a t-shirt is easier said than done. Many brands – especially fast fashion companies – do not even bother to indicate the weight of their fabrics. In any case, we recommend slow fashion brands that really consider the choice of material, durability and design. Because only when a t-shirt is also sustainable, durable, high quality and fairly produced can it be considered a true premium product.

A heavyweight t-shirt should therefore ideally be made from natural materials to ensure its breathability despite the dense, heavy fabric. We also recommend 100% cotton t-shirts. This is because blended fabrics with polyester lose microplastics when washed (which in turn makes them no longer sustainable). To avoid unwanted linting, we recommend t-shirts with pre-wash and so-called ‘anti-pilling’ to protect the fibres of the material in the long run.

Our heavyweight t-shirt worn by Sonny. 

A different t-shirt for every season

At SANVT, we are passionate about sustainable basics. And we are particularly fond of the iconic t-shirt! That’s why we’ve created three versions of this perfect essential. The lightweight t-shirt is made from a luxurious mix of premium cotton and the biodegradable cellulose fibre Lyocell. With a GSM number of 160 and an excellent breathability, this t-shirt is ideal for light summer days.

In addition to our summer t-shirt, we’re continuously developing the king of all basics: the perfect t-shirt made of 100% ELS cotton. With its GSM number of 185, this classic is a versatile all-rounder for every season. A cross-seasonal basic that always works.

The heavyweight t-shirt from SANVT

Last but not least, we have developed the heavyweight t-shirt, which is made of 100% finest cotton with a GSM number of 235. This extra heavy t-shirt is ideal for cold days as it offers increased thermal insulation, durability and longevity. Thanks to the specially designed knit structure of the material, our t-shirt has outstanding thermoregulatory properties without losing its breathability.

Our reinforced, bound round collar also gives the premium t-shirt a robust, elegant character. The heavyweight t-shirt by SANVT is also GOTS-certified and not only extra heavy and sustainable, but also incredibly durable and fabulously soft!

Talking about sustainability: all of our t-shirts – whether lightweight, perfect or heavyweight – are produced sustainably, climate-neutrally and fairly in Portuguese family-run businesses. Our custom sizing concept also allows you to choose our t-shirts by width and by length, so the fit feels pretty much tailor-made. SANVT’s heavyweight t-shirt is available in classic white, sophisticated black or elegant midnight blue. The collar of the heavyweight tee has a bound neckline with a twin needle stitch.

Conclusion

An extra heavy t-shirt for cooler days is a timeless basic that everyone should have in their wardrobe when temperatures drop below 15 degrees. A premium heavy-weight t-shirt should not only have a GSM number of over 200, but it should also be produced sustainably and fairly. Only then should a product be considered premium quality – according to our standards! And once you’ve found your perfect heavyweight t-shirt, it’s guaranteed to serve you for many years in chilly temperatures as part of cool layering looks. After all, who says you have to compromise on style when it’s cold outside?

Read more about the differences between light and heavy t-shirts here.

What does heavy weight mean in clothing?

What is a heavyweight t-shirt?