The decision to ban PFAS-based chemicals from clothing was welcome for a number of reasons. While they do offer some excellent performance characteristics – especially in hi-tech, weatherproof clothing – these ‘forever’ chemicals can take 1,000 years to decompose and find their way into the life-cycle of living organisms, including the human body.

But what’s good for the planet in general terms might not necessarily be good for cyclists in specific moments when they find themselves excessively hot, or cold, or wet. So cycle clothing manufacturers and companies such as Polartec – who produce the high-performance fabric from which manufacturers make their garments – have been innovating at never-seen-before levels to come up with new solutions to the age-old question of keeping riders comfortable.

Hardcore AirCore

One of the first fruits of this endeavour is Polartec’s brand new AirCore fabric. 

AirCore, which has been developed for Castelli in partnership with Polartec, has been described as rewriting the gold standard of what high-performance cycling gear can do. It offers both water repellency from the outside but also allows incredible levels of breathability, and therefore protection from perspiration. 

Steve Smith, head of cycling at Castelli’s parent company, MVC Group, even went so far as to say: “It’s hard to fully explain how revolutionary AirCore fabric is. Its properties achieve something that’s never been done before.”

Polartec AirCore detail
Polartec AirCore (Image Credit: Polartec)

So what can it do? Firstly, let’s deal with weatherproofing, which is where those pesky PFAS chemicals really had in impact. In AirCore’s case, though, it is both essentially windproof and essentially waterproof – testing has shown rain would need to fall with 6.25 times more force than it usually does to permeate the fabric – without needing any PFAS.

Why use the word ‘essentially’? Well, in real-world conditions, AirCore’s abilities to hold back the wind and rain are truly impressive. However, unlike most other weatherproof fabrics, AirCore is not completely impermeable. 

Instead, it has been engineered to let in a very small, almost imperceptible amount of air. This leads to its ‘revolutionary’ breathability, with the air picking up perspiration-induced moisture and carrying it outside the garment, ensuring riders stay dry.

Unique approach

The technology used to engineer this performance is unique. The AirCore membrane is produced via a process called ‘electrospinning’, where a hydrophobic proprietary polymer is pushed through a hypodermic needle charged at 20,000 volts. Under pressure, it emits a thin jet of microscopic filaments – approximately 100 times smaller than a human hair – which fall like snow to create an incredibly tight membrane that still allows air to permeate it. 

The end result, Steve Smith at Castelli says: “has far exceeded what we ever thought possible. Not only have we developed a fabric that is off-the-charts in terms of breathability, it is also highly water repellent, lightweight and windproof, as well as being incredibly stretchy and comfortable.”

So let’s look at a trio of trailblazing garments that are the first to go into production with AirCore fabric.

Castelli Perfetto RoS 3 Jacket Men, Women – £280

Castelli Perfetto RoS 3 Jacket Men
Castelli Perfetto RoS 3 Jacket Men (Image Credit: Polartec)

Available in both men and women-specific designs, the Perfetto RoS 3 jacket is cut for comfort and speed, but now with the added element of AirCore breathability and weatherproofing. 

While the ability of the AirCore fabric is the obvious star of the show, the Perfetto RoS 3 does come with some other important additional features, such as: reflective taped shoulder seams for extra rain protection; zipped ventilation openings on the sides of the chest; top-and-bottom opening YKK Vislon main front zip for easy sliding, with additional wind and rain protection cover; three rear pockets with drain holes; longer tail to protect from wheel spray; reflective detailing at the pocket bottoms; and a high collar to guard against drafts.

The men’s Perfetto RoS 3 jacket is available in the following four colourways: Rich Red/Black Reflex, Light Black/Silver Reflex, Mocha/Black Reflex, Pool Blue/Black Reflex. 

The women’s Perfetto RoS 3 jacket is available in Hibiscus/Black Reflex, Pool Blue/Black Reflex, Mango Mojito/Black Reflex,  and Light Black/Silver Reflex. 

Castelli Alpha 150 Jacket Men, Women – £360

Castelli Alpha 150 Jacket Women
Castelli Alpha 150 Jacket Women (Image Credit: Polartec)

Castelli markets its Alpha 150 Jacket – again available in dedicated male and female fits – as being simply: “The ultimate winter jacket.”

It’s easy to see why the brand can say this with some confidence. Along with the groundbreaking outer layer of weatherproof and breathable AirCore, the Alpha 150 uses Polartec’s awesome Alpha inner liner, for heightened insulation with minimal excess weight, along with excellent moisture management. 

In addition, there’s a double-opening front to allow independent ventilation of the AirCore and Alpha layers; a top and bottom-opening YKK Vislon zipper with weather-protective cover; a high collar and double cuffs for extra warmth; a convenient zipped key or money pocket on front side; three rear pockets; and reflective piping at bottom of pockets. 

Built to excel in temperatures ranging from -2 to 10°C (28-50°F), this truly is the garment you want for winter riding. 

The men’s Alpha 150 jacket is available in Light Black/Black, Mango Mojito/Black, Brilliant Orange/Dark Gray, and Deep Bordeaux/Clay. 

The women’s Alpha 150 jacket is available in Light Black/Black, Depp Bordeaux/Brilliant Brilliant Pink, and Hibiscus/Black.

Sportful Fiandre 2 Jacket Men, Women – £240

Sportful Fiandre 2 Jacket Men 1
Sportful Fiandre 2 Jacket Men (Image Credit: Polartec)

Finally, Castelli’s sister brand, Sportful, has also got in on the AirCore action with its fantastic Fiandre 2 Jacket: the most advanced winter cycling jacket the company has ever made.

Created to meet the demands of committed cyclists riding through the coldest months of the year, the Fiandre 2 Jacket has been designed for fast-paced training or racing in windy, rainy and cold conditions. 

As well as its AirCore powers, the Fiandre 2 also features a dual zip for easy ventilation on the move; pockets with object retention technology for added security; and the ability to be used all the way down to -5°C.

The men’s Fiandre 2 jacket is available in Black, Teal Blue, Bright Orange, and Gold Leaf. 

The women’s Fiandre 2 jacket is available in Black, Pompelmo, and Teal Blue.

For more information about Polartec’s AirCore fabric technology, head to Polartec’s website