Drawing on decades of mountaineering and product testing, Hervé Barmasse explores how technical shells have evolved to offer greater comfort, weather resistance, and safety.

Yet while technology continues to advance, experience, judgment, and respect for the mountains remain the most essential tools of all.

When I started climbing, mountain clothing and equipment were undoubtedly cutting-edge for their time, but still a long way from today’s standards. My jackets weighed nearly twice as much as modern ones, became stiff in the cold, and were often far from breathable. Even details such as zippers, closures, and seam construction, although carefully designed and refined, were very different from what we know today. As a result, on the windiest days, during snowstorms, or when a freezing bivouac lay ahead, the smartest strategy was often a timely retreat, waiting for better conditions before attempting the ascent again.

And even earlier, during those formative years when I would do anything to get into the mountains or join an expedition, despite having almost no money, it was common to repurpose gear from other sports for mountaineering. I still remember wearing a wool sweater instead of a down jacket on my first winter ascent of the Matterhorn, simply because a proper down jacket was beyond my budget. Later, on the Matterhorn again during the opening of a new route, I relied on a cycling jacket instead of a warm fleece.

I remember those years vividly because they taught me something that still shapes my approach today: learning to live with the elements, even in the harshest conditions, without complaining and without expecting nature to adapt to me.

The first real breakthrough, when it comes to shells, was something I felt directly on my skin the day I wore a jacket that could truly breathe during prolonged effort.

It was not a sudden revelation. It came through years of testing and collaboration with brands in my role as both an athlete and a product development partner, a role I still carry out with great enthusiasm today. Thinner membranes, smarter seam construction, and cuts designed to move with the body rather than simply keep the elements at bay: these were innovations I had the opportunity to put to the test during demanding expeditions, difficult ascents, and countless training days throughout the Alps.

Over time, I realized that my role in product development is not simply to wear a garment and say whether it works. My job is to take it where it will be asked to perform for real. It means placing a product in situations where every detail matters: when your hands are cold, your pack is heavy, the wind is building, snow is finding its way everywhere, and you still need to keep moving.

That is where an idea conceived behind a computer screen meets reality.

In some way, I serve as the link between these two worlds. On one side are designers, technicians, pattern makers, and developers studying materials, construction techniques, and technical solutions. On the other is the mountain, which offers no shortcuts and accepts no compromises. My role is to bring back what I have learned in the field and transform it, together with those who create the products, into meaningful improvements.

Sometimes that means something very small: moving a pocket a few centimeters, changing a zipper, adjusting the volume of a hood. Other times it means questioning an entire design solution.

It is a continuous dialogue between experience and technology. And I believe the best products are born precisely from this dialogue, not when technology tries to stay ahead of the mountain, but when it listens to what the mountain has to teach.

This has certainly been true in recent years with the development of the new Vertigo line and the work carried out together with the Montura product development team. Long days spent refining every detail in the design studio were followed by weeks of field testing to determine whether what looked right on paper truly worked in the mountains.

Because that is where a product reveals its truth.

Especially during bad weather, in the harshest conditions, and on expeditions. That is where you discover whether a cut is genuinely functional, whether a closure can be operated with numb fingers, and whether a membrane can effectively manage heat when the body is working at its limit.

A perfect example is the new down jackets I tested on Numbur last October during their final field evaluation: an unplanned bivouac at 6,900 meters, with temperatures dropping well below -25°C.

Fortunately, I returned to the valley with the certainty that what we had imagined, studied, and developed had achieved its purpose: offering comfort in demanding environments and, above all, allowing me to focus on what truly mattered at that moment.

“There are the details that seem minor on paper but can make an enormous difference in the field.”

Waterproofness is a word found on almost every label, but at altitude it only tells part of the story.

A shell can be waterproof on paper and still turn into a steam chamber the moment you start climbing a couloir with a heavy backpack. The real question is not simply, “Will it keep water out?” For a garment of this level, that should almost be a given.

The more important questions are: Can it effectively dissipate the heat and moisture I produce? Is it durable enough when rubbing against rock on mixed terrain? Will it stand up to the storm when it arrives? If an ice axe or crampon accidentally punctures it, how will the fabric react? And perhaps most importantly: Can it be repaired?

Then there are the details that seem minor on paper but can make an enormous difference in the field.

A front zipper that can be operated without removing gloves. A hood that follows the movement of your head, even when worn over a helmet, without restricting your field of vision when looking up to read the route. Cuffs that keep snow out while remaining compatible with different types of gloves.

These details may appear small, but together they define our relationship with a jacket.

Because when a technical garment truly works, it slowly becomes more than just a piece of equipment. It becomes something familiar, something we trust, and something we choose again and again.

And when, years later, we are finally forced to replace it with a more advanced model, that old jacket will not simply be a worn-out garment hanging in a closet. It will carry with it memories of mountains, challenges, emotions, and adventures experienced together.

Materials have evolved enormously.

Today we have lighter membranes offering the same level of weather resistance, insulation that continues to perform even in damp conditions, and fabrics that move naturally with the body instead of restricting it. In the mountains, this is not simply about comfort or performance. It is also about safety.

A garment that keeps cold and moisture at bay allows you to preserve energy and mental clarity for longer. And clarity, whether you are at high altitude, exposed to extreme cold, or climbing a technical face, can make all the difference when important decisions need to be made.

But there is one limit that no membrane will ever overcome: technology cannot make decisions for you.

It can reduce the number of variables you need to manage. It can shield you better. It can help preserve your energy. But it cannot replace your ability to read the terrain, the sky, the snow, or the wind. Most importantly, it cannot replace your judgment when it is time to turn back.

A more advanced shell does not make me stronger, nor does it teach me how to read a mountain face. It simply removes some of the obstacles that, in the past, would have consumed valuable energy and attention.

The mountains, on the other hand, have not changed their rules. They still demand humility, adaptability, and the willingness to retreat when necessary.

Perhaps that is where innovation and experience truly meet: materials evolve, while the mountain remains the same demanding teacher it has always been.

For those of us involved in product development, the responsibility is not simply to create something lighter, stronger, or more technically advanced. It is to understand what we genuinely need when conditions become difficult and to have the courage to communicate that reality to those designing the product.

Because technology only has value when it answers a real need.

My role, then, is to bring the voice of the mountain into the design process. To bring it back to the company, discuss it with the people who design, cut, sew, and develop materials, and then return to the field to discover whether we have taken a step in the right direction.

The mountains will never change their rules for us.

What we can do is learn to listen more carefully.

And perhaps that, in the end, is the most authentic meaning of innovation: not making the mountain easier, but enabling people to face it with greater awareness.