Berghaus’s Thindown insulation promises hot performance benefits, but does it make the Aonach hot property for hillwalkers?
Material Insulation Thindown (750 fill power down/synthetic mix), shell 88% polyester, 12% elastane
Weight 557g (size L)
Staying warm in winter is easy in principle. You just add loads of extra layers of clothing that trap extra pockets of warm air against the body, right? Wrong! If you just add more layers you end up with a bulk of clothing that limits easy movement and reduces breathability. Then there is the weight of all those layers and also their financial cost. Instead what is needed is just one layer that offers the right amount of insulation in the lightest form, with the most practical design and at the lowest price possible. Great in principle.
Enter Thindown, the new form of insulation from Berghaus that is used in the Aonach jacket. During manufacturing down is fused with polyester to create an interlocked stable sheet of Thindown insulation. This insulation is said to be 30% warmer than polyester insulation alone, as well as being more compressible and more durable, while also retaining its loft and warmth much longer than standard polyester.
As Thindown is a stable sheet of material it is much easier to hold in place within a jacket, so there is less need for the complex array of stitched baffles used on conventional down jackets. Also there’s no need to use fabrics that are designed to prevent pieces of down escaping, such as tightly woven nylons, leaving the way clear for more open-weave materials that allow for far greater levels of airflow and breathability. Berghaus claims the shell material on the Aonach is 50 times more breathable than a standard down jacket, and describes the Aonach as ‘the world’s first truly breathable down garment’.
As the Aonach is so breathable, Berghaus also claims it can be worn under a waterproof hardshell jacket without any build-up of condensation. It’s also warmer than a fleece, while stretch fabrics have been used to enhance the fit and freedom of movement. If that wasn’t enough the Aonach also uses 50% recycled materials and over 90% of the materials are Bluesign approved for their environmental performance.
I took the Aonach on the hill at the start of autumn, and wore it under a waterproof jacket to block out the wind while heading up steep slopes on the Lakeland fells. It was immediately apparent the condensation you’d normally expect when wearing a synthetic or down insulation jacket under a waterproof did not materialise. The tricky part of the equation though, is the Aonach is pretty warm. It feels like you are wearing a thick fleece, or even two thin fleeces, so I found the Aonach just too hot for a lot of hillwalks. If you use the Aonach as an extra layer to throw on when you stop walking then its breathability benefit is less useful, as you won’t get condensation when resting anyway. So this means the Aonach is going to be best for really cold weather when you are still moving, making it more of a go-to jacket for those really cold winter days when you want something extra to throw on while walking, such as a second fleece or thin synthetic jacket or gilet.
The Aonach weighs 557g (size L), so is a similar weight to a good general fleece jacket. There are pure down jackets that are lighter though. For a jacket designed to keep you warm when being active, it is surprising there is no hem drawcord, no hood drawcords and no cuff Velcro tabs to lock out draughts, and I definitely needed a closer fit at the hem. Also, if this is designed to be worn while walking then it needs a layout of pockets that allow easier access while wearing rucksack belts, and other jackets are better in this area.
Finally the thin stretchy polyester outer is not the most durable, so if wearing this for rougher movement over rock then care is needed to prevent it snagging. I noticed the cuff area is a little baggy and already starting to show signs of abrasion from the rocks I had scrambled over.
The Aonach costs £200 but you could buy a good fleece jacket for £100, or a thin synthetic insulated jacket or warm down jacket for £150. A really light and warm down jacket, meanwhile, would set you back around £270. So you need to be keen on the Aonach’s warmth, weight and breathability ratio to warrant the price tag then.
So is the Aonach right for your needs? For me, its ideal for those really cold hillwalks when a waterproof jacket, fleece jacket and base layer just aren’t enough, which means Scotland in winter and occasional days in England and Wales when the temperature plummets. But I’d like some design tweaks to make it perfect for use while walking uphill, rather than for just sitting on the summit and enjoying the view.
Berghaus’s Thindown is a great new material for backpackers, hillwalkers and mountaineers who need more breathable insulation when moving through freezing conditions, but for active use some design details could be better in the Aonach jacket.
In use 4/5
Value for money 3/5
OVERALL SCORE 88%
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The Helly Hansen Icefall uses 700 fill down, with water-resistant synthetic Primaloft Silver insulation on the shoulders. The outer is a soft Pertex that is not too rustly. The hood gets volume adjustment at the back plus face drawcords, and the cuffs have Velcro tab adjustment. It’s slightly heavier than some at 619g, and others have hydrophobic down or more water-resistant outers; but this still offers good features. 3/5
This jacket comes in a huge range of sizes: men’s XS-XXXXL and women’s XS-XXXXL. The L fitted me very well. The hood drawcords enabled the hood to sit neatly and move well with my head. The cuffs tended to ride up a little, but this is a minor niggle. The body was a good length. Basically good for sitting and standing around in the cold. 4/5
The Helly Hansen Icefall feels very cosy as it is packed full of down, and the soft Pertex shell really hugs the body. You get some soft brushed polyester around the chin to soften this area too. The hood cords do not cut into the face. This is warmer than some lighter jackets too, making it better for colder conditions. The pockets also have a soft fleece lining. 5/5
The Helly Hansen Icefall is warm and practical in many ways, but it is slightly heavier and bulkier than some as it is lacks the higher fill power down. The synthetic insulation on the shoulders means this area stays warmer, as the insulation is less impacted by moisture or compression, but this makes it heavier and bulkier. The down and shell are less water-resistant too. 3/5
Well-priced in terms of how warm it is and its general features, but higher-priced jackets are lighter or have additional benefits. 4/5
The Helly Hansen Icefall is a very well-priced warm jacket for colder conditions, but it is slightly heavy and has less water resistance than some. 3.8/5
Review by Graham Thompson
First published in Trail magazine February 2017
Available from August 2016, the Windjammer is designed primarily for climbers and alpinists. It’s Montane’s first jacket to be made from Gore Windstopper fabric, so it is extremely wind-resistant and also repels water well. You get a hood plus four well-placed chest pockets with mesh linings. It feels more like a very good waterproof jacket made from non-waterproof material. 4/5
The men’s version comes in sizes S-XXL while the women’s in available sizes 8-16. The fit is quite close and I found the cuffs ride up a little on raising my arms, although this may be due to this being a size M (although other medium-sized jackets did not have this problem). The hood fit was outstanding, though, and it moved perfectly with my head. 4/5
The Gore Windstopper fabric is less stretchy than fleece or woven fabrics, so the Montane Windjammer feels more like a waterproof jacket than a fleece and it is not as soft against bare arms either. It blocks out more wind and rain than the fleecier designs but is less suitable to wear under a waterproof. It is great that the cuffs get Velcro adjustment to improve comfort. 4/5
The Montane Windjammer is designed primarily as a climbing and mountaineering jacket so I would have expected better sleeve movement. But the fabric is great for this purpose. The two Napoleon chest pockets are ideal for smaller guidebooks and GPS receivers, while thetwo large main two pockets can be accessed above hipbelts and harnesses. The hood is superb and is a real highlight of the jacket. 4/5
This has great features for the money compared to some, but hillwalkers may be able to get all they need for less cash elsewhere. 3/5
The Montane Windjammer offers top wind and water resistance, but walkers may prefer a softer, more breathable design. 3.8/5
Review by Graham Thompson
First published in Trail magazine September 2016