State of the art high mountain boots
08 November 2008
Note: Many of these articles are very old, and although the technical information is still relevant the equipment mentioned may not be (for example a Stormy cooker was state of that art in 1995, but not in 2021).
Not that long ago going on an expedition was a really big deal. Being part of the expedition meant being part of a big team of mountaineers who were throwing themselves at a major objective far from home, it was what all climbers wanted to do, it was a once in a lifetime opportunity, it was living the dream.
In those days mountains like Cho Oyu, Denali or Ama Dablam required major expedition logistics, with a year of planning and organization before you went. One of the biggest tasks was accumulating all the specialist equipment needed for the big mountains. If the team was to have a chance at high altitude they would have to search out and procure hard-to-find exotic gear, gear like down clothing, expedition weight season sleeping bags and specialist boots. Getting this gear together could take months of hard work and networking.
The priority when collecting together expedition gear was -and still is- footwear. High altitude ‘Alveolite’ inner boots would need to be tracked down from somewhere and then fitted to old shells and neoprene overboots ordered so they could be made up in time.
Those expedition members who failed to appreciate the importance of warm boots and made do with their standard low-level footwear were often forced to turn around close to the summits they had travelled so far - and expensively - to reach and there were always the others, those who chose to carry on, feeling their toes - or worse - worth the sacrifice. How times have changed. Old school expeditions are a thing of a past, or at least the way they were once viewed, save only by those keen to hark back to their imperial traditions when venturing into the old Empire, or as a word used as leverage, bandied around in the presence of potential sponsors.
The expedition has been replaced by the ‘trip’ a word that does better justice to the more informal, smaller teams now heading off to attempt routes in the high mountains. With very little fuss or fanfare these groups are attempting the big objectives once tackled by big teams, tackling routes in a more informal way, sometimes Alpine style, other times using more traditional methods but applying the lighter touch of that style - all to good effect.
Commercial trips are also now commonplace, removing much of the pretension from the Expedition, with many climbers who would never have been included, or have wanted to be, now buying into good value commercial trips to several high mountain destinations.
This commercialism has helped in many ways to demystify the high mountains and open up the closed world of the high mountains to the climbing masses - even dumb it down - as people see that anything is possible, as they watch live webcasts from Everest of dentists from Denver battling for space among snowboarders, paragliders and Sherpas running laps. The supply of specialist high altitude and extreme equipment has had to grow as expeditioning has gone mass market. This has led to the once-unimaginable situation where shops are holding stock of expedition equipment so that climbers can turn up the day before a trip to deck themselves out (unbelievable but true). The footwear manufacturers have also kept pace, firstly by making high altitude versions of their standard boots more readily available (Asolo Expedition, Vega High Altitude, Koflach Arctic Extreme) in shops and now introducing dedicated high altitude models to feed this market.
This article is designed for the British climber who wants the best expedition footwear for their ‘trip’ or ‘holiday’, whether it’s a trip up a 6,000m peak, an Antarctic giant or for a shot at an 8,000m scrum. I’ve also included the best ways to keep those toes, whether you have fancy boots or not.
Not long ago there were simply ‘plastics’, now we have competition boots with no sole and bolted on sport crampons, double leathers that look like plastics, expedition boots that look like something out of Judge Dredd and even plastics with no plastic in them. In order to get an idea of where the different boots fit I’ve broken them down into four broad groups.
(Scarpa Cumbre, Sportiva Nepal Extreme, Salomon Pro Ice, Boreal Super Latok etc)
Designed for maximum climbing performance, leathers sacrifice upper insulation in order to save weight and bulk and underfoot insulation is also reduced in order to keep the foot close to the crampon for more feel.
Well-fitting leather boots are adequate for short adventures into the cold, but not extended stays due to the fact they give low insulation even if insulated (Thinsulate is just that Ñ thin) and so it’s advisable that anyone wishing to use a pair in extremely cold conditions (early season ice in Canada or Norway for example), should make sure the boots are roomy and fitted with plenty of socks and a thick insole.
There are several double leather boots on the market that provide higher levels of insulation, but personally, I think these are the worse of both worlds, being clunky like a plastic boot yet they still freeze up. There are a number of boots on the market (Sportiva Trango Comp, Scarpa Freney-XT) that use synthetic fabrics that are not as affected by the cold, but at the end of the day you don’t want a pair of icy boots inside your sleeping bag no matter what they’re made of and so although Boukreev soloed Broad Peak in a pair and I met a Canadian who wore his Nepal Extremes for a month on the Patagonian icecap in winter (temps of -30¡), they are best kept for pure athletic, single-day winter climbs, or for dry/warm Alpine routes.
(Scarpa Vega and Alpha, Asolo SuperSoft/101, Lowa Civetta etc)
These boots span the gap between light leathers and clunky state-of-the-art expedition boots and so have a share of each boot’s pros and cons. They are suitable for extended cold use as they can be split so that the inner boot can be kept warm in the sleeping bag and can provide enough insulation if used correctly at any altitude as long as the temperature doesn’t drop too far.
The inner boots are designed to provide warmth with a bias towards a good climbing fit, using robust, compressible, open-cell foam over more expensive, thick and insensitive closed-cell foam. This foam keeps your feet a little drier as the foam will absorb sweat and also makes the boots feel closer fitting.
These boots were the old expedition standard and for cold routes or high altitude ventures, they are often matched up with a pair of insulated overboots in order to boost the boot’s performance (especially underfoot). Another option is to upgrade the boot by fitting closed cell inners. These used to come from the boot manufacturers (about half the cost of the whole boot), but many climbers are now buying closed-cell thermofitted inners from ski shops (around £100), which are also made from closed cell foam and have the advantage that the fitter can tweak the shape to suit your feet.
(Scarpa High Altitude Vega, Koflach Artic Extreme)
These boots are standard plastic shells fitted with closed-cell inner boots. Closed-cell inner boots will not absorb as much moisture and so provide a more constant insulation level over a longer period, crucial if you’re unable to dry your inner boots out after a week-long slog up to your high camp. These inner boots were commonly called Alveolite in the past, but this is just a brand name for a closed-cell foam (like Karrimat) and simply translates as foam with small holes in it (Latin don’t you know). The inner boots are also designed to be more idiot-proof than a standard inner in order to make them easier to put on when your brain is wasted, reducing the lacing or replacing it with Velcro, resulting in a less technical but easier to use and warmer fit (no lacing over the foot). If you’re heading off to try a technical route in the cold then these are the boots to choose from, as they provide a good balance between performance and warmth.
Many climbers heading off to cold mountains like Denali also buy (or rent) overboots to boost the boot’s warmth, which is a compromise between buying a warmer, dedicated pair of boots. One reason for this is that climbers want to use their boots for high altitude, Alpine and Scottish climbing. In reality, it’s hard to cover all these bases with one shell, leaving you with a boot that’s too big to climb well in or too tight for cold use. At the moment I’m using a pair of oversized Scarpa Alphas fitted with Vega high altitude inners, which gives me a warm boot that is as light and nimble as most leathers yet won’t freeze and these have been used in the Alps in both the winter and summer, along with Norway and Scotland. These boots are great for doing technical climbing in the cold as long as you take care of your socks, but they begin to lose it if I’m forced to stand around too long as the slim shell isn’t roomy enough and if the temperature really drops I know I’m going to suffer.
(Millet Everest, La Sportiva Olympus Mons etc).
These boots are the current state-of-the-art in extreme cold footwear. Their extra warmth comes from use of the best thermal materials available and, largely, ignoring the cost; materials like PE foams, honeycombed plastics, reflective barriers and carbon fibre, with this insulation being applied to both the construction of the inner and the shell. This gives the shell alone as much warmth as any extreme plastic, doubling the boot’s warmth once the inner is added. These boots are designed from scratch for expedition use, not upgraded from ice-climbing boots and are designed to be idiot-proof, robust and suitable for easy to moderate terrain (high altitude trekking rather than pure climbing). Below is a roundup of the three main boots on the market.
Price: £395 Size range: 6-13 (including half sizes) Weight: 2,800 grams
This was the first of the dedicated high altitude boots and very quickly became the boot for anyone going high in the Himalayas. The original blurb was that these boots were guaranteed down to -40¡ and I was told that Beck Weathers was wearing a pair which explains why he kept his toes even though he lost his fingers and nose when left for dead on Everest. Very quickly these boots also became popular for other areas and for trips to the Arctic, being especially popular among North American climbers on Denali. Although very exotic the number of boots sold in the UK when they first appeared pointed to the increased interest in specialist high altitude gear and I can remember working at Outside and selling more Everests than Vegas.
The Everest was one of the first boots to be designed with warmth taking priority over climbing performance and even though other boots have come along since then they are probably still the hottest climbing boot on the market. It features an integrated insulated gaiter, which saves a great deal of hassle and boosts warmth. This gaiter allows the user to use the boots without the inner (you can just slip your feet in with your socks or down boots on), useful if you need to go and dig out the tent in the middle of the night. The shell of the boot is not plastic, but made from layers of closed-cell foam, reflective fabric and Cordura, all of which are designed to provide more warmth than denser plastic, with this outer shell alone being as warm as any Super Alpine inner boot. The midsole is made from thick layers of foam and carbon fibre, massively decreasing underfoot conduction compared to a hard plastic sole. The shell is cinched down with several Velcro straps, which is a real boon compared to frozen laces, the bane of all winter climbers. They also make it easy to take on and off, tighten or slacken, with mitts on. The inner boot is made from reflective material covered with closed-cell foam and feature a foam insole.
As I said, the Everest is not designed for technical climbing (although Tomaz Humar wears them), as the last is very generous and the boots themselves are incredibly bulbous. Steep ground is probably best tackled with a bit of French style footwork if possible, sidestepping rather than front pointing.
Many climbers use step-in bindings with the Everest, but personally, I recommend either a hybrid binding (G12, S12, DMM Aiguille etc) or, better still, a modern strap-on model like the BD Contact Strap or G12 New Classic (you’ll probably need longer straps to be fitted). The reason is that the lip of the sole is very soft and can deform far more easily than a more solid climbing sole, which could easily result in the front bail popping not a great idea if you’re exhaustedly descending down the Lhotse Face.
Sizing has always been very weird with these boots and I would not recommend buying any without trying them on first. Due to their relaxed last, I personally think these are best suited to slow high altitude plodding than anything more serious and I would also recommend the boots to be broken in before heading to the big mountains, as the foam compresses with use, allowing you to get a better idea how many socks, or what insole to wear, once broken in (just think how great you’ll look on the top of Snowdon).
At the end of the day take off your shells and knock or wipe out any snow or ice inside. Don’t leave the shell outside in the snow, put them under your head and use them as a pillow, or stow them inside your rucksack. This is done to try and stop them from getting supercooled, resulting in them supercooling your inner the following morning. If the laces are icy then try removing them with your teeth (WD-40 can work well on laces).
Next, get into your sleeping bag with your inners on after first loosening the laces. You should have a plastic zip-lock bag with a complete spare pair of socks ready. Take these out and put them next to your skin to warm up. Next, remove one of your inners and take off your socks, sticking them down your top for later. Once your feet are bare, dry them off with something and then rub them to get rid of any clamminess and promote circulation. Once this is done put on your dry socks. Your feet should now be warm. Repeat with the other foot. If you’re into a bit of luxury you may have some down booties as well.
Don’t just stick them on. Try to warm them up first, I do this by blowing my hot breath into the boot then pulling it on. Remember to pull your socks up and try to avoid any gaps in your legwear at the ankle. Next, dry out the inside of the inner boot using one of the removed socks. This is often best done by first removing the insole. Once dry (closed-cell foam will just have moisture on the surface) the inners can either be put back on loosely laced, half put on (toes in the heel), or placed somewhere inside the bag to stay warm. Personally, I put them at the foot end to give my feet a little more underfoot insulation from the ground. Fill your water bottle for the night and the next morning with hot water and place it between your thighs (not at your feet), as this will warm the blood heading down to your feet.
Before you go to sleep take your damp socks and lay them flat next to your skin (grim but worth it). I usually lay the socks across my stomach, chest or thighs. Another option is to wear them on your hands and stick your hands next to your skin or in your pockets. In the morning these socks should be dry and they are put in the zip lock bag and put away for the coming night. Your inner boots and socks should all be warm and ready for action now and all you need to do is tighten up your shells. If using the stove it might be worth holding both the inner and outer over the flame (don’t set fire to your boots for God’s sake), in order to remove any chill and start the day off with hot boots.
The majority of frostbite cases could have been prevented if climbers had followed these basic rules. Starting off with wet socks, inner boots that have been left to freeze, or shells encased with ice is like begging for black toes.
Price: £425 Size range: 39-47 (full sizes) Weight: 2,900 grams
The Olympus Mons is probably best described as a Millet Everest designed for technical climbing. The whole boot is much more finely tuned and obviously designed to provide a better, more technical fit by sacrificing some of the boot’s bulk (warmth). The boot is still incredibly warm and having used a pair on two of the coldest climbs I’ve done I’d have no hesitation recommending them to anyone heading high and cold.
The first thing you notice when using these boots is that whoever designed them really knew what it was like to use boots like these in the mountains. Every little detail, from the bulletproof gaiter to the pull tab you can get your hand through (not just your little finger), shows that these boots were expedition proven before they went into production (other manufacturers take note). The thing I like best is the way the inner boots slip into the outers like a dream, a crucial piece of engineering when trying to don shells on a cramped bivvy and a source of envy when your partner spends five minutes stamping his feet into his 101s. Like the Everest, the Olympus Mons’s outer boot is a laminate of Cordura, dual-density PE micro-cellular thermal insulating closed cell foam (try saying that when drunk), which is backed with a thermo-reflective aluminium facing. The inner is lined with plastic so that no moisture can get into the shell and cause it to freeze.
One downside is that the shell uses laces, which although fine when dry, become hard to use and tighten when frozen. This can result in a poor fit for climbing, in that although tight when you first put them on, the laces become slack as they thaw causing the whole boot to become sloppy. Personally, I’d prefer to see Velcro used on the shell.
The inner boot uses perforated closed PE cell foam with a wicking polyester lining and laces from the top to near the toe and is obviously designed to give a close, low bulk, technical fit. One bonus of the design is that it’s not too bad to sleep in the inners (always a no-no), as moisture can escape out through the holes in the foam and the polyester helps the inner dry on the feet. The midsole is made up of a 6mm insulating honeycomb structure of carbon fibre with a PU insert and the sole unit provides good grip on rock and takes most crampons well.
Although I suffer from poor circulation in my feet, these boots kept them toasty on the Dru, even when forced to endure hours of sub-zero belay duty. I also used the boots on Mermoz and although I wouldn’t kid you that they were awesome technical boots I did lead several hard Scottish VI pitches with no problem, only finding them scary when front pointing (ice ranging between 45¡ and 90¡). This was probably due both to the nature of the boot (i.e a LOT of foam that can compress) and the problem with the laces (a power strap could help) and although you could just stop and crank them up, this isn’t always possible.
Price: £280 Size range: 36-48 (including half sizes) Weight: 2,150 grams
The 9000 is another step nearer to the high altitude boot you can climb in and so is perhaps another step away from the warmth of the Olympus Mons. The boot looks more traditional, coming without an integral gaiter, but this hides the complex state of the art construction, with the shell being constructed from thermoplastic urethane, Kevlar mesh, Mylar film and Aveo foam. The result is a construction that is light, flexes like leather and is far warmer than a Super Alpine plastic. The inner is made from a combination of open and closed-cell foam. The shell features a 5.10 stealth sole and rand and the whole lasting and design shows that the boot was intended for cold climbs, with the complete package being surprisingly lightweight and nibble. Front pointing-wise the combination of a plastic shell and thinner materials make the boot a good front point performer, especially when you consider how warm they are. The boots have been designed and tested by the legendary US climber Jack Tackle, and it shows, although there are still a few niggling problems (like a pull tab so small you need to clip a krab in it in order to use it). I’ve climbed with two climbers wearing these boots in the last six months and both were very positive about the fit and the warmth (neither got cold feet even though it was Baltic).
Technical development in mountaineering boots has been slow over the last two decades but it looks like things are speeding up. In June, Scarpa brings out their Phantom 8000 (£500/2,950 grams), which is set to push the design envelope even further. Boreal also have a new boot in the shape of the G1 Expe (2,770 grams), which combines several of the materials above in a double gaitered boot including leather. Those climbers who venture into the most extreme altitudes and conditions are walking a fine line between survival and death and so are willing to pay a premium for the best protection. This willingness to pay will spur the boot companies to make further developments which should trickle down to the lower level plastics and leathers so that even if you’re not attempting Mount Vinson you can still expect hot feet.
A few questions. How expensive is your trip? How much money will you lose if you’re turned around 100m from the top because your feet feel like wood? How much are your toes worth to you? If you break down your £400 boots between all 10 toes then that’s only £40 a toe. Is that too much to ask? Are you going to do more than one trip up high? Are you keen on doing the seven summits perhaps? If so then that £40 could fall to a couple of quid a toe.
Having used these boots I’d say that the investment is worth it, both for the safety factor and the comfort and confidence these kinds of boots bring. Put it this way, I’ve seen a lot of climbers who whine about the price of good boots, who then fork out £300 on a new Gore-Tex for their holiday, when a cheap £50 Regatta shell would do. Remember, you can’t put your feet in your pocketÉ well not until after the operation to remove them. VAPOUR BARRIER SOCKS
The vapour barrier sock (or VBL sock) has been an integral part of high altitude foot care for the last couple of decades. The sock is made from an unbreathable watertight material and is worn over a thin liner sock and is designed to stop the thicker insulating sock(s) or inner boot from becoming thermally compromised by sweat (especially if the inner boot is made with open-cell foam).
At the end of the day, the VBL and liner socks are removed and dried and a fresh pair of liners put on along with the thicker socks. The use of a VBL sock also increases warmth due to the fact that less energy is lost through sweating, as the foot should stop sweating when the humidity level within the sock reaches 100%.
Drawbacks with the system are, firstly, the socks are very slick, causing the foot to swish around within the sock sandwich, meaning you need to crank up the boots for climbing which sort of makes the use of the sock in the first place a bit of a non-starter. Secondly, your feet can rot and I mean quickly. The US army says that trench foot can begin within 14 hours of immersion, which means you need to really look after your feet if using these things day after day. If you’re a sufferer of athletes’ foot then VBL socks could really accelerate any infection, potentially halting your climb. For long term trips, I recommend taking plenty of spare liners (they get saturated in ammonia), talc and make sure you clean your feet with snow every night. Sleeping in VBLs is not recommended. One way to limit some of the problems is to rub antiperspirant gel into the feet each morning to limit sweating, which can also work well for non VBL sock users.
So do they work? Personally, I hate the loss of control of the foot due to the slick layers and find my feet don’t stop sweating, leaving my feet looking like Uncle Ben’s boil in the bag feet. Saying that, I’ve never worn them for slower aerobic, high-altitude routes, where foot perspiration may not be high, so for routes like Denali, or for use on trekking peaks with leather boots, they may perform better. I think the technique was more important in the past where climbers were using double leather boots, or first-generation plastics with Loden inner boots and so with better socks and vapour impermeable inners their use is not so critical.
At the moment I think PHD is the only company that are manufacturing VBL socks and at only £18 a pair (60 grams) they’re not so expensive or heavy to try out yourself, or you can just use bread bags.
These are giant insulated boots that are used over your existing boot in order to boost their warmth. An overboot encases the whole boot in foam, either Neoprene, closed or open cell and is infinitely warmer than a Yeti gaiter as it adds warmth both to the upper and the more vulnerable sole of the boot.
Overboots are relatively cheap (£100) and can be added and removed easily in the field and are also lightweight and pretty robust. Their drawbacks are that they can only be worn with crampons and crampon fitting can be a hassle unless you use a modern full strap model. For climbers with boots they suspect won’t keep them warm (they can be worn with leathers) they are a good option, but otherwise, it’s best to put the cash towards a proper pair of expedition boots. Mountain Hardwear and Berghaus are the only people supplying overboots in the UK, with other US companies like Outdoor Research and Forty Below only selling via mail order.