'Softer, lighter version of Gore-Tex fabric cuts weight and bulk of the beautifully-made Helio Shell, but it's quite a specialist lightweight alpine-orientated beast.'
Outdoors Magic: Beautifully put together, softer feel Gore-Tex C-Knit fabric, light and packable, easy to use Cohaesive cord-grips, decently breathable.
Outdoors Tragic: Cut is quite high volume for a lightweight, hood peak has minimal stiffening. Durability?
Outdoors Grabbit? It's Gore-Tex Jim, but not as we know it. The Helio is light, breathable, feels nice and is beautifully constructed. The C-Knit fabric lacks Gore-Tex Pro's toughness though, so we'd say it's quite a specialist shell that works best with a helmet thanks to the lack of peak stiffness. It also has quite a high volume and longer than average cut which won't suit everyone.
Lightweight alpine and ski-mountaineering jacket / GORE-TEX with C-Knit backer technology / Cohaesive™ cord management system / full-length pit-zips / custom-moulded cuff tabs / two Napoleon-style cross-access chest pockets / helmet-compatible hood with laminated brim / adjustable hem, cuffs and hood / soft-lined collar.
Full Review Below
Black Diamond Helio Shell - The Tech
Gore-Tex is quite strict about which of their family of fabrics is best used for what. The norm for mountaineering jackets is Gore-Tex Pro, but BD has bucked the trend by choosing the Gore-Tex with C-Knit backer material to save weight and bulk. As a bonus, it also has a softer, quieter feel than the crackly Pro.
'The other stand-out feature of the Helio Shell is the use of South African Cohaesive cord-locks. They're button-shaped, super tough and very easy to use with gloved hands.'
How much weight does it save? It's hard to say exactly, but a same size Arc'teryx Beta LT made from Gore-Tex Pro is actually 10g lighter on the same balance and probably outright tougher and more durable.
That said, the C-Knit backer fabric feels a lot softer and notably quieter, breathes pretty well and, used as intended, should be tough enough. It's normally used for less-technical walking jackets though.
To put in in perspective, the previous lightweight BD MonoPoint Shell weighed 100g less and used Gore-Tex Paclite, a fabric we wouldn't choose for high mountain use, so the switch makes sense from that point of view.
The other stand-out feature of the Helio Shell is the use of Canadian Cohaesive cord-locks. They're button-shaped, super tough and very easy to use with gloved hands. They're also being rolled out by Berghaus for its Extrem 8000 Pro jacket and, believe it or not, Alpkit in its latest full mountain shell. And yes, that is how you spell the name.
Black Diamond Helio Shell - Performance
It's a beautiful thing the BD Helio. Really nicely put together with impeccable laminating, welding and taping. Just a nicely-made object. It's decently light too at a real world 360g for a medium, making ideal for stashing in your pack until needed.
The Gore-Tex C-Knit fabric gives it a nice feel. It's softer and quieter than Pro, which will either bother you or not. We liked it, but we suspect that it won't be quite as durable when faced with sustained mountain abuse.
Cut Of The Jib...
We were a little surprised by the cut of the jacket. It's longer than average and there's quite a lot of internal space thanks to a slightly barrel-ish fit. On the plus side it broadens its appeal beyond those built like pedigree mountain cheetahs and/or allows layering over bulkier insulation layers if necessary.
'Need more cooling? The cuffs allow you to roll up your sleeves easily too. And did we mention those Cohaesive cord-locks, erm, oh, we did.'
Also unusual is the single-pull hood adjuster out back. It runs through one of those glove-friendly Cohaesive cord-locks - there's another on the hem - and tightens both top and front cords with a single pull.
What's more it works pretty well both with and without a helmet in situ and we felt nicely sealed up. If we're being critical, we'd have preferred a stiffer and/or wired peak for UK conditions, but to be fair, used as intended for lightweight alpine stuff or ski-mountaineering, chances are you'd be wearing a helmet. It does limit its usability for more general stuff though.
Everything else works well. The great big Napoleon-style chest pockets are perfectly placed to use with a pack or harness. The moulded zip-pulls are easy to grab with gloves. And the big pit-zips, give plenty of cooling, though you'll only leave both zip-pulls at the back end once when out with a pack.
Need more cooling? The cuffs allow you to roll up your sleeves easily too. And did we mention those Cohaesive cord-locks, erm, oh, we did.
Black Diamond Helio Shell - Verdict
The Helio Shell's beautifully made and the Gore-Tex with C-Knit fabric gives it a nicer feel than crispier-sounding Pro alternatives, but it's also quite a specialised beast that's at its best with fast and light alpine missions.
In those conditions the softish hood peak and slightly less durable fabric aren't serious issues. For more general mountain use though, certainly for all-day UK winter mountaineering, we'd be looking at something a little more rugged and with a stiffer peak.