Webstore Manager Steve has been putting the all-new Rab Firewall Mountain to the test, stepping into it after retiring his much-loved Mountain Equipment Rupal – which served him well for over six years.
After more than six years of solid service from my Mountain Equipment Rupal, it was time to look for a new waterproof. The Rupal has been brilliant – tough, dependable, and protective – but as it’s aged, the breathability has dropped off a bit and the fabric’s starting to show signs of wear. I was after something equally reliable but a touch lighter and more breathable for fast-moving days on the hill.
After some research and trying a few options, I landed on the RAB Firewall Mountain Jacket – and so far, I’m very impressed.
Key Features and First Impressions
The Firewall is built from Pertex Shield 3-layer fabric, offering waterproof protection with a softer, more flexible feel than traditional GORE-TEX. It immediately felt lighter and more pliable than my Rupal – definitely easier to pack and more comfortable for dynamic movement like scrambling or steep ascents.
Notable features include:
• Helmet-compatible hood with a wired, laminated peak – excellent adjustment, and it stays put in heavy wind.
• Long YKK pit zips with dual sliders – these run right down the torso, offering exceptional ventilation.
• Two large hand pockets and a Napoleon chest pocket – all water-resistant and well placed.
• Velcro cuffs and adjustable hem drawcord to seal out the elements.
• Softer inner lining that feels comfortable against the skin even with a short-sleeved base layer.
Weather Performance
I’ve tested the jacket in some proper Scottish Island downpours and a blustery hike across the South West Coast Path, and I’ve been pleasantly surprised. While it’s not as heavy-duty as GORE-TEX Pro in terms of outright storm shielding, the Pertex Shield fabric has kept me bone dry so far – and it breathes noticeably better on warmer, wetter days.
The long pit zips are a standout – I ran them wide open during a hot uphill slog and stayed cool without needing to take the jacket off. That’s something my old Rupal simply couldn’t match.
Windproofing is excellent, too. On a windswept ridgeline, the jacket didn’t flap or ride up, and I never felt exposed.
Fit and Feel
Fit-wise, I went for Large, and it’s spot on. There’s room for a fleece or light insulated layer underneath, but it still feels trim and athletic. The cut is a bit longer in the back, which is great for keeping covered when moving, and the jacket moves well with the body.
Compared to the Rupal, it’s noticeably lighter, more flexible, and easier to stash in a rucksack – ideal for changeable days or fast-and-light missions.
Final Thoughts
If you’ve loved a solid mountain shell like the Mountain Equipment Rupal but want something lighter, more breathable, and just as capable in poor weather, the RAB Firewall Mountain Jacket is a fantastic option.
It may not have the absolute bombproof feel of a GORE-TEX Pro shell, but in real-world conditions – especially when you’re on the move – it strikes a brilliant balance between protection and comfort for those unexpected summer mountain downpours.
A great all-rounder for UK hills and mountains, especially if you’re walking, scrambling, or hiking in mixed weather or warm climates
